Lark

Ethanol and outboard carbs

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My Tohatsu sailmaster 6 is in need of yet another carb repair and my redneck outboard guy decided his side gig was more lucrative then boats.   

Two questions:

1.    Should I repair the carb vs carb replacement vs driving 1 - 1.5 hours there an back (4-6 hours total) to go to a real shop?   I'm a basic shade tree mechanic but haven't messed with small engines much nor carbs.   I could probably swap a carb out for the time spent driving and not worry about shop hours conflicting with my work schedule.    I'm tempted to buy a new carb, buy a rebuild kit to rejet the old one during the off season, buy the service manual and stop being reliant on others.   'Solution 1 maritime' is the price winner with all of the above, if anybody can vouch for them.  I can buy a carb from boats.net (I've used them before).   I assume I would need a gasket too?    For years I trailer launched a smaller boat with a reliable Evinrude 2 cycle that works decade after decade with only routine winterizing, so I never actually had to know anything about outboard motors.   Its too thirsty and too wimpy to be a good primary on the pocket cruiser, but ends up being used as an alternate power source at least once a year due to mechanicals on the new Tohatsu.

2.  I'm pretty much stuck with ethanol.    My local marina sells road gas.   I do buy ethanol free when I get to travel.   I did everything the prior mechanic suggested.  The tank has seafoam and stabil.   I disconnect the fuel line and run the carb dry every single day.  I made it two years since the last rebuild (Third failure on a 4 year old motor).   I tried to run clean gas with seafoam after it died in the face of an approaching storm last week.   It idles but is unreliable under load and dies quickly at throttle (main jet per google?).   Since I occasionally do some coastal hops I need range.   Upgrading to electric isn't a good choice.   Any ideas on prevention, or should I just keep a second carb as a spare, pack it on trips and plan on swapping it out every year or two at an inconvenient time?  

My goal is to get the motor back in operation as quickly as possible.   Cost is secondary. 

Thanks 

 

  

 

 

 

 

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4 minutes ago, Lark said:

My Tohatsu sailmaster 6 is in need of yet another carb repair and my redneck outboard guy decided his side gig was more lucrative then boats.   

Two questions:

1.    Should I repair the carb vs carb replacement vs driving 1 - 1.5 hours there an back (4-6 hours total) to go to a real shop?   I'm a basic shade tree mechanic but haven't messed with small engines much nor carbs.   I could probably swap a carb out for the time spent driving and not worry about shop hours conflicting with my work schedule.    I'm tempted to buy a new carb, buy a rebuild kit to rejet the old one during the off season, buy the service manual and stop being reliant on others.   'Solution 1 maritime' is the price winner with all of the above, if anybody can vouch for them.  I can buy a carb from boats.net (I've used them before).   I assume I would need a gasket too?    For years I trailer launched a smaller boat with a reliable Evinrude 2 cycle that works decade after decade with only routine winterizing, so I never actually had to know anything about outboard motors.

2.  I'm pretty much stuck with ethanol.    My local marina sells road gas.   I do buy ethanol free when I get to travel (trailer launchable pocket cruiser).   I did everything the prior mechanic suggested.  The tank has seafoam and stabil.   I disconnect the fuel line and run the carb dry every single day.  I made it two years since the last rebuild (Third failure on a 4 year old motor).   I tried to run clean gas with seafoam after it died in the face of an approaching storm last week.   It idles but is unreliable under load and dies quickly at throttle (main jet per google?).   Since I occasionally do some coastal hops I need range.   Upgrading to electric isn't a good choice.   Any ideas on prevention, or should I just keep a second carb as a spare, pack it on trips and plan on swapping it out every year or two at an inconvenient time?  

My goal is to get the motor back in operation as quickly as possible.   Cost is secondary. 

Thanks 

 

  

 

 

 

 

Lark

I used to sail on Lake Eire out of Port Clinton, near Marblehead. I also have a 6 HP Tohatsu (vintage 2007). Yeah, the low emission carb has many tiny orifices that love collecting crud. Mine has run crappily enough (always at the start of the season) that I have torn it apart and cleaned it a few times. I have never needed a rebuild kit, just a good blasting with carb cleaner and a blast of air from my air compressor. It's a simple carb and it's easy to get to all the little orifices. After you do it once or twice you can field strip that thing in the dark in a rice paddy.  My general thoughts:

1. [this is from a post I made about two weeks ago]: You got this.  Story time. Each year I trailer my 4ksb to the UP in Michigan and launch into Lake Huron, then sail to the North Channel in Canada (eh). It's a big deal because it's my only two or three weeks of sailing each year. Eight years ago I arrive and start the 6hp Tohatsu, which runs at idle but just bogs-down in gear. At this time I had not ripped into the top end of my Tohatsu, so I tried a few half-hearted attempts at shaking the gremlins loose, but nothing effective. I want the darn thing to run right and I don't want to burn vacation days turning wrenches in the parking lot, and I need to get my boat off the dock. So I pull the motor, load it into my truck, catch the ferry to the closest outboard repair-fish bait shop, and walk in. Mechanic tests the motor in the tank and concludes my carb is clogged. He then removes his Leatherman multi-tool from his belt and proceeds to remove, disassemble, clean, and fix my carb. Took him about 15 minutes in total. In my former life I worked as a mechanic, so I was a little horrified he was using a Leatherman for the entire job. I think you can do better with real tools, but you don't need many. So let this boring tale serve to inspire you to remove and disassemble your carb if necessary. It is really easy. I have since pulled and cleaned my carb at least 2x, because it is prone to getting gunk and crud in it. I like carb cleaner but I love using a small compressor to blow through all the orifices. Once you do it the first time it will be old hand. And those low emissions carbs are notorious for clogging and getting gunk in them and then running oddly. 

