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89 Mercury 200 BlackMax EFI

mphinton

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Serial #OC164972

Doesn’t go over 2000 RPMs
Idle is perfect
4 out of 6 cylinders read 119, other 2 either read 0 or 90
Good amount of white smoke

Ideas? Suggestions? Recommendations?
 

Flying_Lavey

Dreaming of the lake
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Serial #OC164972

Doesn’t go over 2000 RPMs
Idle is perfect
4 out of 6 cylinders read 119, other 2 either read 0 or 90
Good amount of white smoke

Ideas? Suggestions? Recommendations?
These motors run totally different when there is a load on them. Idle and running it on a hose gives different results.
 

HST4ME

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Nov 9, 2015
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Motors with 0 and 90 don't idle perfect. First thing you do is pull the head off the one with 0 and see wtf.
 

stingray11

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200 efi was the worst motor they built,they all do it. Find a new motor, 225 were better.
 
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