Check Your Lag Bolts And Engine Mounts

[maxingout]

This is what the lag bolts on my engine mounts looked like today when we pulled the engines. This is what 24 years and a circumnavigation can do to your lag bolts. My mechanic said that the only thing holding the engine in place was gravity, rust, and the grace of God.

[gjordan]

I have had 2 friends have their engines fall out of their beds (fall to one side during a tack). One was a hundred year old wooden schooner and the other was a Halberg Rassy 35. Both engines happen to be Volvos but that had nothing to do with it. Rotten wood and rusty lag bolts can ruin your day. Both of these happened on long passages and didnt cause too much water to enter the boat. Just lucky. HOW OLD ARE YOUR LAG BOLTS???? _____Grant.

[gamayun]

Wow, so lucky! This has been on my To Do list as it is probably the original set from 29 years ago and the mounts are looking tired...I shall move that up in priority

[maxingout]

Originally Posted by gjordan

I have had 2 friends have their engines fall out of their beds (fall to one side during a tack). One was a hundred year old wooden schooner and the other was a Halberg Rassy 35. Both engines happen to be Volvos but that had nothing to do with it. Rotten wood and rusty lag bolts can ruin your day. Both of these happened on long passages and didnt cause too much water to enter the boat. Just lucky. HOW OLD ARE YOUR LAG BOLTS???? _____Grant.

These are the original lag bolts put in at the factory twenty-four years ago.
There was no unusual vibration and no signs of a problem probably because we are a catamaran and the boat does not heel over. When I had my Westsail 32 and was heeling at 30 degrees, I don't think these lag bolts would have held the engine in place.

[maxingout]

Originally Posted by gamayun

Wow, so lucky! This has been on my To Do list as it is probably the original set from 29 years ago and the mounts are looking tired...I shall move that up in priority

Probably a good idea.

The lag bolts can look good from above and not be good inside the engine bed stringers as you can see in the picture.

[gjordan]

And if you remove lag bolts that end up looking bad, the wood they came from is probably just as bad. If the whole bed is not rotten, you might move the engine rearward and inch or so (if there is room) or rebuild the whole bed. Putting new lag bolts into rotten beds wont solve the problem for long. Just my 2 cents worth. ___Grant.

[a64pilot]

I had mine out last year, they are SS and looked perfect, and they are now 30yrs old. Mine are bolts, the stringers have nut plates.
I would suspect some wet, rotten wood looking at yours. Hopefully I am wrong.

[maxingout]

Originally Posted by a64pilot

I had mine out last year, they are SS and looked perfect, and they are now 30yrs old. Mine are bolts, the stringers have nut plates.
I would suspect some wet, rotten wood looking at yours. Hopefully I am wrong.

I will find out in the next couple of days.

[Chuck Hawley]

Originally Posted by a64pilot

I had mine out last year, they are SS and looked perfect, and they are now 30yrs old. Mine are bolts, the stringers have nut plates.

Same thing with my 20-year-old Alerion Express. Each of the eight bolts was easy to remove and was reusable. A good example of a boat that was built in such a way that it didn't have ticking timebombs of maintenance hell hidden in her bowels.

Thank you, TPI. Thank you, Carl Schumacher.

Chuck Hawley

[JPA Cate]

Hi, Dave,

Fwiw, I agree with A64Pilot, the timber is very suspect. All that rust and wastage.

Ann

[nhschneider]

In Don Casey's book, Inspecting the Aging Sailboat, he says that motor mounts shouldn't be lag-bolted into the stringer. He claims that a sturdy u-shaped bracket that fits over the stringer should be fabricated and that it should be through-bolted, with the motor mounts attaching to the u-bracket. It kind of makes sense but doesn't work on my boat as I only have access to one side of the engine stringer.

I just replaced my motor mounts (8 years old and about 3,000 hours) and installed new 316 lag bolts.

Fair winds and calm seas.

[boatpoker]

Lag Bolts ! a serious cheap out by the builder.
Wood gets wet, wood gets soft, engines vibrate, lag bolts get loose ... things start to move.

[maxingout]

Originally Posted by JPA Cate

Hi, Dave,

Fwiw, I agree with A64Pilot, the timber is very suspect. All that rust and wastage.

Ann

I have never seen anything like that before, and I will see what is happening to the stringers when I clean out the engine room now that the engines are out. It will be interesting to see what kind of shape they are in.

[maxingout]

Originally Posted by boatpoker

Lag Bolts ! a serious cheap out by the builder.
Wood gets wet, wood gets soft, engines vibrate, lag bolts get loose ... things start to move.

Since Exit Only is a catamaran that does not heel, it kept the engines from moving around most likely. There was never any unusual vibration to clue me in to the state of the lag bolts.

[maxingout]

Originally Posted by nhschneider

In Don Casey's book, Inspecting the Aging Sailboat, he says that motor mounts shouldn't be lag-bolted into the stringer. He claims that a sturdy u-shaped bracket that fits over the stringer should be fabricated and that it should be through-bolted, with the motor mounts attaching to the u-bracket. It kind of makes sense but doesn't work on my boat as I only have access to one side of the engine stringer.

I just replaced my motor mounts (8 years old and about 3,000 hours) and installed new 316 lag bolts.

Fair winds and calm seas.

Interesting idea. I don't know if it will work on Exit Only, but it sounds like a great idea.