 2. At the start of the season I used to test my OB in my shop, on a stand with the lower unit in a bucket of water. I'd let the engine start, idle, and I'd play with the throttle. Does it rev? Pissing water? All must be good. NOPE. My experience (above) taught me it's better to test the engine in a bucket, but put it into gear and rev it. Difference between how a cruddy carb will rev in neutral versus in gear. And I have had the carb start and idle just fine, but bog under throttle (but not in gear). So, if there's a mode of failure in those carbs, you will eventually experience it. But they are simple to pull and clean. 

3. Some people here are big on using real gasoline. Not sure if you can buy it in Ohio, but in Texas and Idaho it's easy to find. I don't bother. I DO run a fuel filter on my Tohatsu. 

Snubs

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1 hour ago, Lark said:

My Tohatsu sailmaster 6 is in need of yet another carb repair and my redneck outboard guy decided his side gig was more lucrative then boats.   

Two questions:

1.    Should I repair the carb vs carb replacement vs driving 1 - 1.5 hours there an back (4-6 hours total) to go to a real shop?   I'm a basic shade tree mechanic but haven't messed with small engines much nor carbs.   I could probably swap a carb out for the time spent driving and not worry about shop hours conflicting with my work schedule.    I'm tempted to buy a new carb, buy a rebuild kit to rejet the old one during the off season, buy the service manual and stop being reliant on others.   'Solution 1 maritime' is the price winner with all of the above, if anybody can vouch for them.  I can buy a carb from boats.net (I've used them before).   I assume I would need a gasket too?    For years I trailer launched a smaller boat with a reliable Evinrude 2 cycle that works decade after decade with only routine winterizing, so I never actually had to know anything about outboard motors.   Its too thirsty and too wimpy to be a good primary on the pocket cruiser, but ends up being used as an alternate power source at least once a year due to mechanicals on the new Tohatsu.

If replacement carbs are available and cost effective then just replace it.  You will need a new gasket, probably, maybe not if the old carb has been removed recently.

I don't know much about the Nissan/Tohatsu carbs specifically but the newer ones are hard to work on.  It took me three tries to get the Yamaha 8 carb for my boat to work the way it should.  On the third try I removed all the little drive-in caps and ended up running a wire through a hidden little blocked passage that no amount of solvent and compressed air would free up.  Even the people who work on boat motors for a living don't bat 1.000 with carb work.

Then if you need a winter project you can fiddle around rebuilding the old carb.

 

Quote

2.  I'm pretty much stuck with ethanol.    My local marina sells road gas.   I do buy ethanol free when I get to travel.   I did everything the prior mechanic suggested.  The tank has seafoam and stabil.   I disconnect the fuel line and run the carb dry every single day.  I made it two years since the last rebuild (Third failure on a 4 year old motor).   I tried to run clean gas with seafoam after it died in the face of an approaching storm last week.   It idles but is unreliable under load and dies quickly at throttle (main jet per google?).   Since I occasionally do some coastal hops I need range.   Upgrading to electric isn't a good choice.   Any ideas on prevention, or should I just keep a second carb as a spare, pack it on trips and plan on swapping it out every year or two at an inconvenient time?  

My goal is to get the motor back in operation as quickly as possible.   Cost is secondary.

After years of dealing with small engines, plus discussing fuel with a chemical engineer who worked in the petroleum business, I offer you this advice, based on the practices I follow myself. 

  1. Heat, time, exposure to air, and contamination with particulates and water are the problems.
  2. Use sealed containers made of metal or nonpermeable plastic and keep them sealed.  I use safety cans.  In containers that are not sealed, the butane fraction evaporates, the fuel reacts with oxygen, and water condenses out of the air or is absorbed by ethanol-containing fuel (which is hygroscopic).
  3. Fuel deteriorates quickly over the summer if exposed to heat, and does not deteriorate to any material degree over the winter, at least in places where it snows, as long as it is in a sealed container.  In the summer, rotate fuel before it deteriorates, and safely dispose of questionable fuel.  Keep fuel as cool as possible, by keeping it in the shade.  In hot weather, do not load more fuel than you can use in a few months.  Fuel kept in a sealed container at 50 degrees will last years if not decades.
  4. Use the new EPA-approved nonpermeable hoses between the tank and the motor, because the fuel deteriorates less in them.  Replace them once they are 10 years old, including new ends and a new primer bulb (if you use one), because if they leak air you will be stranded on the lake.  Don't reuse the ends unless you replace the o-rings, eventually they will leak air too
  5. Consider switching to a metal tank or a nonpermeable plastic tank.  Some motors need to have a pressure regulator added for use with a nonpermeable tank or they will flood, because the pressure becomes elevated when the tank gets hot.
  6. Use two small tanks rather than one large tank to facilitate rotating fuel.  Or, use one small tank, and a safety can.
  7. Disassemble your fuel tank, clean the pickup screen, and wash the inside out with strong solvents every few years.
  8. Replace all the rubber and plastic fuel system components in your outboard every 10 years, that is, the fuel pump and all the hoses, and the fuel bowel and gasket (if equipped)
  9. Clean or replace the fuel filter in your outboard every year.  Consider adding a finer paper element filter if your outboard only has a screen.  Replace it often.
  10. I do not use Sta-bil or similar products because I do not believe they help to any material degree.  For boats the off-season is winter and the fuel will be fine without treatment.  For snowblowers and snowmobiles I try to end the season with as little fuel in the tank as possible because the butane fraction will be gone by fall and they won't start without starting fluid.
  11. Use ethanol-free gasoline if you can get it, because it improves your odds, but don't obsess over it.  Some very old fuel system parts will deteriorate quickly upon exposure to ethanol, but unless your motor is an antique and you use NOS parts, this does not apply to you.  The problem with ethanol is that it absorbs water, and once it has absorbed enough water the fuel will separate into two layers, one of watery ethanol and another layer with all the alkane fractions.  The water in solution with the fuel will also cause any steel fuel system components to rust, leading to particulate contamination.
  12. Be cognizant that in places where it snows the petroleum producers switch blends seasonally.  Winter gas has shorter alkane chains, all they way down to butane, to improve cold weather starting performance.  Winter gas has a higher vapor pressure as a result and will tend to evaporate in vented tanks in hot weather, and cause higher fuel system pressures in the new epa-compliant nonpermeable tanks, which are unvented.  It possibly deteriorates faster although sources vary on this and it may depend on what the producer has actually put in it.  Summer gas has exclusively the longer alkane chains and a lower vapor pressure, and if you put it in your snowblower in January then your snowblower won't start because the fuel won't vaporize in a cold engine.
  13. Turn off the fuel valve or disconnect the hose, and run the engine until the fuel in the bowl is exhausted, before storing the engine for more than a week or two.  The main reason for this is that you can start the engine with fresh fuel that hasn't been sitting in the carb bowl, where it is exposed to air and humidity.

