Reply To: 1972 Evinrude Lightwin 4hp

[Don]

A fine coating of sealer won’t hurt anything, unless it is overdone and gets into the reeds holding them open.  You have the two different intake gaskets oriented properly so there is not air leak between the crankcases.  Your buddy mentioned the engine runs “hot”, any evidence of overheat?  When was the last time the engine ran?  This engine has many small cooling passages that are easily plugged by salt water.  Was the carb dirty/fouled when you cleaned it?  Are you sure nothing is blocking that idle passage that runs up through the side of the bowl into the upper carb body?  The engine runs on starting fluid, but won’t run on its own, correct?  What happens when you just squirt fuel/oil mix in the carb throat, will it fire briefly then?  Perhaps your fuel supply is old, or contaminated with some water.  Once things start getting too complex, I always back up and recheck the simple stuff.  Nine out of ten problems are relatively simple ones, that we complicate by looking for more serious issues.

The only other thing I can think of is perhaps the head gasket is blown from overheating, although your compression readings seem normal and even….