Exhaust Leak

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Ryan
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Exhaust Leak

Post by Ryan »

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,
1986 32' Sedan
Chrysler 360's
Cleveland, Ohio
Tranquilo
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Re: Exhaust Leak

Post by Tranquilo »

Water in the bilge or smoke?
2x 1973 28 Express - Single 318
New electrical panels, water system and velvet drive
Miami FL & Catawba OH
Fastjeff
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Re: Exhaust Leak

Post by Fastjeff »

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
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
Fastjeff
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Re: Exhaust Leak

Post by Fastjeff »

AA.JPG
Whoops! Try again.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
Ryan
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Re: Exhaust Leak

Post by Ryan »

Smoke... No water. If I drop a few drops of oil in the air intake would it put some smoke out of the leak?
1986 32' Sedan
Chrysler 360's
Cleveland, Ohio
Fastjeff
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Re: Exhaust Leak

Post by Fastjeff »

An exhaust leak here does not produce a water leak.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
btride72
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Re: Exhaust Leak

Post by btride72 »

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
EWRice
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Re: Exhaust Leak

Post by EWRice »

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.
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1972 32' Express flybridge
"AL13"
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1963 Thompson Super Sea Lancer
Graymarine 327
1961 Alumacraft 12'
'55 10hp Johnson
Fastjeff
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Re: Exhaust Leak

Post by Fastjeff »

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

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
martindesign
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Re: Exhaust Leak

Post by martindesign »

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.
Machanic, fabricator, carpenter, plumber, electrician, designer, hotrod builder and glutton for punishment. :ugeek: current boat; 1969 Marinette 32 express bridge 440's
Catawba Oh
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