View Full Version : US Marine 305more steam coming from the exhaust

07-22-2001, 06:19 PM
" I have twin US Marine 305's and both are running great, except the last two weeks I noticed more steam coming from the port engine. Significantly more. There has always been some steam from both, but not what I would consider a lot. The engines both have closed cooling systems. The port engine is not running any hotter than the starboard and the steam does not smell of anti-freeze (what I would then consider a head gasket). Is there a gasket in the risers or the raw water system that may have gone and additional water is mixing with the exhaust? Any other ideas or ways I can find out if it is a head gasket? Any help would be appreciated.

Mike "

Gil Plumb
07-23-2001, 07:57 PM
" Check the exhaust riser where your raw water enters the exhaust system. If the manifolds are raw water cooled you might have a scale build up.
Are you loosing fresh water in the expansion tank? Pressure test your fresh water system with a standard radiator test kit.

Good luck.

Gil "