Completed the compression test on my '85 merc 260
10-25-2004, 09:14 PM
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Re: Completed the compression test on my '85 merc 260
So would that mean I am looking at a rebuild if that's what the leak down test showed? thx
Jim
Jim
Last edited by JGB; 10-25-2004 at 09:17 PM.
10-25-2004, 11:17 PM
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Re: Completed the compression test on my '85 merc 260
Proof is in the leakdown test,i did my motor a few wks ago and my weakest cyl had 120 psi crank compression (after 10 cycles),80% leakdown!!!,best cyl had 10 % leakdown and was bumping 160 psi after 4 cycles of motor. Funny thing was boat ran ok,was 1/2 mph off normal speed and didn't have much blowby. When you did your compressioin test did the lower press cylinders take more turns/cycles of the motor to get to there max? If they did it is definately weak,leakdown test,post your results,Smitty
10-26-2004, 01:04 AM
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Re: Completed the compression test on my '85 merc 260
Originally Posted by JGB
was told engine had 40 hours on a rebuild. certainly can't belive that.
Jim
Jim
Michael
10-26-2004, 08:57 AM
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Re: Completed the compression test on my '85 merc 260
the blow by seen is a alot. there are 2 mr gasket breathers on the valve covers(one on each side. When I slow down to idle after a run and open the engine hatch it looks like a smokehouse.
Carb was rebuilt twice because after the first rebuilt it started flooding the engine after 10 min of run time.
The motor has a mild aftermarket cam which I thought it should be running higher than 4500 rpm.
Carb was rebuilt twice because after the first rebuilt it started flooding the engine after 10 min of run time.
The motor has a mild aftermarket cam which I thought it should be running higher than 4500 rpm.
