Out West

Engine Swap Anarchy - Gas Palmer to Yanmar 2GM

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I have learned many things here, but now draw your attention and feedback on an engine swap.  Updates to be as sporadic as the progress…

The basics:  The gas Palmer 27 engine is the original from 1961. The prior owner had no issues and had it professionally maintained, with a new fuel tank, filter and pump back maybe 5 years ago.  Engine ran when parked, but I don't want to put the family aboard and have this museum piece crap out at the wrong time, and parts are rather hard to find.

 I have a decent Yanmar 2GM10 of unknown hours that I got from a character in Huntington Beach.  We bench ran it at purchase, sounded/looked good no smoke started up fast. Going from 8 hp to 13 may help, but ditching gas, and increasing reliability is the plan.

I plan to reuse the tank, but it will need a return line added (based on reading Yanmar install manual)  1050687313_Yanmar2GM.JPG.5bca9c96e390c8aa533a1d48026377bb.JPGweb-palmer-1.thumb.JPG.afc418391fb551b027dd8b519fe59968.JPG

Unknowns: The exhaust route, transmission linkage, prop, and who knows what else?

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- exhaust SIZE may be bigger for a diesel

- transmission output flange height compared to engine bed height. The Yanmar 2GM and 3GM with Kanzaki transmissions have the output of the transmission the exact same height as the engine mounts in their intermediate position. This makes it very easy to make a plywood jig from the drawing showing the engine feet position and position of transmission output flange

- engine bed width

- gearbox linkage lever throw direction

- gearbox reduction may be totally different; engine RPMs will be, so prop likely will be.

- gearbox output flange not mating with your shaft coupling; the Yanmar doesn't follow any SAE standard. You need a spacer or a new coupling made for your shaft.

- tee into the fuel tank vent hose for the return line, don't need to drill another hole in the tank. Use SAE J1527 hose

- for god's sake pull the fuel tank and clean it very very carefully. Steam cleaning is best. Maybe a car detailer after you have emptied it and let it air out for 2 weeks.

 

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Thanks for those tips @Zonker that is exactly why I posted up...I knew there were a lot of details to figure out that wiser folks would know already.   I am working on getting the old Palmer out right now.    The boat was sailed hard for many years, lot of stories I am sure.  Near as I can tell, that red funnel was the head.  I got things out of the road and cleaned and realized it goes straight to a through-hull.web-palmer-2.thumb.JPG.fc9924f2cce0e210ba8f5cf67be63ede.JPG

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12 hours ago, Zonker said:

- tee into the fuel tank vent hose for the return line, don't need to drill another hole in the tank. Use SAE J1527 hose

My return line has a pickup tube on it, which I was told stops "foaming". Is that just an old wives tale?

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and it might be a tad heavier than the gas engine so, maybe, the balance of your boat will change a bit...

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3 hours ago, andykane said:

My return line has a pickup tube on it, which I was told stops "foaming". Is that just an old wives tale?

It's common practice in commercial fuel tanks to have a small hard pipe inside the tank to direct the return fuel against the tank wall to reduce this. A pickup tube returning to near the bottom of the tank does the same thing.

Diesel does foam a fair bit - but the amount returned by a small Yanmar will be in teaspoon per minute i.e. a trickle and foaming won't happen.

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My Dodge RAM truck with Cummins 5.9L has an interesting arrangement. The return line is aimed at the pickup screen. The flow rate back to the tank is pretty high and comes out of the return line with some force. I assume this arrangement is intended to blast any transient clogs from the screen if there's a lot of stuff floating in the fuel. 

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6 hours ago, Zonker said:

Diesel does foam a fair bit - but the amount returned by a small Yanmar will be in teaspoon per minute i.e. a trickle and foaming won't happen.

On my 3gm it’s barely anything. I ran once with the return line going to a bottle for about an hour and it collected maybe a teaspoon of fuel. 

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You'll be fitting a good quality diesel filter.

Get one that has two inlets and run your return line to the filter.