In most places, there's a household hazardous waste collection facility that will accept old gasoline in reasonable quantities.  You can use an automotive repair type suction gun to transfer fuel out of containers and tanks safely as when dealing with small outboards that have integral tanks.  Do it outside, away from sources of ignition.

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I can't emphasize enough the importance of staying away from cheap plastic gas cans.  I switched to metal safety cans about 7 years ago and have had far fewer problems with fuel.  They are also better for fire safety both during storage and while filling or dispensing.

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How much do burn per season?  I only burn a few of gallons per year.  I try to use Tru-Fuel. I get it at Home Depot in the lawnmower section.  

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Thanks for the ideas.    

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7 minutes ago, silent bob said:

How much do burn per season?  I only burn a few of gallons per year.  I try to use Tru-Fuel. I get it at Home Depot in the lawnmower section. 

At $20 a gallon, it's a very expensive way to buy your gasoline.

Might be useful for things like snowblowers or chainsaws, which most people use less than 5 hours a year, and where summer storage is the problem.  But for a boat?

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6 minutes ago, 2airishuman said:

At $20 a gallon, it's a very expensive way to buy your gasoline.

Might be useful for things like snowblowers or chainsaws, which most people use less than 5 hours a year, and where summer storage is the problem.  But for a boat?

At only a few gallons per year, it pays for itself if i don't have to take it to the shop!  $100 minimum just for them to look at it!  I was a lot nicer when my outboard shop was literally around the corner from my office, but they moved and I moved.  Now 20 miles away, with heavy traffic.

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1 minute ago, silent bob said:

At only a few gallons per year, it pays for itself if i don't have to take it to the shop!  $100 minimum just for them to look at it!  I was a lot nicer when my outboard shop was literally around the corner from my office, but they moved and I moved.  Now 20 miles away, with heavy traffic.

In some states it's easy to find ethanol free gas at a pump, but other states it's hard. Ironically, in Houston it was almost impossible to find although the refineries were visible (and smellable). "I bet they are brewing up some sweet, sweet real gas there. Just won't sell it to me." Probably the same story in Jersey. Easy to find real gas in Oklahoma and Idaho. 

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I'm in an area that mandates the use of Ethanol blended Gasoline, but won't sell me Denatured Alcohol!

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I've had to clean the carb in my Tohatsu 8 a number of times, but it's never needed an actual repair.   All you need is a wrench and carb cleaner.  It takes minutes.

A new carb is quite a bit more expensive than a can of carb cleaner.  And taking the old carb off and putting the new one on is probably already half the work one needs to do to clean it.

If you are careful, you can probably re-use the existing seals.  The carb seals rarely seem to rip, unlike the water jacket or thermostat seals on the engine block.  Anyway, the seals are cheap from boats.net.  It wouldn't hurt to just have some as spares.

You can buy the tech manual for the engine.  Most work can be done with nothing more than some wrenches.

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As mentioned above use fresh fuel. I start with 1 gallon in the tank in spring amd add 1 gallon a month fresh from the pump..  We do Wednesday nights and a few day sails and regattas. Year end regatta involves a delivery so we add more. Spark plug on the small Nissan/Tohatsu/ etc is sensitive.  Replace it annually. Drill the brass plug on the beveled face on the carb top , remove the plug and turn the screw below 1/4 turn ccw. If you use alot of fuel each year,  add an ounce or two of naphtha to each gallon.

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I do a LOT of small outboard carbs. I have 2 sitting in the shop right now. Learn to take it apart, soak it in a gal can of carb cleaner (overnight is what I do), blow out all the passages with a spray can of carb or brake cleaner (same stuff). Blowing out all the passages is the important part. This works on 95% of the carbs and what I did for years. I now have sonic cleaner. Overnight running and it hasn't found a carb it couldn't clean.

If you can get ethanol free, do it. TruFuel is expensive but less than a mechanic, There are a couple of Walmarts around me that have it. Another source is aviation gas at your local small airport.

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@Warbird   Plugs.,,,  never bothered since I figured the motors have few hours.   I recall my dad replacing plugs on the evinrude in the 90s, I just clean and gap them each winter.   The Tohatsu probably has 50 starts since March but I don’t have a channel.   I bet it barely runs 15 hours a season with five in gear.   Add another 10 if I get a cruise, since the wind invariably dies.   I’ll correct that oversight and spoil the evinrude a bit too.   It’s cheap insurance.    Naphtha?   Like the mothballs hot rodders used to burn out their valves?

@2airishuman thanks for the education,   It’s been Missouri hot, so I probably baked the fuel even in the shade.   Also humid, and I sucked up some fog at night,    It’s too new of a system for most of your maintenance.   Is the expensive plastic tank that came with the motor ok?   It’s rust proof and it doesn’t scratch the gel coat.    Fuel filter is now on order.

Regarding ethanol free, I saved a penny and spent a pound by ignoring @silent bob solution this spring,   With Covid and no paycheck I bought road gas when I launched.    Early season mix may be as bad as the corn whiskey per 2air’s info,,    A local agriculture coop sells off road untaxed diesel but can’t get ethanol free gas.   Damn ADM.  

