old kiekhaefer 500 50hp not winding up consistently

[timou812]

I have an older mercury Kiekhaefer 500 50 hp four cylinder SN-1556140 no modifications, new plugs,clean new gas proper mix on 16 ft aluminum starcraft, it does not seem to hit high RPMs or kick into high gear for lack of the proper terms. I had it out for the week on a trip and it seemed to hit high gear 2X only other than that it seemed to be stuck at mid point?

 

[Chinewalker]

Re: old kiekhaefer 500 50hp not winding up consistently

How's the compression? High and even across all four cylinders? Most gauges should read above 100psi on each hole with no more than 5% difference between them.<br /><br />Is a good hot blue spark present on all four plugs (Champion J6Cs or similar)?<br /><br />Are both carbs clean and linked properly? Spraying carb cleaner down the throats won't help - they gotta come apart to clean properly.<br /><br />Check the basics and get back to us...<br />- Scott

 

[paddy87]

Re: old kiekhaefer 500 50hp not winding up consistently

Maybe need a lower pitch prop if yours is pitched at 14 or up