Exhaust bolts keep coming loose

[myfirstboat1984]

I own a 1984 18' Wellcraft, 4C 140. When I first bought this boat a months ago, I took it out, and on the first day, filled the Bilge with water and had to be towed back to the dock. Turned out that there were four screws that secure the exhaust pipe to the back of the boat (forgive me, I don't know the technical names of these parts). Three of these screws were complete off and one was barely hanging on. I was pumping water from the lake into the boat. A nice gift from the previous owner to me!

Got home that day, found the problem, tightened all four bolts, and for a month now, I have had no water. Yesterday, I noticed a slight trickle and I had to pump the bilge a couple times in a couple hours. Turns out that these bolts are coming loose again.

The question is do I need new bolts, are there lock washers missing, or should I put some kind of compound on them to lock them in tight? It wasn't easy to get them all tighten the first time, and I don't want to have to do this again for a third time, so some advice would be great. Thanks!

 

[Gary H NC]

Re: Exhaust bolts keep coming loose

Maybe buy some new bolts and use some Loc-tite on them..

 

[mkast]

Re: Exhaust bolts keep coming loose

Take a look in the parts manual, see if lock washers are required. Use the correct size tap to clean the threads. Use some blue Loc Tite on the bolts. Remember, using more Loc Tite doesn't secure to bolt any better.

 

[JustJason]

Re: Exhaust bolts keep coming loose

found the problem, tightened all four bolts,

Did ya replace the gasket when you tightened all four bolts? They are 1 time use only.

Get a new gasket, get a torque wrench, and tightened the bolts down to spec. Replace the bolts if the threads are buggered. Use some blue loctite if it makes you feel better to.

 

[myfirstboat1984]

Re: Exhaust bolts keep coming loose

Cool, I didn't know about the gasket. I want to replace it, but there's not much room to see what's going on down there. After I remove the four bolts, should I be able to get the new gasket around and behind the plate? I am worried about needing to loosen other things to get the exhaust pipe to move around for me. Don't want to get in over my head, so if you have any more advice on that, that would be great.

 

[JustJason]

Re: Exhaust bolts keep coming loose

head up to the adults only section and download the manual for your engine. the entire procedure is in it.