leaking exhause pipe to outdrive

[ebizsearch]

After months of restoring a 1985 23ft.aftcabin wellcraft that was said to have newly rebuilt 260-270 HP (i think) 350 Mercruiser engine, I have a huge leaking problem with the boat. After launching it water was coming in at the bottom of the transom under the inside out-drive mounting plate. Marina attendant said it was a leaking exhaust pipe from manifold to inside out-drive mounting plate.
He also stated that the engine would have to be removed to replace it. Can anyone confirm this? After putting boat on trailer we filled bulge with water and it came out of a hole on the lower right side of outer transom mounting bracket.
No water came out of the left side. This is big trouble with big $. I think I have been had although the engine has new manifolds, elbows, rubber hose & s/s clamps. Can anyone help.

 

[Bondo]

Re: leaking exhause pipe to outdrive

He also stated that the engine would have to be removed to replace it.

Ayuh,.... That is Correct,....

Which hole on the starboardside was leaking,..??

 

[boatguya1]

Re: leaking exhause pipe to outdrive

If you're going to pull the motor to seal up the y-pipe. (exhaust in question by your description) Do a transom seal while you are there, it's 24 years old and you don't want to be pulling the motor again in 6mos to do it.

Most shops won't pull the y-pipe during a motor rbld. Especially if it's a customer who wants to tell you exactly what to do and is tight with the $$.

James

 

[Bondo]

Re: leaking exhause pipe to outdrive

And of course,... If it's the transom seal that's leaking,+ Not the Y-pipe,...

That means the Transom is Rotten, as transom seals don't tend to just start Leaking for no reasons at all....

 

[ebizsearch]

Re: leaking exhause pipe to outdrive

There are holes on each side of the outer transom mounting plate (gimbal i think you call it). Located just under the exhaust bellow but off to each side. Also just above the two lower mounting fasteners on each side.

If it could a leaking mounting bracket seal, would it be wise to remove the outer drive and bracket before removing engine to replace seal and inspect transom condition?

 

[boatguya1]

Re: leaking exhause pipe to outdrive

The engine must come out to check the transom hsg seal/ remove outer bracket. You must also remove the exhaust y-pipe to look there.

James

 

[270 Angler]

Re: leaking exhause pipe to outdrive

I just went through the very same problem that you're having with the leak. It was the Y-pipe on mine that was bad. It was missing the bottom two bolts. Saltwater ate the ears off the y-pipe. Pulling the engine wasn't as bad as it sounded and it gives you peace of mind to check the seal on the back gimble housing and replace it while you have the engine out. The seal was only $6.00 and i bought a used freshwater y-pipe for $120.00. Mine is a omc cobra. Good luck and it's not as bad as it seems

 

[proshadetree]

Re: leaking exhause pipe to outdrive

Same thing happened to me.I had just put engine in to.Didnt check pipe.When I went back in I wanted to check all.I had rot in my transom.
Not real bad but once I got to cutting it out it was horrid.Took a weekend to fix.Not that bad a job compared to pulling a fount drive car.

 

[ebizsearch]

Re: leaking exhause pipe to outdrive

Thank all for the comebacks. I guess I will be pulling the engine & stern drive now. Does anyone know what the "Y" exhaust pipe is made of? How did it last so long in salt water. Is it stainless steel & is it repairable? Anyway, My problem is my boat is a wellcraft aft cabin on a trailer with the rear gunnel about 6 feet from ground. I got to have a hoist at least 10 to 12 feet high. Anyone in Richmond, Va. with nothing to do and want to play boat repair with me.

 

[ebizsearch]

Re: leaking exhause pipe to outdrive

Getting ready to remove engine. Have removed outer drive unit. Having problems obtaining replacement exhaust Y pipe. Do not have model or ser. # of engine. All data was remover and not replace during 1999 rebuild. I guess it is a 1985 350 CID chev. engine w/ bbl carburetor. I am guessing it is a 260-270 HP. Enyway I have two or more part numbers of y pipe. one is 807130 the other is 99877 and prices from $275 to $790. Anyone know how do I find correct part.Can I just wait to remove old part and try to match the part, which will be difficult on a
the internet.

 

[littlebookworm]

Re: leaking exhause pipe to outdrive

Before you go through pulling the engine out of the boat, take a look at the room in front of the engine itself. Can you slide the engine forward about 6"? If you can, you can change the Y-pipe and anything else you need without lifting the engine. I was able to do this on my Sunrunner. I laid a 6" x 6" post across the sides of the boat, used a come-along to lift the rear slightly, and used a 6' prybar and then a length of 2" x 4" to slide the engine forword. I put some lumber cribbing under the rear of the oil pan to keep the engine up, and then removed the beam and come-along. I had plenty of room to pull the Y-pipe and then the transom mount (which I had broken, neccesitating the whole job). Pushing the engine back oin place was just a reversal of operation. Remember to change the double wound lock washers on the rear mount while you're at if (assuming your engine has them). Realign the engine after you finish with the repair/replacement. Check a manual for more details.Good luck. Hy

 

[ebizsearch]

Re: leaking exhause pipe to outdrive

Ha, Thanks for the information. This looks a lot better. I have about 6" forward
to the gas tank location. How did you Realign the engine.
thanks for the help.

 

[Gary H NC]

Re: leaking exhause pipe to outdrive

You will need an alignment bar that slides into the coupler from the transom..
Maybe your local marina will loan you one or you can find them on Ebay for about 50 bucks..