mid 80,s evinrude 235hp v6 no low end power

[QSS]

Hi i am new to this website and just wanted to get someone elses advise on a problem i have with a 235hp v6 evinrude outboard i have. its mid 80,s and seems to be labouring under load. once its up on the plane its fine just no low end power. i,ve done a compression test on all cyl,s and have 5 cyl,s at 110-115 and one cyl at 90psi would that be enough to cause the problem. any help or advise would be appreciated. i,ve played with props and changed fuel and plugs but no better.
thanks

 

[freddyray21]

Re: mid 80,s evinrude 235hp v6 no low end power

the low cylinder might be the problem as it it running uneven on all six then. Might be time to take a look at the head on that side for a new gasket.

 

[jonesg]

Re: mid 80,s evinrude 235hp v6 no low end power

25 psi difference low to high is outta spec,
try a seafoam decarb and retest.
it might not be firing on all cylinders.

 

[emdsapmgr]

Re: mid 80,s evinrude 235hp v6 no low end power

Spark check the engine to make sure you have good spark on all 6. Esp when under load-in gear. With that much comression variance, I'd want to have a look at the low cylinder. You can pull the intake side cover or the head on that side and have a look. If the cylinder walls are smooth, decarb it. If you have scuffed pistons (alum transfer to the cylinder walls) you are looking at a tear down. Have you overhauled the carbs lately to be sure all 6 are flowing fuel properly and that there is no debris in any of the jets? If you have arestriction in a carb, it also means you are not getting proper oil to that cyl.

 

[QSS]

Re: mid 80,s evinrude 235hp v6 no low end power

Thanks guys i,l carry out some more tests.