Help! Got water and don't know from where

[scott9398]

I need some serious help. I have a 2000 Bayliner with a 4.3. Recently it has developed a major stuttering problem. It starts out great and then after about 10 minutes at cruise speed it starts to miss. The plugs on the even side #2,4,6 had a slight amount of water on them. We pulled the exhaust and could find no signs of serious rust from a crack or any problems with the gaskets. Pulled the head, had it cleaned and magnafluxed, no cracks. They did a valve job and replaced the seals. Put the whole thing back together hoping that not finding anything was good. Took it out today, man did it run great (clean heads and fresh valve job) however true to form 15 minutes later same bad miss. I am at a total loss I cannot located where the water is comming from. Please help! Is there a way to pressure check the exhaust off the motor? By the way the odd side is perfectly dry so this problem must be limited only to the even side. And the water seperator filter and hoses have been replaced.

 

[Flukinicehole]

Re: Help! Got water and don't know from where

Yes any mechanic can pressure test the manifold. Did you seperate the riser from the manifold? If not do this first.

 

[Haut Medoc]

Re: Help! Got water and don't know from where

You have either a bad exhaust riser or manifold or the joint/gasket between them....
Don't waste your time pressure testing them, replace them....
& spare yourself the agony of going through the same thing on the other side, & replace them as well because they are not far behind.....
Welcome to iboats, btw......​

 

[mikeneal]

Re: Help! Got water and don't know from where

I agree with above folks , you have a bad exhaust on that side. Is it a freshwater or salt water boat? If salt water do both sides, exhaust is cheap (well not really , but cheaper then motors and they are just a cost of operation if you boat in the salt)

 

[scott9398]

Re: Help! Got water and don't know from where

Ok now I am really stumped!!! The local mechanic replaced the exhaust manifold, flapper valve and the short hose right off the manifold. After about two hours of run time it is still acting up. Can anyone explain to me how in the f@%k there could be water killing the plugs after all that has been replaced. I have reached the end of my patience. At this point every thing outisde the short block has either been replaced or rebuilt. Does anyone know how to perform and exorcism on a boat because mine sure as hell is telling me to "GET OUT "

 

[180shabah]

Re: Help! Got water and don't know from where

The local mechanic replaced the exhaust manifold, flapper valve and the short hose right off the manifold.

Did he replace the riser/elbow?

Did he verify the mating surfaces of the manifold riser joint were flat?

 

[scott9398]

Re: Help! Got water and don't know from where

The manifolds on my boat are one piece, no additional riser used. I wonder could an ignition problem cause water to be sucked back into the manifold killing the other 2 cylinders?