Nuts!

[billyruffn]

I had always prided myself in being one step ahead of maintenance issues. You know, "Fix it before it's broke!" But, then we took our cruise to Maine.

A few days into the trip I found a nut in the bilge below the engine. Paint on the nut indicated it was from the engine. Origin? Not immediately apparent. I got out the mirror and worked my way around the engine -- No joy!

A week later, during the morning engine checks I put my finger on the engine belt to test tension and the alternator moved. Cause: nut missing from the bolt that holds the alternator on. No, t'was not the nut found earlier. Repair was simple with a new nut from the spares inventory and a quick replacement of the old belt that had been worn badly by the loose alternator.

Several days later on the way back to Cape Cod we stopped for the night in Gloucester. After dropping the anchor into the muck of the city's harbor, I asked the mate to put the engine in dead slow reverse to set the anchor. In response the engine errupted in a metal-on-metal racket that sounded like a chain around the prop banging on the hull. A quick engine shut-down followed by a visual inspection of the engine compartment revealed that all four nuts holding the shaft to the gear box had come off. The noise was the gear box flange banging into the ends of bolts in the flexible coupling. No, none of these four loose nuts were of the size of the one found in the bilge earlier in the cruise.

We spent the next four hours removing the flexible coupling form the shaft and then re-attaching everything with as much torque that could be applied given the wrench that would fit in the space was only 7" long. In the morning we were on our way again.

So....my question for the mechanics out there is: What's your method for finding loose nuts before an alternator or shaft falls off? At what interval should one go over the engine to tighten things up? I had always figured that once the nut was properly torqued (and in some cases with a dab of Locktite applied) that one needn't worry, but my recent experience suggests otherwise.

Any advice in this area would be most welcome.

And I still don't know where the first nut came from! Fingers are crossed that it's not critical.

[floatsome]

I check once a year, plus a quick feel of connectors when working on something. Just checked all 200+ nuts for the deck seam and hardware: labourious but worth it.

[tommays]

I like nylock nuts any place they can be used as even if the get lose they will NOT falloff compleatly

[AlanBrown]

Ain't no real way to check everything. Engine vibration, over time, can loosen lots of stuff that you thought was tight.

All you can do is check what you can before you leave , continue to perform daily inspections, have spares available, and hope for the best.

It's funny how we have this type of discussion all the time about our boats, but we don't think twice about jumping in our cars and driving hundreds of miles. Why doesn't stuff fall off them?

[LookingForCruiser]

You clearly have never driven my car...

[bheintz]

Originally Posted by AlanBrown

It's funny how we have this type of discussion all the time about our boats, but we don't think twice about jumping in our cars and driving hundreds of miles. Why doesn't stuff fall off them?

Either from necessity or misplaced bravado, people who ordinarily wouldn't touch anything under the hood of their cars, feel quite comfortable doing maintenance and repairs to their boat engines.

[SEMIJim]

Originally Posted by bheintz

Either from necessity or misplaced bravado, people who ordinarily wouldn't touch anything under the hood of their cars, feel quite comfortable doing maintenance and repairs to their boat engines.

I think it's partly those two and the fact that, for sailors, cars are often simply uninteresting .

Jim

[tommays]

Clearly you have never paid good money to a monkey to hack your boat up

There are plenty of GOOD craft people out there BUT it can be painfull weeding out the BAD

[timebandit]

Locktite on CLEAN fasteners will not come loose unless heated.

[WanderingStar]

I've had a similar problem. Everything seems to come loose on the engine. The shaft has come out of the transmission twice underway. Yesterday I repaired it again, also replacing the shaft oil seal (very difficult in such a tight space). One of the tangs on the nut locking mechanism was bent and damaged, I hope my repair lasts. Much of what I've retightened in the last 3 months has stayed tight though.