@F_L  Av Gas?  I was told the octane was crazy high.   I thought it would do something bad, I have no idea what.   I’ll call the airport.  

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52 minutes ago, Lark said:

@F_L  Av Gas?  I was told the octane was crazy high.   I thought it would do something bad, I have no idea what.   I’ll call the airport.  

High octane gasoline is less explosive. Unlikely to cause any damage except to your wallet. Buying from an airport is problematic because the fuel may be untaxed and selling it out the door could be a legal problem. However if a buddy drains it out of his airplane for an inspection....

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Here in 'straya we can get three types of fuel, the 10%ethanol, straight 91 octane or 98 octane.

I usually use the 98 in small engines.

Also I now sail a beach cat so don't have any problems with fuel!

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clean the carb yourself, it aint rocket science. but also check all the fuel lines. I had a brand new Honda 30 four stroke that gae me fits. biggest problem was the seal on the fuel filter, but there were also 3 or 4 other spots in the fuel line from the tank to the fuel pump that were sucking air. The primary system was cutting out in mid range throttle. it would idle and run wide open  pretty well.. 

 

good luck

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I picked up a used Honda that was running like crap and this fixed it. This does wonders for carbs that have the varnish like deposits modern gas can leave. 

Go to harbor freight and pick up their cheap ultrasonic cleaner ( 60 bucks) . Fill it with warm water and some Simple Green. Pull the carb off and drop it in the cleaner. My carb wouldn't completely fit under the water so I had to turn it a couple times. Run it through a couple cycles, take it out, rinse and put it back on. 

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I buy AVGas fromm the local airport.  $6 a gallon and no problems.   Make 1, maybe two trips a year with jerrys.  Use it for standby fuel for generator also.  Screw ethanol.

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Man I have the same motor. It’s got more hours of swearing at it than running. Put it down below for a race and it won’t start again for 24 hours. I’m sure it’s a fine engine, but has no place on a weekly raced sailboat. Especially for those of us with electric cars who’d like to go to the gas station once a year, or less!

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9 hours ago, Lark said:

 

@2airishuman thanks for the education,   It’s been Missouri hot, so I probably baked the fuel even in the shade.   Also humid, and I sucked up some fog at night,    It’s too new of a system for most of your maintenance.   Is the expensive plastic tank that came with the motor ok?   It’s rust proof and it doesn’t scratch the gel coat.    Fuel filter is now on order.

 

Your expensive plastic tank is probably fine.  The test is whether it gives off a good deal of gasoline stink on a hot day.  If it does, it's permeable, if not, you're good.  Same test applies to the hose.

If you can take the fuel tank off the boat between uses, and keep it (safely) in a cooler location, that will help too.  It's a hassle.

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3 hours ago, sail69 said:

I buy AVGas fromm the local airport.  $6 a gallon and no problems.   Make 1, maybe two trips a year with jerrys.  Use it for standby fuel for generator also.  Screw ethanol.

Nothing works better than 100 Low Lead in my Nissan 9.8.  But one gallon of gas from the local convenience store requires removing and cleaning the carb.  

 

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I have a tohatsu 6hp with a couple of hundred hours on it. Run the carb dry at the end of the day or before storage and you won't have any more problems. This topic comes up again and again and the solution remains the same. I also use Seafoam in the gas to try and absorb some of the water. The problem is caused by a carb sitting for a long period with gas in the float chamber. It absorbs water which then corrodes the jets and passages. No gas, no water, no corrosion.

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^^^This. I do this even with ethanol-free gas and it makes a world of difference. That said, I don't bother with doing on a daily basis when I'm cruising because my Suzuki 2.5 is so miserly it takes about 5 minutes of idling to drain the carb. :D

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Seafoam is alcohol. Chew on that cornundrum....

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I'm no expert on carb cleaning so I won't comment. I haven't had any issues with my 1994 Mercury 5hp 2-Stroke in the three years I've owned it burning Ethanol-free fuel through it and burning the carb dry before storing for anything longer than 2-weeks. I haven't done any maintenance other than the anode and gear oil.

Ethanol free fuel isn't too hard to find if you know which stations carry it.

This site has a list of stations searchable by area that have ethanol free gas: https://www.pure-gas.org/

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"Turn off the fuel valve or disconnect the hose, and run the engine until the fuel in the bowl is exhausted, before storing the engine for more than a week or two.  The main reason for this is that you can start the engine with fresh fuel that hasn't been sitting in the carb bowl, where it is exposed to air and humidity."

Been doing this for years really reduces the issues.  I usually have to give the engine a couple of light pulls to get gas back into the system but always starts and runs fine following this procedure.  I also close the gas tank air values after running it dry.  If fuel gets on the old side I usually just put it in my car tank and go get some fresh fuel maybe twice a year depending on use.

 

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14 hours ago, Lark said:

@Warbird   Plugs.,,,  never bothered since I figured the motors have few hours.   I recall my dad replacing plugs on the evinrude in the 90s, I just clean and gap them each winter.   The Tohatsu probably has 50 starts since March but I don’t have a channel.   I bet it barely runs 15 hours a season with five in gear.   Add another 10 if I get a cruise, since the wind invariably dies.   I’ll correct that oversight and spoil the evinrude a bit too.   It’s cheap insurance.    Naphtha?   Like the mothballs hot rodders used to burn out their valves?

@2airishuman thanks for the education,   It’s been Missouri hot, so I probably baked the fuel even in the shade.   Also humid, and I sucked up some fog at night,    It’s too new of a system for most of your maintenance.   Is the expensive plastic tank that came with the motor ok?   It’s rust proof and it doesn’t scratch the gel coat.    Fuel filter is now on order.

