Bertram33 User Forum

After starting the engines (gas mercruiser 454's) I noticed a sheen on top of the water exiting the raw exhaust water. I'm not sure if it's antifreeze or oil. Anyone else have this before, and if so what might be the problem. I replaced both heat exchangers last year. Thanks Mike

Mike, Is it on both sides or just one? I had that once on my Delta and it turned out to be a pin hole in the Port side heat exchanger for the transmission. A pin hole will suck the fluid out without adding water in the early stage. 1979 Bertram 33' FBC ALEXANDRA Port Richey, Florida

I was leaving a sheen last year out my port engine exhaust, it turned out to be the transmission cooler. Check your tranny fluid, if it is milky then that is the problem. Easy, and cheap fix. Good luck! Bill Dunlop "Rebecca Rose" 1988 FBC Ipswich, Massachusetts

it was an oil cooler for me.The best thing to do is take off the cooler and have it pressure tested. Tim Stamm Photo Finish 1981 33' Bertram FBC

Mike, Did you find the cause yet? 1979 Bertram 33' FBC ALEXANDRA Port Richey, Florida

It's either the Transmission oil cooler or the Heat exchanger. I have exactly the same problem. I replaced the Heat exchanger about 1 1/2 yrs ago. I replaced both oil coolers. And now I notice the fluid level dropping in the coolant recovery bottle. Got to be the Heat Exchanger even if it's new. I can't bitch cuz it was free. The guy that owns Sendure is a friend of my neighbor, and he gave me 2 new ones. They can pressure test them, and the guy told me they work fine, if you don't have to seal off more than 2 tubes. Gene Dugan

Yep, it seems like you can always count on it being a cooler. 1979 Bertram 33' FBC ALEXANDRA Port Richey, Florida