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15 minutes ago, crankcall said:

I need to tighten keel bolts, what socket / wrench / whatever is easiest with a deep sump fitted keel ?? thanks

 

Why do you think you need to tighten your keel bolts?  Did you recently loosen or remove the keel? The ability to tighten old keel bolts does not make it any more secure. There is conflicting evidence that says you should although many here can't leave an unbusted nut alone. Tightening bolts may in fact break older fiberglass and mess up the joint. Doing so is at your peril as you may actually break bolts in this additional stress test.

 

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I've been told with C&C's of a particular vintage the torque settings should be checked every few years , I would think mine have never been checked in 20yrs, I knew the previous owner. 

I just cant figure out what tool fits down the sump to check the torque

I have been told by other owners after 40yrs things have been known to loosen up ?

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26 minutes ago, crankcall said:

I've been told with C&C's of a particular vintage the torque settings should be checked every few years , I would think mine have never been checked in 20yrs, I knew the previous owner. 

I just cant figure out what tool fits down the sump to check the torque

I have been told by other owners after 40yrs things have been known to loosen up ?

The correct method would be to drop the keel, check the bolts and remount. Most prefer not do that as it opens up a bigger expense to the bottom job. Tightening the bolts could help or hurt considering the vintage. 40 years is a long time and who knows who did what when sailing and where the boat was parked. A tap ring test with a pin hammer and a stethoscope listener on the inside/outside can give you an indication of the bolts and their security. I would do the sound test and avoid the tightening. In the future plan on a haul out with a keep drop review for peace of mind. If the bolts are good, it is only a few hours of work to drop-examine, tighten and replace the keel joint. Until then keep an eye out for bolt weeping.

Also note as some boats age, more folks and the yards they go to are drilling and using lags in a belt and suspenders insurance approach to keep boating affordable and yard bills to a minumin. Tightening a lag bolt that looks like a keel bolt could make a problem. 

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Boat is sitting on the hard, I could drop the keel this weekend . So back to my original question , what tool goes down into a 12" sump and can be turned in the hole to loosen a keel nut?? 

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Appropriately sized socket (probably need a deep socket) on an extension with a torque wrench on top.

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The fact that you are asking such a basic question sort of indicates that you might be best to get a more experienced person to do it.

Breaking or stripping a keel bolt in a lead keel would be an expensive disaster.

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Its not that basic a question , a deep socket hits the bolt before its onto the nut , there is about 3 1/2 " of thread showing above the nut, maybe a 3/4" drive socket would let the bolt come up through the socket, but now there is no place to put an extention.  I was considering a crows foot wrench but thought there must be something easier, I'm guessing the manufacturer had a socket on a pipe or similar? 

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35 minutes ago, crankcall said:

Its not that basic a question , a deep socket hits the bolt before its onto the nut , there is about 3 1/2 " of thread showing above the nut, maybe a 3/4" drive socket would let the bolt come up through the socket, but now there is no place to put an extention.  I was considering a crows foot wrench but thought there must be something easier, I'm guessing the manufacturer had a socket on a pipe or similar? 

Still a basic question and you have pretty much answered it for yourself. Get out your welder and create a socket to create an appropriate depth. But why the fuck is there 3 1/2 inches of exposed keel bolt? Seems excessive.

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Guess I'm digging the mig out of the shed and making a really long socket.  C&C built these things on an assembly line but it was largely a hand build, somebody probably set a bolt in the pour mold too high and somebody else said the keel sump is 12" deep , leave it. They built great boats , the production boats were just that, production boats. 

Thanks for the help folks

 

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How about a cutoff wheel in an angle grinder?

Trim them down to a more workable length, sand the cut edge to deburr it and you should be good to go..

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The right way to retorque the keel bolt nuts is to loosen them off first. It also gives you a chance to check the parts of the bolt that are hidden.

Then tighten the nuts to recommended torque. Depending on the size of the boat, you may need to rent a torque multiplier.

The numbers here are from the C&C Photoalbum. http://www.cncphotoalbum.com/ A major source of C&C info.

These numbers are for unlubricated nuts, if you lube them then you will have to do some research to find the new torque numbers. 

999325863_Screenshot_2021-03-09KeelBoltTorques.png.109601525621fe52bd1faead93b48cdb.png

 

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Hmmm, my 1/2" drive torque wrench only goes to 250, which is what I need on 3/4" bolt. Top of its range , but its a keel bolt not a cylinder head.  Now I just have to decide if its a cutoff wheel and rust bits everywhere in the bilge or buy the extra deep socket for $50 for a one time application. Leaning towards Mcmaster-Carr extra deep, i hate that black crap that gets everywhere off a cutoff wheel.  

Thanks Ishmael 

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You can probably rent a tourque multiplier, high tourque or a 3/4 tourqe wrench, they go up to 480 or 500ft lbs if I remember right. If you decide to trim them make a cold cut sawzall or porta band if it will fit.  As long as you have a drop cloth down no rust.

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On 3/9/2021 at 7:49 PM, crankcall said:

I need to tighten keel bolts, what socket / wrench / whatever is easiest with a deep sump fitted keel ?? thanks

 

First you remove the keelboat nut 

then you clean the threads 

then you lubricate the threads with tefgel 

then you reseat and torque the nuts 

torque settings are meaningless if  the nut , bolt are fouled and high friction 

obviously you don’t remove all the  keel boats at the same time , start from the middle .. remove , clean  , reseat 

re torque  to final setting once all bolts have been reseated 

if your situation requires a long socket extension you should fabricate a wood guide for the extension  to help keep the socket perpendicular to the nut and avoid rounding the head 

nothing wrong with  new nuts and washers 

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14 minutes ago, gbkersey said:

Large crowfoot wrench like this with some extensions.....