Regarding ethanol free, I saved a penny and spent a pound by ignoring @silent bob solution this spring,   With Covid and no paycheck I bought road gas when I launched.    Early season mix may be as bad as the corn whiskey per 2air’s info,,    A local agriculture coop sells off road untaxed diesel but can’t get ethanol free gas.   Damn ADM.  

@F_L  Av Gas?  I was told the octane was crazy high.   I thought it would do something bad, I have no idea what.   I’ll call the airport.  

 

1 hour ago, El Boracho said:

Seafoam is alcohol. Chew on that cornundrum....

Seafoam, like STP gas teeatment amd other Fuel injection cleaners are generally a mix of Isopropyl alcohol,  kerosene and naphtha .  The SDS reveals this though seafoam has edited their sds.

If you use 5 or 10% alcohol fuel,  you don't need IPA, lubrication is not an issue with carbs so you don't need kerosene.  The naphtha is the operative solvent in these products that dissolves the deposits.

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I used Sunoco Optima fuel for the first time this season after buying a new outboard.  It contains no ethanol and is 95 octane, so nothing extreme.  It comes in 5 gallon cans and costs about $70.  The cheap bastard in me screams, but it is cheaper than a mechanic down the road.  5 gallons will last at least a season, and Sunoco states it remains fresh for a couple years. 

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1 hour ago, 23feet said:

Run the carb dry at the end of the day or before storage and you won't have any more problems.

 

15 minutes ago, B dock said:

Been doing this for years really reduces the issues.  I usually have to give the engine a couple of light pulls to get gas back into the system but always starts and runs fine following this procedure. 

 

59 minutes ago, climenuts said:

and burning the carb dry before storing for anything longer than 2-weeks.

And here I thought I'd thought this up all by myself....

Add me to the ranks that swear by this. Anytime I'm shutting down for the day I just pull the fuel hose and let the motor run dry (only exception is at anchor). At the dock I do it with the engine raised and the muffs on so I can rinse the cooling passages, too. Makes me feel very smug.

Like other folks on this thread, I too was skeered of my carb for a long time - till I jerked that fucker off and got up in it. Then I discovered all the voodoo around it was just more hokum the 'necks use to keep a mystique around their stinky gas-toys.

Two other things to consider:

1) Get a real fuel filter and fuel/water separator. Easy install, mega protection.

2) If you go through fuel slow, use a grease pencil to mark your tanks with the date when you fill them. Then when you refill, take a spill rag, daub out a tiny bit of gas, use it to wipe off the old date, and repeat. Tuck the grease pencil behind your new fuel filter and go sailing.

 

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16 hours ago, Lark said:

@Warbird   Plugs.,,,  never bothered since I figured the motors have few hours.   I recall my dad replacing plugs on the evinrude in the 90s, I just clean and gap them each winter.   The Tohatsu probably has 50 starts since March but I don’t have a channel.   I bet it barely runs 15 hours a season with five in gear.   Add another 10 if I get a cruise, since the wind invariably dies.   I’ll correct that oversight and spoil the evinrude a bit too.   It’s cheap insurance.    Naphtha?   Like the mothballs hot rodders used to burn out their valves?

@2airishuman thanks for the education,   It’s been Missouri hot, so I probably baked the fuel even in the shade.   Also humid, and I sucked up some fog at night,    It’s too new of a system for most of your maintenance.   Is the expensive plastic tank that came with the motor ok?   It’s rust proof and it doesn’t scratch the gel coat.    Fuel filter is now on order.

Regarding ethanol free, I saved a penny and spent a pound by ignoring @silent bob solution this spring,   With Covid and no paycheck I bought road gas when I launched.    Early season mix may be as bad as the corn whiskey per 2air’s info,,    A local agriculture coop sells off road untaxed diesel but can’t get ethanol free gas.   Damn ADM.  

@F_L  Av Gas?  I was told the octane was crazy high.   I thought it would do something bad, I have no idea what.   I’ll call the airport.  

Octane only affects the knocking (pre-detonation).  It is otherwise the same gasoline.  Often the truck that delivers to the gas station has the same gasoline in both his trailers, and the octane additive is added in.  AvGas is usually devoid of alcohol, as it attracts water, water freezes, engine stops, and airplane fall out of the sky!  It is usually very high octane, as they run very high compression ratios.  

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57 minutes ago, silent bob said:

  AvGas is usually devoid of alcohol, as it attracts water, water freezes, engine stops, and airplane fall out of the sky!  It is usually very high octane, as they run very high compression ratios.  

Private aviation has an enviable record...

They never left one up there......

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11 minutes ago, warbird said:

Private aviation has an enviable record...

They never left one up there......

 

622CBF8C-AB7B-4420-A343-E039CE57042C.jpeg

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5 hours ago, 23feet said:

I have a tohatsu 6hp with a couple of hundred hours on it. Run the carb dry at the end of the day or before storage and you won't have any more problems. This topic comes up again and again and the solution remains the same. I also use Seafoam in the gas to try and absorb some of the water. The problem is caused by a carb sitting for a long period with gas in the float chamber. It absorbs water which then corrodes the jets and passages. No gas, no water, no corrosion.

As I said, I have religiously disconnected the fuel line after every single day / evening sail since before the last rebuild, letting it run until it starves.  I then lift the motor out of the water.  

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My Honda 40 engines will usually have an idle circuit plug up over the winter even though I run the carbs out of gas and drain them.

What works is to run Techron additive rich fuel for several minutes and then let them soak. Next day they are cured. I have tried other additives, Seafoam included, which did not help. 

 

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Not much to add to the above, but I'll share what's worked for me.

Cleaning the carb isn't hard, you should give it a shot. Berryman's B-12 spray is great for that and you can be done within a hour.  Soaking overnight is better if you have the time.  For me it's once at the beginning of the season and again if I notice problems towards the end of summer.

Ethanol free gas helps a lot.  Tru-Fuel and similar are pricey, but my consumption is low enough that the extra money is well worth it.

Seafoam with each new tank seems to help.

