Keel Bolts - 1975 Islander 36

Diverdown2u · #1 (**permalink**) 11-30-2011

The lifespan of 36 years has taken it's toll on this beautiful I36. As I was inspecting my keel bolts the other night - by just tapping on them I snapped off the exposed threads above the nuts so the bolts are now flush with the top of the nuts. These are the two bolts in the aft section of the bilge were a small amount of water collects on ocassion.

They obviously will need replacing soon when I yard the boat next spring to paint the bottom. (Good Timing).

In my research I have found that Islander made keels of both iron and lead. Mine is lead. They also molded some keelbolts instead of threading them. Thats an unknown as to what I have (threaded or molded) Does anyone have any insight on this?

Of course I will learn the hard truth when I haul the boat.

In the meantime I am going to ospho the bolts - seal them in 3M 4500 - and paint after they dry to slow down the deterioration. I have also stopped sailing the boat out of safety concerns although the rest of the bolts seem to be OK. Not worth the risk of losing the boat.

Does anyone have any suggestions on the best method of slowing the corrosion?

Oldsoul · #2 (**permalink**) 11-30-2011

I too have a 1975 I36. I'm not familiar with ospho but I'd make sure it's compatible with the paint or epoxy that you're going to coat the bolts with. I'd probably just clean up the bolts and paint them if they aren't stainless.

The biggest problem you may have is trying to replace the bolts. I don't have my specs with me at the moment, but I think the I36's with lead keels have J bolts cast into the keels which eliminates easy replacement. While looking for my current boat, I looked at and hauled a few Islanders. One was pretty good but had questionable keel bolts. Talking to the boat yard (it's a pretty reputable one), they said that I could add bolts, which they wouldn't do or tear into it. They said depending on the level of corrosion, they had a few options. They said they could 1) recut the threads if the corrosion was minimal, 2) add extensions to the stubs if the corrosion wasn't too deep into the bolts, or 3) drop the keel and recast bolts in place. Prices started at around 6k and could go up to 15k depending on what they found. The problem was that they wouldn't know what they had until they already started, so they said be prepared for the worst. The manager of the boatyard pulled me aside and said keep looking.

As for the option of adding bolts, there is a guy in California that will do it pretty reasonably. He was the builder of the original keels for these boats. I can't attest to his work but have his information if interested.

If you clean and paint the bolts every year, it should help considerably. Also, keep the bilge dry. On most of the islanders during that time period, the ice chests drained into the bilge. Mine doesn't have a shower but I could see that if any had a shower, it many drain to the bilge as well. I would eliminate the sources of water into the bilge (especially salt water) and be prepared to sponge out any water that does collect.

Diverdown2u · #3 (**permalink**) 11-30-2011

The only option I can afford is to have bolts added. Can you forward me the contact info to the person in SoCal that does this?

My ice chest and my shower (fresh water) both drain into the bilge (although I rarely use the shower). The ice chest just deposits a couple cups of water in it every few weeks depending on how I'm using it. That's why the aft bolts were the one's to go. The rest are OK (for now).

Ospho is a rust converter that reverses the osmosis. It works great on any metal. It does not fair well with fiberglass and non-epoxy paints. Should only use if you are familiar with the product.

Oldsoul · #4 (**permalink**) 11-30-2011

I PM'd you the info. Another option for the ice chest drain is to tie it into the sink hose. I haven't done mine yet, but it is on my list.

LakeSuperiorGeezer · #5 (**permalink**) 11-30-2011

On the Islander36.org site, there is a contact for a fellow who travels around repairing keel bolts. Not sure if he still does it. Keel Bolts

SloopJonB · #6 (**permalink**) 11-30-2011

Have you removed any of the nuts? Oftentimes the bolts are only corroded ABOVE the nuts and from there down are O/K.

Even in a worst case scenario and the bolt shears off, you still have enough to hold the keel on, especially since you aren't sailing.

You should have seen mine

There was NOTHING but rust and sealant holding my 10K Lb. keel on and it didn't even leak or crack the fairing.

GMFL · #7 (**permalink**) 11-30-2011

Quote:

Originally Posted by LakeSuperiorGeezer

On the Islander36.org site, there is a contact for a fellow who travels around repairing keel bolts. Not sure if he still does it. Keel Bolts

I called that guy about a year ago and he was still doing them.

To the OP... I believe that '75-'76 were the years that they used Iron for the keels and I don't think that guy above can replace those bolts. Maybe you got an early '75 so you should be good. Just FYI.

Oldsoul · #8 (**permalink**) 11-30-2011

Quote:

Originally Posted by GMFL

I called that guy about a year ago and he was still doing them.

To the OP... I believe that '75-'76 were the years that they used Iron for the keels and I don't think that guy above can replace those bolts. Maybe you got an early '75 so you should be good. Just FYI.

I found my Islander Info CD and checked the Islander 36 club's site. It looks like the early 70's had iron keels. They have a brochure for a 74 with an iron keel and a brochure for a 78 with an lead keel. The shoal draft 78 keel was listed as iron though. I think 75 or 76 was the year they switched the standard 6' keel to lead.

SloopJonB · #9 (**permalink**) 12-01-2011

Quote:

Originally Posted by Oldsoul

I found my Islander Info CD and checked the Islander 36 club's site. It looks like the early 70's had iron keels. They have a brochure for a 74 with an iron keel and a brochure for a 78 with an lead keel. The shoal draft 78 keel was listed as iron though. I think 75 or 76 was the year they switched the standard 6' keel to lead.

You should be able to test for it - get a very powerful magnet - a rare earth or something like it and put it in the bilge. If you have an iron keel it should display noticeable pull, even through the bottom glass.

Note, you need a STRONG magnet - fridge magnets, nut grabbers etc. won't be enough. Get one with 50 Lbs or more of grip.

Diverdown2u · #10 (**permalink**) 12-01-2011

Thanks everyone for the input. I wirebrushed the threads clean. Then a light coat of Ospho on the metal surface only and let dry. Coated with 3M 4500 seems to be all that is needed. The two bolts that sheared flush - on one of them the decay has started to saturate the core of the bolt, however the other is solid. Having looked at the Islander site and how these bolts are added - this goes a long way into solving the issue. I have to agree with SloopJonB that the keel is solid. Regardless of age. I dive the boat regularly and there is no indication that this keel is in jepordy. I'm just a firm beleiver in keeping things right. Cuts down on the maintenace cost later on. When I haul the boat next year I'll get more answers. I'll be sure to post when that happens.