Marinette Boat Forum

I have an exhaust leak that I'm unable to find (I just took a quick look while both motors were running). Does anyone have any tricks to help find the problem spot?

Merry Christmas,

Water in the bilge or smoke?

I'll bet you a steak dinner it's leaking from the intake manifold, in the center (where the choke heater circuit is). The intake gaskets MUST use these little metal plates to seal that area off or it WILL leak.

Here's what the deal looks like,

Jeff

Whoops! Try again.

Jeff

Smoke... No water. If I drop a few drops of oil in the air intake would it put some smoke out of the leak?

An exhaust leak here does not produce a water leak.

Jeff

My Exhaust leak did produce water. My Muffler was leaking at the seam. I think the boat yard didn't fully winterize and it split.
After I realized therre was no way to get the muffler out without dismantling the entire exhaust sistem I simply encased the muffler in fiberglass as that is what it is made of and that was it.

Haven't had a problem in 12 years


Commander Matt

If you are getting smoke in your bilge, I would suspect (unless your engine runs rich) that you have a valve cover leaking oil onto the un-cooled section of the exhaust manifold. I have seen this on a lot of engines that no longer have the factory valve cover bolts in them. Especially the chrysler because of how much exposed, non jacketed exhaust port there is.

That might also be it. I had to retighten the valve cover bolts on mine (after the motor was together for 8 years).

Jeff

Check the end plate in the manifold. They rust out. If so be careful getting the bolts out lots of penetrant and heat. They're no fun when they break.