I never had much luck with sta-bil but others have recommended it.

Berryman's fuel additive likely helps too. I used it one summer with good results, but I think the seafoam is better for my situation.

In short, you need to put a little effort in, but it seems like it would be less than the time of your trip to the repair shop and less than $15 in B-12 and Seafoam.  If at all possible and financially justifiable, get ethanol free gas. 

 

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Follow on question for Tohatsu / Nissan 4.5 to 6 HP owners.   The service manual is on manufacturer back order.   I'm looking for a vender with old inventory.   When I pulled the carb I found three rubber hoses.  The large one is obviously the fuel line.   There were two on the top.   When I tried to disconnect them the tugging apparently pulled the far end of each of them off....something.   I can't figure out where they go or what they were supposed to do.    I don't think one / both were disconnected prior, causing my failure, but maybe.  

My next step is to pull the bottom cowling off and look for fittings hidden from view.    The boats.net parts diagram just calls them "fuel pipe 3mm".   I haven't found an PDF service manual from what appears to be a reputable source to buy.

 

 

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Prople who put corn squeezings in their little motors do do because they  simply love having engine trouble 

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19 hours ago, Lark said:

Follow on question for Tohatsu / Nissan 4.5 to 6 HP owners.   The service manual is on manufacturer back order.   I'm looking for a vender with old inventory.   When I pulled the carb I found three rubber hoses.  The large one is obviously the fuel line.   There were two on the top.   When I tried to disconnect them the tugging apparently pulled the far end of each of them off....something.   I can't figure out where they go or what they were supposed to do.    I don't think one / both were disconnected prior, causing my failure, but maybe.  

My next step is to pull the bottom cowling off and look for fittings hidden from view.    The boats.net parts diagram just calls them "fuel pipe 3mm".   I haven't found an PDF service manual from what appears to be a reputable source to buy.

 

 

Lark

On my six HP Tohatsu (2007), there are two rubber lines; fuel and PCV. I have attached two pics showing where the PCV attaches to the carb, and where the PCV attaches to the engine block, just above the oil fill cap. If you are dealing with rubber hose of smaller diameter than the fuel line, it sounds like vacuum tubing. My carb does not have vacuum tubing and I don't know why your engine would. My carb also has two throttle cables and a choke cable, which are cables that run inside a black jacketed tube, but the cables are inflexible and probably not what you are dealing with.

A few pictures of your situation would be helpful.

Snubs

 

Outboard_fuel_line_01.thumb.jpg.0cbe25043e07c40994f271fac33fc7d7.jpgA few pictures of

Outboard_PCV_01.thumb.jpg.537a12f3d693a1be1ddfacc2414617e5.jpg

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3 hours ago, snubber said:

Lark

On my six HP Tohatsu (2007), there are two rubber lines; fuel and PCV. I have attached two pics showing where the PCV attaches to the carb, and where the PCV attaches to the engine block, just above the oil fill cap. If you are dealing with rubber hose of smaller diameter than the fuel line, it sounds like vacuum tubing. My carb does not have vacuum tubing and I don't know why your engine would. My carb also has two throttle cables and a choke cable, which are cables that run inside a black jacketed tube, but the cables are inflexible and probably not what you are dealing with.

A few pictures of your situation would be helpful.

Snubs

 

A few pictures of

 

The PCV hooks to the air inlet.   If it was a 1970s car it would be vacuum tubing,    Looking at the motor in more detail I cannot figure out where the piss hole gets water from.   One hose fits in there perfectly.    Could they run the diverted coolant through the carb body for suction or something?.   If I blow on one it comes out the other.   That would mean the other hose must attach to the water jacket somewhere,    Damn if I can see a nipple.   The only manual I found so far was in Russian and doesn’t have helpful pictures.

DE788618-DC86-4CE7-8DCA-B2995D12F8A7.jpeg

DAA1D211-D13F-4FA9-AF4B-53899C066190.jpeg

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The fuel filter is off waiting a replacement.   012A3FAF-438C-42D1-A36F-556C7AB9BAA3.thumb.jpeg.1b34a38777ed07ccc56610b7a2a6dc8d.jpegThe carb is unbolted here.

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I found the manual by using the same key words on another device with a different search history.   It has excruciating carb details.   At the end (page 243j it discusses variants.   It appears I have a variant with two ‘vent tubes’.    It says to disconnect them, but not what they go to.  :wacko:    I wonder if they actually attach to anything.

http://www.tohatsu.pl/wp-content/uploads/2016/08/pdf/manual/FOUR STROKE/TOHATSU_4B-5B-6B_E.pdf

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On 7/28/2020 at 4:25 AM, Lark said:

My Tohatsu sailmaster 6 is in need of yet another carb repair and my redneck outboard guy decided his side gig was more lucrative then boats.   

Two questions:

1.    Should I repair the carb vs carb replacement vs driving 1 - 1.5 hours there an back (4-6 hours total) to go to a real shop?   I'm a basic shade tree mechanic but haven't messed with small engines much nor carbs.   I could probably swap a carb out for the time spent driving and not worry about shop hours conflicting with my work schedule.    I'm tempted to buy a new carb, buy a rebuild kit to rejet the old one during the off season, buy the service manual and stop being reliant on others.   'Solution 1 maritime' is the price winner with all of the above, if anybody can vouch for them.  I can buy a carb from boats.net (I've used them before).   I assume I would need a gasket too?    For years I trailer launched a smaller boat with a reliable Evinrude 2 cycle that works decade after decade with only routine winterizing, so I never actually had to know anything about outboard motors.   Its too thirsty and too wimpy to be a good primary on the pocket cruiser, but ends up being used as an alternate power source at least once a year due to mechanicals on the new Tohatsu.

