Can exhaust Gaskets be replaced while in water

[Pst76]

Have a leaking exhaust gasket on a 5.7 V8 merc. Boat is in the water at Marina. Is it possible to change while in the water or best to take out of water. <br /><br />Thanks

 

[rbezdon]

Re: Can exhaust Gaskets be replaced while in water

most of the exhaust can be removed in the water. Manifolds and riser should be OK but once removed do not over load the boat or leave it in rough water where the static water line can be exceeded. Also, if it is leaking watch for water getting into the exhaust chambers of the system and then getting into the engine. Drain the block and manifolds before removing.

 

[Lou C]

Re: Can exhaust Gaskets be replaced while in water

I recently changed a thermostat with the boat in the water, but the thermo housing is above the water line, and I had wood plugs for the line coming from the transom (which enters the boat below the water line so I plugged it for safety). You would want to estimate how high the water line in the Y pipe is, if it is close to the top of the Y I think is may be too risky, since if a passing boat wake backs up into the boat that open exhaust can let a lot of water in fast. How hard would it be for you to pull the boat? I'd probably do that on on land!

 

[Pst76]

Re: Can exhaust Gaskets be replaced while in water

Thanks for the responses. May be safer to pull up onto trailer. Not worth the risk. I wondered about water in the ports as well ones bolts are loosened.

 

[rbezdon]

Re: Can exhaust Gaskets be replaced while in water

you should have a valve for the block to drain and some type of drain for the manifolds too. Do this BEFORE removing any of the mounting bolts. If it is easy to pull the boat, its a no brainer. Also, then if you find some other issues to be repaired you dont have the issue of the boat stuck in the water and no way to drive it to the boat ramp. This is why I almost always pull my boat to work on it. I bet even some of the more experienced guys have either done some thing stupid of found something you don't expect and need to do more work than planned. If the boat is in the water how do you get it to the boat ramp once it is dismanteled. It is much easier to drive it over there now and pull it just in case. If it is easy you loose nothing. If it is a big problem or you dont have a trailer then it can be done.

 

[lowshovel1]

Re: Can exhaust Gaskets be replaced while in water

Ron, I did exactly that at the end of last season. like a fool I pulled the heads inlate october thinking we would'nt get a hard freeze for another few weeks. the next 2 days 28* for a high.Ended up paying marina to tow it 200' to put it on trailer at ramp.60 bucks. live and learn

 

[rbezdon]

Re: Can exhaust Gaskets be replaced while in water

yup, lots of work can be done in the water but the big IF (something goes wrong) can really get you. I always feel better safe that sorry. BEtter to pull the boat out before major work. I hope FreebeeTony doesnt have this problem and is back running even if it is not at 100%.

 

[Pst76]

Re: Can exhaust Gaskets be replaced while in water

Thanks for the input guys, Boat will be pulled out over the weekend for fix. Not worth the IF's. With my luck the a yacht the size of the Queen Mary would make its way through the Marina with a 10 ft wake.