I just poured the first oil I pumped out of the sump into a clear container into the gallon jug with the rest of the oil. Eyeballing the two, I had expected to come up with more than a gallon but the total amount came to almost exactly what I normally get when I do an oil change, a gallon less what stays in the filter and sticks to the engine parts.
Where did the oil go?
New theory:
I've got some sludge or something in the bottom of my sump. We know that my engine tends to pump oil up the dipstick tube, thus the "O" ring and my scare in the Chesapeake. I ran hard the day before discovering the high oil level because of thunderstorms on the radar. Perhaps the oil level was raised in the rather narrow dipstick tube (a tube with a bend that goes all the way to the bottom of the sump) and the sludge or whatever got pushed in hard enough to keep the level high.
This theory would be consistent with the lack of any fuel smell although the new low sulfur stuff is so clean I think the lube oil could mask it.
This theory doesn't explain the easy initial pumping or apparent low viscosity of the oil. The latter is subjective however. Sludge actually might explain the easy pumping. Perhaps I've always been trying to suck out oil through some sort of debris that partially blocks the thin suction tube I use and that has gotten dislodged.
I've put the fuel system back together with the mechanical lift pump disconnected and just serving as a cover plate. (I'll make one in due course) I've pressurized the fuel system to 6 psi and will look at the gauge in a few hours. I haven't put any oil back in and will also do another dipstick pump to see if anything shows up.
I'm hoping mightily for the embarrassment of this being another of my famous false alarms. I checked the dipstick about four times as it's hard to read so I'm pretty confident about the high reading though.
Wait wait.... Theory Number Two:
I haven't been able to run at WOT because the replacement prop that was put on in the Chesapeake was over pitched. I had the pitch reduced while the boat was out of the water. In addition to running hard because of the weather, I also did some full power running to check the prop and exercise the engine. There was probably more than the usual amount of condensation in the crankcasel because of the short runs in the days before the haul out. Perhaps some of that condensation emulsion got into the crankcase breather hose leaving the crankcase slightly pressurized on shutdown. That could easily have raised the oil level in the dipstick tube the 3/4" I saw.
I'm going to put the oil back in the engine, check the oil levels very carefully, and do a good long hard run before worrying about this any more. If the oil level does rise, I'll pull the crankcase breather line off to be sure the case is depressurized and then measure again.
Who said powerboating was boring?
Where did the oil go?
New theory:
I've got some sludge or something in the bottom of my sump. We know that my engine tends to pump oil up the dipstick tube, thus the "O" ring and my scare in the Chesapeake. I ran hard the day before discovering the high oil level because of thunderstorms on the radar. Perhaps the oil level was raised in the rather narrow dipstick tube (a tube with a bend that goes all the way to the bottom of the sump) and the sludge or whatever got pushed in hard enough to keep the level high.
This theory would be consistent with the lack of any fuel smell although the new low sulfur stuff is so clean I think the lube oil could mask it.
This theory doesn't explain the easy initial pumping or apparent low viscosity of the oil. The latter is subjective however. Sludge actually might explain the easy pumping. Perhaps I've always been trying to suck out oil through some sort of debris that partially blocks the thin suction tube I use and that has gotten dislodged.
I've put the fuel system back together with the mechanical lift pump disconnected and just serving as a cover plate. (I'll make one in due course) I've pressurized the fuel system to 6 psi and will look at the gauge in a few hours. I haven't put any oil back in and will also do another dipstick pump to see if anything shows up.
I'm hoping mightily for the embarrassment of this being another of my famous false alarms. I checked the dipstick about four times as it's hard to read so I'm pretty confident about the high reading though.
Wait wait.... Theory Number Two:
I haven't been able to run at WOT because the replacement prop that was put on in the Chesapeake was over pitched. I had the pitch reduced while the boat was out of the water. In addition to running hard because of the weather, I also did some full power running to check the prop and exercise the engine. There was probably more than the usual amount of condensation in the crankcasel because of the short runs in the days before the haul out. Perhaps some of that condensation emulsion got into the crankcase breather hose leaving the crankcase slightly pressurized on shutdown. That could easily have raised the oil level in the dipstick tube the 3/4" I saw.
I'm going to put the oil back in the engine, check the oil levels very carefully, and do a good long hard run before worrying about this any more. If the oil level does rise, I'll pull the crankcase breather line off to be sure the case is depressurized and then measure again.
Who said powerboating was boring?