2.  I'm pretty much stuck with ethanol.    My local marina sells road gas.   I do buy ethanol free when I get to travel.   I did everything the prior mechanic suggested.  The tank has seafoam and stabil.   I disconnect the fuel line and run the carb dry every single day.  I made it two years since the last rebuild (Third failure on a 4 year old motor).   I tried to run clean gas with seafoam after it died in the face of an approaching storm last week.   It idles but is unreliable under load and dies quickly at throttle (main jet per google?).   Since I occasionally do some coastal hops I need range.   Upgrading to electric isn't a good choice.   Any ideas on prevention, or should I just keep a second carb as a spare, pack it on trips and plan on swapping it out every year or two at an inconvenient time?  

My goal is to get the motor back in operation as quickly as possible.   Cost is secondary. 

Thanks 

 

  

 

 

 

 

can you get avgas, run that, problems over..

Those small Jap 4 strokes should give you a new carb in the owners toolkit instead of a spark plug

Once you take it apart put it in an ultra sonic cleaner, anything else is wasting your time.

Dont think blowing air though it is fixing anything, use a syringe or fuel squeeze bottle from model aircraft ship, you need to see liquid is actually following in the passages.

 

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Just now, Sailabout said:

can you get avgas, problems over..

Once I get it working I’ll burn corn free forever,   I noticed end cap displays at Lowe’s.   People are getting tired of carb problems,   I expect I’ll be much more self sufficient on small boat mechanicals as well.   

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5 hours ago, Lark said:

I found the manual by using the same key words on another device with a different search history.   It has excruciating carb details.   At the end (page 243j it discusses variants.   It appears I have a variant with two ‘vent tubes’.    It says to disconnect them, but not what they go to.  :wacko:    I wonder if they actually attach to anything.

http://www.tohatsu.pl/wp-content/uploads/2016/08/pdf/manual/FOUR STROKE/TOHATSU_4B-5B-6B_E.pdf

I think the change to version "C" is was to reduce emissions.  The fuel line from the pump to the carb was changed to low permeability.  I think the tubes are where the vents were, which let air into the carb fuel passages, and would let gas evaporate out.  The tubes going down probably help reduce emissions from gas in the bowl evaporating.  All the vents are supposed to have is 1 atm of air so they don't need to connect to anything.

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Stihl chainsaw.  Running rough and starving.

Took it back to where I bought it.  Said the crank seals were gone, $600 to fix or I could get a new one for $780.

Went to a bearing shop got seals for $20, youtubed the job (4 hours for me, about one for them) and the problem is still there. Cunts.

Took it back to the shop. they said it will be the carby then, can sell you a new one for $105.  Lost confidence in them understandably and ordered one online for $49. We will see of that fixes it but the agents can go fuck themselves, they just want to sell new shit.

Electric tools are looking pretty good against anything with a carby.

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4 hours ago, astro said:

Stihl chainsaw.  Running rough and starving.

Took it back to where I bought it.  Said the crank seals were gone, $600 to fix or I could get a new one for $780.

Went to a bearing shop got seals for $20, youtubed the job (4 hours for me, about one for them) and the problem is still there. Cunts.

Took it back to the shop. they said it will be the carby then, can sell you a new one for $105.  Lost confidence in them understandably and ordered one online for $49. We will see of that fixes it but the agents can go fuck themselves, they just want to sell new shit.

Electric tools are looking pretty good against anything with a carby.

I'd bought a bunch of Stihl stuff from the local farmer shop. Then I was having some troubles with a Tanaka leaf blower and went in to pick up a few bits to help sort it. The guys in the shop told me to bring it in and they gave me some help with it no charge. All I'd bought was a meter of fuel line, some carb cleaner and some grease...

I've been back there quite a lot as a result.

I have to say electric has crossed my mind a few times recently. I don't run my tools for hours.

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6 hours ago, xyzzy said:

I think the change to version "C" is was to reduce emissions.  The fuel line from the pump to the carb was changed to low permeability.  I think the tubes are where the vents were, which let air into the carb fuel passages, and would let gas evaporate out.  The tubes going down probably help reduce emissions from gas in the bowl evaporating.  All the vents are supposed to have is 1 atm of air so they don't need to connect to anything.

All this to find it was an engineering ‘practical joke’.  

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6 hours ago, astro said:

Stihl chainsaw.  Running rough and starving.

Took it back to where I bought it.  Said the crank seals were gone, $600 to fix or I could get a new one for $780.

Went to a bearing shop got seals for $20, youtubed the job (4 hours for me, about one for them) and the problem is still there. Cunts.

Took it back to the shop. they said it will be the carby then, can sell you a new one for $105.  Lost confidence in them understandably and ordered one online for $49. We will see of that fixes it but the agents can go fuck themselves, they just want to sell new shit.

Electric tools are looking pretty good against anything with a carby.

I just bit the bullet and bought a Makita 21" battery mower, string trimmer, blower, and grinder. The mower runs off two 18V batteries that are series-connected and it has space for four batteries so you can do a larger yard with the turn of a switch on the mower. I've got about 4000 sqft of lawn and it does the whole thing on two batteries. They're running a promotion right now where you get 4 batteries with the mower instead of the standard two (about $700+tax), so I bought the rest of the stuff cheap as "tool only".

I gotta say, I'm pretty impressed with all of it. The mower replaced a 5 horse Honda-powered 21" Troy-Bilt that would bog a bit if I let the grass get too long. This thing doesn't bog. In fact, the power management is pretty sophisticated. It's monitoring motor current or blade speed and modulates motor power to adapt to cutting conditions so at the other end of the spectrum it saves a bunch of power if the grass isn't dense. It's a lot quieter than the gas unit too, though I'm pretty careful with my hearing and still wear muffs.

The blower will easily run for 30 minutes on one (5Ah) battery and the string trimmer will seemingly go forever.

