Keel Bolt Condition?

[Clark]

I'm going to look at an older Capri22 this weekend and the owner has sent a number of pictures in advance. Here is one picture of the keel bolts. My question; are these OK, Bad or . . . . ? If unsure, how best to check them?

 

[Steve Dion]

Looks like a dirty bilge to me!

It always amazes me that people try to sell boats and do not clean them up prior to someone looking at it.

"You only have one chance to make a first opinion"

 

[Clark]

Yea, I wasn't impressed with that but if the bolts are sound, I can clean that up in 30 minutes or so.

Anyone have thoughts on the keel bolts?

 

[PaulK]

The bolts in the picture look fine. The problems with keelbolts aren't visible. Crevice corrosion happens down inside, where water may have gotten in between the hull and ballast. In order to check this, you have to remove the bolts. People usually remove one, and if it looks questionable, they keep going. If this boat hasn't had any obvious major repairs due to banging into something HARD, like getting dropped off the hoist, or hitting a rock at 8 knots, the keelbolts are probably fine. If the boat is 20 or so years old, they probably don't need checking. See if you can tighten them up at all, or if there's any "gap" between the hull and keel. Those two things might indicate an issue worth delving more into. Generally, keelbolts are pretty solid.

 

[kloudie1]

I dunno, Clark.. A rust trail, like that around the right most of the two in the middle sometimes can be a sign of crevice corrosion in stainless.. I think I would talk to a surveyor about that one in particular. If it is obvious that the rust stains are from something else, then it should be OK..like a plain steel washer under teh nut rusting from bilge water.. The surveyor may suggest pulling that one nut to look. Not saying that is what it is, it just looks like one I'd want to inspect a bit closely..

 

[Joe]

I think they look pretty good. I've seen rusted nubs that would break off if you put a wrench on them.... It actually looks to me like they are replacements... why don't you ask the owner? I'd be interested.

 

[jibes138]

Dirt or rust?

A little tough to tell from the picture but the washers under the nuts look like they are a cheap carbon steel and that is what is rusting and making the big mess. If the boat is on the hard take a nut off and remove the washer, see if the bolt is ok then you can replace the washers with stainless or if the stud is long enough make a backing plate to spread the load better than a small washer. Remember stress is force divided by area so increasing the area that the load is applied reduces the stress on the fiberglass.

 

[Clark]

Thanks for the input guys . .

I zoomed in on the original image and it does look like the middle washers are plain steel. I plan to inspect the boat Sunday and will go over some of the things with the owner you guys suggested (replacements/repairs, etc) and dig around that area with a small screwdriver. The boat is in the water but I may still get permission to remove one of those nuts to see what is what. I think the guy who did the survey on our 280 is from that area so I may give him a call as well and see if he'll do a mini inspection.

 

[RichH]

A little tough to tell from the picture but the washers under the nuts look like they are a cheap carbon steel and that is what is rusting and making the big mess. If the boat is on the hard take a nut off and remove the washer, see if the bolt is ok then you can replace the washers with stainless or if the stud is long enough make a backing plate to spread the load better than a small washer. Remember stress is force divided by area so increasing the area that the load is applied reduces the stress on the fiberglass.

Correct .... you cant assay if crevice corrosion nor developing fatigue
failure by 'just looking'.

If this boat 'sings to your heart' in all other aspects, make an offer and add a 'contingency to the agreement':
..... "that the keel bolt nuts are to be removed one at a time and tested for integrity by an accredited marine surveyor, the bolts will be lubricated, ..... and the bolts must withstand 85% of their OEM torque value. Any bolt that fails before 85% of the OEM torque value will be cause for rejection and dismissal of the contract/offer in its entirety", etc.

If there is any crevice corrosion or developing fatigue failure ..... torquing (properly with lubrication) the bolts to 80-85% of their rated torque value will quickly show if they remain 'intact'. Such a boat 'should' have the OEM design with a safety factor included in the OEM design that should be 2 or 2.5X greater than the expected 'service' design. You might want to contact the builder for that 'factor of safety' value, then you or your surveyor can quickly ascertain the proper torque value .... then load to 80-85% of that value.

 

[bffatcat]

keel bolts

Cant really tell much from a picture. You have to remove one or more bolts for inspection
hire a surveyor

 

[tommays]

I would want to know the age and look into if it has a plywood keel sump like the other larger pre 1981 boats in the line ?