3gm30 running warm and white smoke

[Ereiss]

Thank you, Freedom team.

[GeoffSchultz]

I think one of the main questions is: Is the problem that you're seeing 1 or 2 problems? Did the high temperature cause you to see the smoke (or visa versa) and are they related? I agree with George that finding the cause of the overheating is clearly a first step and hopefully will clear up the problem. However, if you're seeing white smoke when it's cool and it continues even when it's hot, the two wouldn't seem to be a common problem.

-- Geoff

[JimD]

I've always had a problem with over heating with both a 3gm30f and a 3ym30 when the sea water and air temperaturwe are both high. When it's overheating usually see white smoke/steam. I think I've solved that with a 4' exhaust fan in the engine compartment, still runs hotter (150 F) than I'd like it but the engine hasn't over heated since.

Jim Demerest
F36/38
Lady of Remes

[THATBOATGUY]

Something just occurred to me. How are they testing the engine? If they are running it up in gear tied to the dock then they are overloading it and I would expect most engines to overheat under those circumstances.

George

[Michel]

I concur with George; I worried myself sick for months after an overheating problem which I fixed and test running the Perkins 4.108 at 2500 revs tied in the slip. It kept on overheating. We had white smoke in our venerable Volvo 850 car a few months ago and it was definitely the head gasket blown. But that engine did not run hot as long as there was enough cooling liquid.

[Ereiss]

Yard says they fixed it. The fix included:

1. descaling the heat exchanger
2. replacing the very long exhaust hose
3. replacing the water pump
4. replacing the circulating pump (I didn't know I had two pumps)
5. replacing the air intake filter.

Engine runs cool and no smoke. The boat hadn't received much TLC in its life so I'm having the pleasure ($$$) of getting it back in to shape.

By the way, I did see that on cruisersform.com there is someone selling a 3gm30 with 20 hours on it for $2,500. Too late for me now that I've invested as much as I have on my 15 year old engine.

Thank you all for your help.