bad manifold or riser problem?

slider101

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Could anyone tell me the symptoms of a bad manifold or riser or elbow? I have a 1983 citation open bow with 2.5l chevy omc i/o. I can idle fine in water but when i put in gear and accelerate engine bogs down severly and sometimes stops. My manifold and riser and elbow look very bad and deteriated. I also did a head gasket replacement cause i was getting water in oil. Engine doesnt seem to have a crack. Can these bad items cause these symptoms and water get back into oil if it is getting past seals from rot? Thank you.
 

Bondo

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Re: bad manifold or riser problem?

Could anyone tell me the symptoms of a bad manifold or riser or elbow? I have a 1983 citation open bow with 2.5l chevy omc i/o. I can idle fine in water but when i put in gear and accelerate engine bogs down severly and sometimes stops. My manifold and riser and elbow look very bad and deteriated. I also did a head gasket replacement cause i was getting water in oil. Engine doesnt seem to have a crack. Can these bad items cause these symptoms and water get back into oil if it is getting past seals from rot? Thank you.

Ayuh,... The manifold, 'n riser usually go Bad, where they meet at the gasket face...
If it leaks, it drop water into the exhaust cavity...

Yer symptoms sounds like a Bad carb, or a general fuel delivery issue...
 

slider101

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Re: bad manifold or riser problem?

Ayuh,... The manifold, 'n riser usually go Bad, where they meet at the gasket face...
If it leaks, it drop water into the exhaust cavity...

Yer symptoms sounds like a Bad carb, or a general fuel delivery issue...

To further explain my problem, when on land and muffs i can accelrate through full rpm when in gear, put it in the water and idles fine but shuft into gear and accelerate and it bogs down and dies. Still sound like a carb or fuel problem to you?
 

Howard Sterndrive

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Re: bad manifold or riser problem?

definitely sounds fuel related. On land, you can fuel your engine to 5000 rpm with an eye dropper.
Under load, on plane, you need a garden hose-ish fuel flow.

but, with your cosmetically challenged manifold, you can simply pull the spark plugs after running it and look for water on the plugs as an indication of failing exhaust.
 

slider101

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Re: bad manifold or riser problem?

Im just tired of making trips to the lake to test underload! Maybe i can find something to submerge the sterndrive in on land to put a load on the prop.
 

Bondo

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Re: bad manifold or riser problem?

Im just tired of making trips to the lake to test underload! Maybe i can find something to submerge the sterndrive in on land to put a load on the prop.

Nope,.... It Don't work that way....

It ain't 'bout havin' the prop in water,...
It's 'bout the prop Pushin' the hull, Under Load....
 

Borchik

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Re: bad manifold or riser problem?

I would agree on the fuel issue, plugged filter, sucking air at a fitting or line, something like that.
 

slider101

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Re: bad manifold or riser problem?

I will check fuel issue then, thanks. But water in my oil could be associates with a bad riser and manifold though as long as my oil level isnt rising real high and just slightlymilky right? If it is leakin on the intake side and gettin on top of the pistons? If that is the case and the plugs have moisture couldnt that cause it to exhibit similar symptoms and bog the engine down by putting water in the combustion chamber? If it is a small leak and idles fine but when you get on ut and really pumping water through the engine? Just a thought but i will definitly rebuild the carb and check fuel pressure and delivery system.
 

Bondo

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Re: bad manifold or riser problem?

If it is a small leak and idles fine but when you get on ut and really pumping water through the engine?

Nope....
 
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