That's also a way of avoiding the danger with two tanks, where you may be sucking fuel from the starboard tank and having the return line going to the port tank, which will overflow if you're lucky, or bust the tank if a bug has taken up residence in the breather.

I've seen diesels that returned more than 50%, don't know about your 2 GM.

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I suspect Yanmar, like most diesel engine manufacturers, would frown on that idea. Eventually you'll be heating up the fuel pretty hot in the filter. Returning to talk allows it to cool.

The way to make sure you don't suck a tank dry or overflow is (a) always take and return from same tank like a day tank (b) have 2 three ways valves side by side. One is the supply from tank, one is the return from tank. Have a mechanical bar linkage that makes sure valves are always changed to same tank in unison

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There's just one  tank mounted dead center aft of the engine, I think I'll take Zonker's advice and run to the vent line.

As far as I can find out, the Yanmar weighs about the same as the Palmer, I'll put them on the scale and see how they compare though.  3 day weekend coming, may at least get the Palmer out of the way if keeps raining (if it's nice...delay of project so I can get outside)

 

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The saga continues....it's out (solo job with strategic use of a forklift) ...and now to clean up the bilge.   What's the preferred method of grease/gunk removal in a engine bed area? 

I'll try wipe up with simple green and then see if something else is needed.  It looks like the existing beds will need changes to hold the Yanmar, as it's a bit longer due to the isolation mounts.

 

web-engine-out.JPG

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It's no fun and requires strong chemicals and safe disposal. 

Then, paint with a bilge paint and you'll feel much better about it over time.

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Simple Green ain't gonna cut it except maybe the last lap.

You'll' need solvents as Raz'r notes - lacquer thinner would be first on my list.

Then strong degreasers - I've had good luck with Zep products.

When you think you're done, spritz it with water - it will bead which means it ain't clean so keep going. :D

You have to do it that way or you'll sand contaminants into the surface and then you've really got a problem.

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10 minutes ago, SloopJonB said:

Simple Green ain't gonna cut it except maybe the last lap.

You'll' need solvents as Raz'r notes - lacquer thinner would be first on my list.

Then strong degreasers - I've had good luck with Zep products.

When you think you're done, spritz it with water - it will bead which means it ain't clean so keep going. :D

You have to do it that way or you'll sand contaminants into the surface and then you've really got a problem.

Yeah, when we cleaned out the grease of 30 years, I think it was Zep Professional. Not cheap, but worked. We had 10 gallons of toxic waste to dispose of.

 

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I'll match your benign snake oil with my benign snake oil:

https://www.quicknbrite.com/

I've used this stuff for years and it's never failed. Buy the tub of paste, mix with warm water, scrub with a stiff plastic brush, wait, scrub again, rinse off. Tar, wax, 100 year old cosmoline, it doesn't matter. I bought a gallon of it in 1990 and still have 1/3 left.

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Excellent - just what I was looking for in suggestions, figured acetone was a bit too much for the first try. I'll have at it with Superclean and Zep as both are on the shelf at Walmart/Home Depot (walking distance from boat) and see which works better.  QuicknBrite via Amazon pending.    59 years of gunk down there...but it's only a few square ft of surface.

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Just a reminder - when you think it's squeaky clean, spritz water on it.

It will almost certainly bead up which indicates it isn't clean.

You'll never get the water to sheet off but you want to get as close to that as you can.

Cleaning it over & over & over is the only way to get bilge paint to eventually stick.

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This scraping gunk out task is not fun, had a gallon of NAPA degreaser to test while waiting for the SuperClean to arrive.  Weighed out the engines, the Yanmar will add about 50 lbs.  I think I can balance it out as the water tanks are also 58 years old  and I'll pull at least one out and then could shift it forward.

 

engine_comparison.JPG

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5 hours ago, Out West said:

This scraping gunk out task is not fun

Agreed. I just got my shaft out and V-Drive off so now I'm scraping out the gunk. I figure at least some of it dates back to the boats build.

Just getting started on the first go round took 1/2 roll of paper towels and a spritzer of ZEP degreaser.

Several more days to go I'd say before I can mod the engine beds and paint. :blink:

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