I recently took ownership of a 26' Grady White with 2 identical Mercruiser 3.0 140 HP 4 bangers. The boat was in terrible shape and I spent most of May and June in the driveway piecing things back together. Eventually I got her running, timed and cleaned up. I noticed steam coming out of the starboard engine breather vent hose, which as part of the flame arrestor on this boat goes right up onto a bracket over the air cleaner. I didn't find any symptoms of a compromised water jacket though, oil looked fine, oil level was consistent. I assume water had gotten in during the 4 years she sat in humid S Carolina. I changed the oil a few times and sure enough it stopped.
Then, I put in the water and started using her to fish, after a few issues with fuel flow (previous owner had installed new tanks but no 'plumbing' and not until I got two vents and two filters and completely separated everything between the two engines would she perform poorly at full speed) she behaved very well.
But then steam problem showed up in the port engine. I assumed the issue was the same, since there is no evidence of a compromise between the oil and water systems in this engine either. The risers are cool to the touch when she's a full throttle, and the oil isn't milky, oil levels are consistent. But by now any oil condensation I have to assume would have boiled off. I know these engines are susceptible to freeze and crack inside which would allow oil and water to mix, but I just don't see how it could be that, extracted motor oil looks relatively clean. Certainly not 'milky' as I was told it would be if this was the issue.
Also, there was lots of water damage back there and more on the port side. For example, the trim pump motor didn't work, I bought a replacement but took the old one apart for fun and it was FULL of water. I don't think this boat sank, but I think previous owner had some waves break over the stern at some point.
One small difference between port and starboard, starboard has a tube attacked to the oil pan drain so I could really empty the old oil (and water) out, port does not; I have to use a pump and those never really get it all, do they.
So I have steam blowing out of the breather hole on the valve cover, do I have a cracked engine, condensation, something else? How to tell? I have disconnected the hose from the air cleaner bracket to avoid blowing water and oil into the carb; the steam seems to blow out oil as well. Not much a couple tablespoons worth after a 25 minute burn at 4500 RPM. Engine performs very well otherwise, good power, easy starts, no stalls, etc...
Thanks in advance,
drGian
Then, I put in the water and started using her to fish, after a few issues with fuel flow (previous owner had installed new tanks but no 'plumbing' and not until I got two vents and two filters and completely separated everything between the two engines would she perform poorly at full speed) she behaved very well.
But then steam problem showed up in the port engine. I assumed the issue was the same, since there is no evidence of a compromise between the oil and water systems in this engine either. The risers are cool to the touch when she's a full throttle, and the oil isn't milky, oil levels are consistent. But by now any oil condensation I have to assume would have boiled off. I know these engines are susceptible to freeze and crack inside which would allow oil and water to mix, but I just don't see how it could be that, extracted motor oil looks relatively clean. Certainly not 'milky' as I was told it would be if this was the issue.
Also, there was lots of water damage back there and more on the port side. For example, the trim pump motor didn't work, I bought a replacement but took the old one apart for fun and it was FULL of water. I don't think this boat sank, but I think previous owner had some waves break over the stern at some point.
One small difference between port and starboard, starboard has a tube attacked to the oil pan drain so I could really empty the old oil (and water) out, port does not; I have to use a pump and those never really get it all, do they.
So I have steam blowing out of the breather hole on the valve cover, do I have a cracked engine, condensation, something else? How to tell? I have disconnected the hose from the air cleaner bracket to avoid blowing water and oil into the carb; the steam seems to blow out oil as well. Not much a couple tablespoons worth after a 25 minute burn at 4500 RPM. Engine performs very well otherwise, good power, easy starts, no stalls, etc...
Thanks in advance,
drGian
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