I would think a battery chainsaw is pushing the envelope as far as practicality because you're basically pulverizing a ~16" x 1/4" = 4 sq in block of wood whenever it's on. However, I was skeptical about the mower too. Turns out they've got a 4 battery deal on their 16" chain saw too:

https://www.amazon.com/Makita-XCU04PT1-Lithium-Ion-Brushless-Batteries/dp/B084ZVL534/ref=sr_1_2?dchild=1&keywords=makita%2Bbattery%2Bchainsaw&qid=1596292232&sr=8-2&th=1

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10 hours ago, astro said:

Electric tools are looking pretty good against anything with a carby.

I am in the process of replacing all of my corded electric tools, air tools, and portable gasoline-powered tools with battery ones.  Cars too.

High-performance lithium batteries have changed everything.

Like many, I learned how to work on cars on a Volkswagen Beetle back in the early 1970s with the help of John Muir's epic tome, "How to Keep Your Volkswagen Alive."  I've fixed engines, transmissions, cars, trucks, skid loaders, farm machinery, dump trucks, jeeps, ATVs, chainsaws, weed whips, lawnmowers, and boats for myself, friends, and family. Too many to remember, valve jobs, engine replacements, carbs, emissions controls, everything.

It's all a bunch of fiddley shit that requires constant attention and it's going the way of vacuum tube console stereos, the blowtorch, creosote wood preservative, and incandescent light bulbs. 

Milwaukee makes a fantastic electric chainsaw.  The reviews are fantastic even though they have a problem with the stud that holds the bar in place breaking loose, nobody cares, they get it fixed under the 5-year warranty when it happens and figure they'll buy another saw just like it at the end of 5 years.  These are landscapers who use saws all the time.  It is a small saw, about enough power for a 16" narrow-kerf blade.

One of these days I'll get one.  I have a Stihl 044, big saw, fantastic, carb requires attention now and again.  In a few more years someone will have an electric replacement for that, too.

Boat motors are going to be one of the last things to be replaced by electric because of the energy density problem, but the day will come.

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3 hours ago, IStream said:

I would think a battery chainsaw is pushing the envelope as far as practicality because you're basically pulverizing a ~16" x 1/4" = 4 sq in block of wood whenever it's on. However, I was skeptical about the mower too. Turns out they've got a 4 battery deal on their 16" chain saw too:

Makita and Milwaukee tools are made by the same company.  They are different tools for different markets, and the battery platforms aren't compatible.

The Makita side of the house has gone down the "multiple battery packs" road, as you describe.

The Milwaukee side of the house is very much committed to "one battery pack at a time" for portable equipment, and so they have this huge 200 wh pack that the chainsaw uses, along with some of their other landscape equipment and small stationary tools like chop saws.

The important thing for handheld equipment is not energy (watt-hours) but power, particularly the maximum number of watts the pack can deliver for the duration of a typical cut.  That, and making the electric motors smaller and lighter, is where the engineering effort has been going.  They don't state in their specs how much power they can pull out of their packs but I would guess that they are pulling at least 100 amps from the largest ones (like on the chainsaw), which would give them 2 HP at the shaft.

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On 7/30/2020 at 6:29 PM, Lark said:

Follow on question for Tohatsu / Nissan 4.5 to 6 HP owners.   The service manual is on manufacturer back order.   I'm looking for a vender with old inventory.   When I pulled the carb I found three rubber hoses.  The large one is obviously the fuel line.   There were two on the top.   When I tried to disconnect them the tugging apparently pulled the far end of each of them off....something.   I can't figure out where they go or what they were supposed to do.    I don't think one / both were disconnected prior, causing my failure, but maybe.  

My next step is to pull the bottom cowling off and look for fittings hidden from view.    The boats.net parts diagram just calls them "fuel pipe 3mm".   I haven't found an PDF service manual from what appears to be a reputable source to buy.

 

 

Not sure if it helps, but that same outboard is also branded as a Mercury. I can get you the service manual. 

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6 hours ago, IStream said:

I would think a battery chainsaw is pushing the envelope as far as practicality because you're basically pulverizing a ~16" x 1/4" = 4 sq in block of wood whenever it's on.

Yes maybe for the big stuff.  But I had people in here last christmas and they had two electric chainsaws, three batteries each and a fast charger.  Ran all day trimming and tidying.

I will get one for the small stuff.  I have a muscle injury in my back since yesterday from pulling the starter cord.

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5 hours ago, astro said:

Yes maybe for the big stuff.  But I had people in here last christmas and they had two electric chainsaws, three batteries each and a fast charger.  Ran all day trimming and tidying.

I will get one for the small stuff.  I have a muscle injury in my back since yesterday from pulling the starter cord.

I gotta admit, that $400 deal for the Makita saw and four batteries sounds pretty good...

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7 hours ago, 2airishuman said:
11 hours ago, IStream said:

I would think a battery chainsaw is pushing the envelope as far as practicality because you're basically pulverizing a ~16" x 1/4" = 4 sq in block of wood whenever it's on. However, I was skeptical about the mower too. Turns out they've got a 4 battery deal on their 16" chain saw too:

Makita and Milwaukee tools are made by the same company.  They are different tools for different markets, and the battery platforms aren't compatible.

The Makita side of the house has gone down the "multiple battery packs" road, as you describe.

The Milwaukee side of the house is very much committed to "one battery pack at a time" for portable equipment, and so they have this huge 200 wh pack that the chainsaw uses, along with some of their other landscape equipment and small stationary tools like chop saws.

The important thing for handheld equipment is not energy (watt-hours) but power, particularly the maximum number of watts the pack can deliver for the duration of a typical cut.  That, and making the electric motors smaller and lighter, is where the engineering effort has been going.  They don't state in their specs how much power they can pull out of their packs but I would guess that they are pulling at least 100 amps from the largest ones (like on the chainsaw), which would give them 2 HP at the shaft.

I like the Makita approach of putting a couple 18V packs in series. It allows you to use the same batteries in a huge range of tools, some with one battery, some with two. Their dual-station fast charger is nice too. It pumps cooling air through the packs during charging. 

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