2000 21i - Exhaust Leak ?

[Dynom8]

I have a 2000 21i and while riding recently, I noticed a very small leak in one of the exhaust pipes extending down after the exhaust elbow. My boat has the MerCruiser 350 MAG MPI Tournament Ski edition engine. I have attached a part diagram to this post...the actual leak is in the lower bend of part 13. Like I say, the leak is very small - I have only noticed a slight trickle of water coming out of the pipe, and when I placed my finger over the leak, I could feel a small amount of air coming out of the pipe.

The actual pipe appears to be made of fiberglass and I am wondering if any of you have experienced a similar problem, and if so what means did you take to fix it? My two choices appear to be either buying a new pipe, which as priced on the Mercury Parts Express website is $357, or using some type of compound/fiberglass sealant to seal the leak. I'm thinking that the latter option is best, if in fact it will take care of the leak. At this point, I don't want to put $600 plus including labor to fix a small leak when I could spend $10 on a tube sealant and patch the leak myself, thereby serving the same purpose as replacing the pipe. Please let me know if you have had the same problem.

Thanks,

- Jason

[CP3]

I would deffinately try to patch the pipe first. Its not a pipe that will get that hot bc it has water running through it.
Its worth a try because if it doesnt work you need a new one anyway

[zad0030]

Had the same problem on both my pipes, and they were pretty good size leaks. I used a two part epoxy. It was rated for temperatures up 250*F and for use on fiberglass. Got that at The Home Depot for about 5 bucks. Make sure you slather it on there pretty good, and let it set before you run the engine.

[spharis]

RTV silicon will win.

BTW when you reinstall, make sure you tighten the clamps on the back of the riser. That is unless you like turning around to see water spraying out of the bilge pump port like a cooling jet on an outboard.

[Dynom8]

I ended up opting with the clear RTV silicone. It worked like a charm! Put it on last Thursday night, let it set up over the weekend and with a water test yesterday, I verified the leak is completely sealed. Not a DROP of water coming out. Thanks to everyone for all the advice!

[zad0030]

I ended up opting with the clear RTV silicone. It worked like a charm! Put it on last Thursday night, let it set up over the weekend and with a water test yesterday, I verified the leak is completely sealed. Not a DROP of water coming out. Thanks to everyone for all the advice!

Glad you figured something out.