leaking exhaust manifold 4.3 L

[badgerman]

1994 Glastron SSV 195, 4.3 L Vortec, Mercruiser Alpha I. Water pours in off the rear of exhaust manifold, no sign of water up higher. My mechanic said very common to have to replace or tighten the four bolts that hold the two sides together behind engine inside boat, as they loosen and sometimes fall out. Apparently if you wire the nuts on they last forever but to solve this problem motor must come out. I laid in there with mirror, cannot see any bolts, looks like it is one piece, not bolted together, no bolts or nuts laying in the bottom. He claims he's done 24 of them in the past 10 years, no bolts have been wired when he gets in there, but he always does. He is a very good mechanic, but I've searched posts and can't find anyone with that comment. Anyone have a pic they can share so i can be confident before he spends the day pulling the motor? Any other comments?

 

[Bt Doctur]

Re: leaking exhaust manifold 4.3 L

Clarify "off the rear of the manifold". Have new manifolds and risers been installed?
Check page 36 in this link,
http://www.boatfix.com/merc/Install/instlcov.pdf

 

[badgerman]

Re: leaking exhaust manifold 4.3 L

Thanks for the links, looked all over for a pic like that. Sorry used the wrong term, water coming off the bottom of lower exhaust pipe, near where the two sides come together just before exiting the boat. Under "Section 7, Collectors" in the link you attached.

 

[Bt Doctur]

Re: leaking exhaust manifold 4.3 L

Commonly called the Y pipe, I`d think it`s more of a corroded hole thru it than just being loose. I`ve never had one loosen up .You can test it by removing the drive, plugging up the exaust ports and transom housing reliefs ,pull a riser and put water in the Y pipe and see if it leaks into the bilge.

 

[badgerman]

Re: leaking exhaust manifold 4.3 L

I'm not a mechanic as you can tell, first time boat owner. He quoted me 7-8 hrs to remove engine and fix the prob. How much time to remove the drive? Wouldnt motor have to come out anyway assuming i am right about where water coming in? I laid in the bottom of the boat and put my hand on it, pretty sure its somewhere in the Y pipe. Not wet above it. Feels like its just to the starboard side of where the crotch is. When i asked mechanic that question he said never run into corrosion or holes or cracks in his life, most likely bolts. I may also try to put a scope/camera in the drain hole, dont suppose i will see a crack or hole though. If the motor comes out, i will try to be there. The engine was rebuilt 12 hours ago. Nice.

 

[freeone]

Re: leaking exhaust manifold 4.3 L

I'm not a mechanic as you can tell, first time boat owner. He quoted me 7-8 hrs to remove engine and fix the prob. The engine was rebuilt 12 hours ago. Nice.

never mention that to a mechanic. best discription would be i have a leak find it, then get a second opinion. may be a good mechanic but sounds like hes a good hustler too. did he do the rebuilt? do you have a one piece y pipe or 3 piece. i have the 3, there is bolts on the 3. when i replaced my exhaust shutters those bolts werent that easy to come off let alone get loose or fall off.

 

[badgerman]

Re: leaking exhaust manifold 4.3 L

No he didnt do the rebuild. I really dont think he's a hustler, small town, very good rep, but seems funny that no one seems to be jumping out and saying they had the issue too, makes me concerned. Dont know if it is 3 pc or one, I will look into that, and make sure i know what the prob is before the old R&R. Thanks for your time, i appreciate it. Any other advice would be great. I'm thinking outboard, i'm tired of standing on my head.