 

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Normally you buy a cheap socket and a length of the appropriate diameter steel pipe 

cut the socket in half with a grinder 

Then weld the socket to one end and weld the drive to the other 

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7 hours ago, slug zitski said:

First you remove the keelboat nut 

then you clean the threads 

then you lubricate the threads with tefgel 

then you reseat and torque the nuts 

torque settings are meaningless if  the nut , bolt are fouled and high friction 

obviously you don’t remove all the  keel boats at the same time , start from the middle .. remove , clean  , reseat 

re torque  to final setting once all bolts have been reseated 

if your situation requires a long socket extension you should fabricate a wood guide for the extension  to help keep the socket perpendicular to the nut and avoid rounding the head 

nothing wrong with  new nuts and washers 

Published torque settings are meaningless if you lubricate the threads.

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Slug, at least acknowledge you're wrong. Again.

Yeah, the difference in torque between lubed and non-lubed is huge. Look at that chart 680 vs 900 ft.lbs 

In industry if it's critical you use "rotation of nut" measurements or you stretch the bolt with a bolt stretcher and just snug up the nut almost by hand. When you release the bolt it's perfectly torqued.  Cylinder head bolts are often "tighten snug and then 3/4 turn" sort of thing.

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2 minutes ago, Zonker said:

Slug, at least acknowledge you're wrong.

horses and water ...

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3 minutes ago, slug zitski said:

In addition,  stainless keel bolts are prone to galling 

When working with stainless  and tefgel or other assembly paste is not available , Loctite with ptfe is a good substitute 

some folks prefer it because it is also a thread locker 

3810AA2D-1706-4DC7-B5C6-CFA021DF77FD.png

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Good lord, dry and lubricated torque values have been around forever. As Z said flats and stretch have also been around forever. MAK actually shows stick men at full and half figures plus a big ass wrench.

Almost all big shit is hydraulic stretched to a value and the nut tightened by hand. By far molycote is the preferred lube. Of I was doing keel bolts it's what I would use.

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34 minutes ago, SASSAFRASS said:

Good lord, dry and lubricated torque values have been around forever. As Z said flats and stretch have also been around forever. MAK actually shows stick men at full and half figures plus a big ass wrench.

Almost all big shit is hydraulic stretched to a value and the nut tightened by hand. By far molycote is the preferred lube. Of I was doing keel bolts it's what I would use.

Yes 

consult the torque tables 

the boat yard generalization for lubricated stainless to stainless is to reduce torque by 20 percent to achieve the desired clamping force 

do not mate stainless to stainless without assembly paste 

528B1669-A40D-4921-BBBA-185E1CE573A4.jpeg

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While you can use a crows foot accurately with a torque wrench if you do it right, the chances of getting 250 ft lbs on a crows foot without it breaking (or rounding the flats) are pretty remote. You need a socket. 

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1 hour ago, Zonker said:

 Cylinder head bolts are often "tighten snug and then 3/4 turn" sort of thing.

Whereas keel bolts are "Use a piece of pipe on a wrench and tighten until the suckers scream"

I'd say precision on cylinder head bolts is way more critical than on keel bolts. Very easy to bugger a laminated head gasket by improper torque sequence.

 

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^ the sequence Z references is actually quite accurate.  More about lack of tooling older stuff etc,. It actually gets pretty complicated in torque values using mechanical stretch vs hydraulic.  Some older mod sized engines didn't have the tooling at manufacturer so it was all mechanical, to a value plus so many flats would achieve a universal result.  Doesn't seem to be anything wrong with following a manufacturer OEM reccomended process. The danger would be straying from that to a universal value based on fastener size.  If the builder spec re tourque at X value after x amount of time sure. But of it's random internet knowledge saying do this then I would have some concern.

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The exact torque of keelbolts is probably not all that critical for most boats, the advantage of using a torque wrench is that you can see just how undertorqued they probably were.  Even a modest sized boat will have 3/4 or 7/8 bolts, some pretty small ones have 1". If you torque to the tables above that is around 700 ft lbs, not humanly possible without a torque multiplier. Using tables intended for construction or heavy equipment may not be advisable when the clamping material is fiberglass with compressive strength a fraction of steel though.

(I'll also point out you must read the fine print - the table Sloop posted above is for Grade 8 bolts, which are nothing at all like your keel bolts which you hope are 316. 316 yields at 35 Ksi, Grade 8 at 130 Ksi, only a 4x difference....)

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12 minutes ago, DDW said:

(I'll also point out you must read the fine print - the table Sloop posted above is for Grade 8 bolts, which are nothing at all like your keel bolts which you hope are 316. 316 yields at 35 Ksi, Grade 8 at 130 Ksi, only a 4x difference....)

I just threw that up to counter Sluggo about the lubrication thing.

There are tables for S/S. bronze, fine thread, coarse thread, you name it. They are guaranteed to be better that the typical "heave on it as hard as you can" method.

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316 and silicon bronze are going to be about the same as the strength is similar. A very few boats have duplex stainless and you'd want to look that up as torques would be higher. My boat is the only one I know of with K500 Monel bolts and Nitronic 60 nuts - which are as strong as Gr8 bolts. But I didn't torque them to 500 ft-lbs. Bolts really only need to be torqued to a preload above the cyclical stress value to be fatigue proof. 

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