I'm working on a "new to me" 2001 Merc 15 four stroke. It seems to have oil pressure issues.
Symptoms:
Checked these already:
Not really sure where to go from here. I've heard there is an over pressure oil bypass value inside the case, but I can't find it. There also seems to be a case/leg gasket that seals a pressurized oil gallery. Wonder if that may have blown a hole into it.
It has been guested to attach an oil pressure gauge to measure the level. But I'm not sure how that's going to help. The oil pressure is so low the engine won't run properly. So why worry about measure how low is low.
I'm attaching photos of a block. Maybe someone can point out the oil bypass valve. I think it might be my next thing to check.
Other ideas?
Symptoms:
- Runs fine from cold for about 30sec then oil pressure drops and oil pressure warning (ignition system goes into limp mode too)
- Idles fine
- Crank case seems to have a lot of blow by air pressure, doesn't blow out dipstick or anything (Not sure what's "normal" on these, I've heard everything from nothing --> there can be a fair bit)
- No exhaust oil smoke
- With oil filter removed, I can turn over the motor and oil pumps into the filter area.
Checked these already:
- New oil and filter today (10-30 conventional)
- Oil level @70% on the stick
- New oil pressure sensor
- Water thermostat opens properly at 60C
- Disconnect oil pressure switch from ignition module and runs normally
Not really sure where to go from here. I've heard there is an over pressure oil bypass value inside the case, but I can't find it. There also seems to be a case/leg gasket that seals a pressurized oil gallery. Wonder if that may have blown a hole into it.
It has been guested to attach an oil pressure gauge to measure the level. But I'm not sure how that's going to help. The oil pressure is so low the engine won't run properly. So why worry about measure how low is low.
I'm attaching photos of a block. Maybe someone can point out the oil bypass valve. I think it might be my next thing to check.
Other ideas?
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