1972 55hp chrysler

[jdman]

the compression reads 160 and 170 on this motor. this seems awful high to me. could this be an indicator of excessive carbon buildup? if so, can it be removed without taking the head off? also, could this explain a ruogh idle, with one cylinder firing sporadically? thanks jdman

 

[OBJ]

Re: 1972 55hp chrysler

Hey jd....<br /><br />A Chrysler with that kind of compression? I'd be praying to the God of Outboards for my good fortune. Seriously, you don't have to remove the heads to decarb. There are several products with names like "Tune Up" that will help. Check the iboats store or visit your local dealership for directions. Their use is simple. Just run the engine up till operating temp and squirt the tuner into the carbs. Follow directions on the can. Your rough idle could be simple as a spark plug. Points could also need a change out or a possibly a coil going south.