Checking Keel Bolts

[Bill Shreeves]

I found the aft most bolt to be the most challenging to torque until I pulled the sole over the floor section above it and drilled a hole through the floor large enough for an extension. Now its easy to access and easy to hide.

[PaulJacobs]

I have three additional questions for those of you who have actually used a deep socket, an extension, and a torque wrench to torque the C34 keel bolt nuts to the recommended 107 ft.-lbs. 

(1) Were you able to manually apply sufficient force to the torque wrench to reach 107 ft.-lbs.?  Or, did you need to place a length of pipe over the torque wrench to increase the moment arm?  If the torque wrench is only just over a foot long then a force of 107 lbs. would be required.  That is probably at or near the limits of my capability at age 82.

(2) If you did use a piece of pipe - what length did you use?  Obviously, the longer the pipe the greater the moment arm and the smaller the force required.  However, if the pipe is too long then there are clearance issues (mast, bulkhead, base of the port settee, etc.).  I am thinking perhaps 2 - 3 ft. long might work nicely.

(3) How stable is this arrangement?  I am trying to picture the deep socket on the nut, a 9" or 12" vertical extension to clear the cabin sole, and a torque wrench on top of that being held by PFJ while I am sitting on the cabin sole.  Now, I pull (or push) clockwise as seen from above (depending on which bolt and where I have good access) with rather considerable force.  Does everything stay stable?  Or does the extension move from vertical and the whole business slips? :cry4`Is this really a two person job?

Paul F. Jacobs
Pleiades
1990 TR-FK
#1068
Yanmar 3YM30
FlexOFold 2 B

Fair winds and following seas.

[ewengstrom]

Paul,
I have arthritis in both thumbs and that makes handling tools....."interesting". I say that because I approach most jobs where pushing and pulling against said appendages with more thought than others might...and this would be one of those jobs.
I didn't find that keeping the whole assembly of socket, extension, torque wrench and myself in column to be a difficult task. I do think that Bill's idea of removing the flooring above those aft bolts is an excellent idea as those were the most difficult to access and creating that hidden access point would simplify the whole job immensely. 
As it turned out the keel boats on our 1988 weren't protruding above the nuts all that far so a standard deep socket slipped over them without any difficulty.

[PaulJacobs]

Hi Eric,

Were you able to achieve the recommended 107 Ft.-Lbs. of torque all by yourself even with arthritis in your thumbs?  Or, did you use a length pipe over the torque wrench?  And if so, what length of pipe worked best without bumping into everything?

Paul

Pleiades
1990 TR/FK
#1068
Yanmar 3YM30
FlexOFold 2B
Mantus 25

[Bill Shreeves]

Eric,
I have a Craftsman torque wrench and, if memory serves, I think its about 18" long.  It's not here for me to measure.  I found that sitting on the floor with my legs out and using an extension long enough to have the wrench above my thighs made it much easier for me.  Like rowing a boat.  Just take my time and get myself in to a comfortable position for each, hence the hole drilled in the floor for the aft most bolt.  If your sole is really slippery, put a rubber backed throw rug down.

[ewengstrom]

Paul,
The length of the average torque wrench makes reaching these torque levels quite achievable....even with bum-thumbs. 
My torque wrench is also a Craftsman and I've had it for years, I can't remember exactly but it's maximum torque setting is well above 107. I've torqued the head bolts on a few larger car motors and those get into the 130 (+,-) ft/lb torque range...and it will do those. I'd have to check but I'm sure its length is perhaps 20" or a bit longer end to end and this gives enough leverage to crank down on a bolt head with no pipe extension.
The point is you don't really need any custom or very special tools to do this, the boat absolutely does need to be out of the water and blocked up, and it'll take some leverage and very minor boat yoga to get at a couple of the more interesting nuts....but that suggestion to remove the floor panel and drill a hole over the harder to get at keel bolts is a winner in my book and I'll be doing that the next time I re-torque those keel bolts.

[waughoo]

Im curious to know why the boat need to be blocked up to check torque? 

[Stu Jackson]

Im curious to know why the boat need to be blocked up to check torque?

The concept, IIRC, Alex, is that you might find it hard to lift that much metal if it's just "hangin' there."

[waughoo]

That was my thought Stu.  Just wanted to know if there was some other specific reason.

[KWKloeber]

Im curious to know why the boat need to be blocked up to check torque?

Alex

Thread torque is related to (proportional to) the amount of stress that's on the body of the bolt (i.e., the tightness of the items being drawn together.)   Like a bungee around a stack of blocks -- if loose then the pull is easy.  As you add more blocks the stack gets the pull will get harder and the stack is drawn tighter together.  If you have to include the weight of the keel pulling the two halves apart, plus buoyancy counteracting that, then the torque specification of 107 ft-lbs is no longer valid.

I used a Craftsman "needle on scale" (not digital) torque wrench and had no issue -- my guess it was 24" long.  It takes holding the pivot point of the torque wrench with one hand (so the socket doesn't slip off) while pulling on the wrench.  Otherwise, the socket extension tends to tip at an angle, and that in itself can affect the reading.

"107" is REALLY not all that critical.  They need to be tight but the keel isn't going any place.  The hard mung between them isn't compressing one millimeter, and if it does there's a problem with the bedding (as there was with mine,) not with the bolt torque.  On the 30, as the wood embedded in the bilge rots (older mk-I hulls) owners have actually drawn down the nuts, compressing the fiberglass, and pulling the nuts/washers down into the floor of the bilge (if the load is not spread by using some widening plates.)

[Ron Hill]

Alex : The boat need to be out of the water blocked or your torqueing is trying to "lift" thousands of pounds of keel!?!?!   

A thought

[Ekutney]

I am planning to check my keel bolts when I pull the boat in spring.  Appreciate all the info, saves time, & money, learning from what others have done is just a good idea.

What is the best way to check if I have wood embedded below the bilge.  I have an early 34 #42 & am trying to determine what projects I may plan for.

[KWKloeber]

Ed
Pre '88 had wood.
http://c34.org/wiki/images/6/62/CTY_Pre-1988_model_Keel_Stub_Repair_-_Feb_1996.pdf

[waughoo]

Just got done torquing my keel bolts after making a custom deep socket.  My forward most bolt has a glass layup that is too close to fit the socket.  I will have to work on that at some point to make some room.  That said the middle four keel bolts took about 1/2 to 3/4 of a turn.  The rest took about an 1/8th of a turn.  I have a small smile at the front of the keel that makes me want to sort out the front bolt sooner than later, however, i'm pleased to have taken up what i did on the rest of the bolts.

[Jim Hardesty]

Sounds about what I got with Shamrock.  If remember correctly had to use a universal socket extension on one or two of mine.

https://www.northerntool.com/shop/tools/product_200805538_200805538

The deflection was little so I'm confident of getting the right torque, or close enough for me and I'm fussy.
Jim