coolant leak

[big-un]

Just bought 1987 Larson with MCM165 4cylinder. Runs well, but there is antifreeze getting into distributor cap. Head gasket?

 

[Scott Danforth]

Welcome aboard

NO. you have the infamous 170 motor. google speedy sleeve mercruiser 170. start reading up on this motor. your going to need all the help you can get as any bad idea on a motor got put into it. its sort of the platypus of motors

your going to be replacing cam seals and adding a speedy sleeve to take care of your coolant / distributor issue.

in the future you will also be looking for an exhaust manifold, converting the alternator and doing a bunch of other updates to try to keep this motor running.

 

[Bt Doctur]

There is no way for AF to enter the dist from the motor. Now if you have AF mixed with the oil thats different.

 

[stonyloam]

Check for antifreeze leaking from the small weep hole on the lower starboard side of the engine waterpump. It may only leak while running. If it is leaking you need new cam seals. Do a search here for 470 cam seals. DO NOT TRY TO PLUG THE HOLE! Lots of guys here have redone them, not too bad of a job. No need to pull the engine.