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OMC stringer vs cobra exhaust manifolds

weterthebetter

weterthebetter

Member
I just ran water to the hose inlet and stuck a rag in the 3.5 out let and water was pouring into my exhaust ports.
This is on a 1985 4.3 omc stringer,
Looking in EBAY are are some listed as OMC Cobra that have the same manifold castings as my stringer

Port 984221
starboard 984222

will the gray cobra manifolds fit my stringer?
the casting numbers are the same as my silver stringer manifolds
thank you
 
Ayuh,.... The Stringer uses 2 piece manifolds, 'n risers,....

Those early Cobra manifolds, If the 1 piece units, without a gasketed joint 'tween the manifold, 'n risers, as I've said, are a Known Failure, because of core-shift durin' the castin' process,....
And,...
The 1 pc batwings won't line up with the exhaust ports of the stringer drive,....
 
bondo said:
Ayuh,.... The Stringer uses 2 piece manifolds, 'n risers,....

Those early Cobra manifolds, If the 1 piece units, without a gasketed joint 'tween the manifold, 'n risers, as I've said, are a Known Failure, because of core-shift durin' the castin' process,....
And,...
The 1 pc batwings won't line up with the exhaust ports of the stringer drive,....
Click to expand...

Batwings is what is on the 1985 stinger engine now, Port 984221 starboard 984222
I found A set of batwings the set for $ 350. from a local boat repair shop.
They have a set a batwings with castings numbers the same as my old ones so they should fit ,RIGHT??????
All that matters is they are not cracked now, I'm selling the boat
Monday I'm going to test the new set by putting water into the hose inlet and jam a rag in the outlet ,
to check for internal leaks to the ports.
Id rather sell this boat in good running condition than selling it knowing there is a problem.,
I'm just glad the block is not cracked.
Thanks again for all your help.
 
Here is the area near the top where those Batwings are leaking into the exhaust ports.
I set the manifolds up right like it is mounted to the engine and put a hose on the inlet , higher than the out let.
The acetone and water did the same thing , as the liquid got to the out let it started to pour in to the exhaust ports


Batwing Manifold.jpg
 
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I will have to do the test all over. With the
hose's connected to the out let I did not see the
2 or 3 or more little ports when the water mixes with the exhaust stream,
after the downturn, but before the actual exhaust outlet,....
I did not know what Bondo was talking about till I took off the 31/2" hose from out let.
 
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Ayuh,.... The water discharge ports are visible on the manifold on the right, in yer picture,....
 
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