How dry should a dry sump be?
Posted: Fri Aug 18, 2017 2:06 pm
Spiess pumped XE Dallara. Single stage pressure pump, single stage scavenge back to the oil tank via the oil cooler. Oil tank breathes into catch tank which then breathes to atmosphere. Crankcase breathes to same catch tank from what would have been the dipstick hole in a standard car. There is a baffle plate at the entry to this breather to stop the splashes in the crankcase going straight up the breather. All standard XE Dallara fit so far as I am aware.
Engine rebored with negligible mileage and satisfactory compression so it isn't blow-by pressuring the crankcase.
Immediately after switch off I removed the sump-to-scavenge stage collector pipe and drained approximately 0.8 litre oil out of the sump. The car also seems to be putting a lot oil into the catch-tank - can't make it do it in the garage but after the last test session I found best part of a litre in there. Scavenge pump gone bad because it has had too many bits of engine through it?
Was this the cause of my collapsing oil pressure and oil leak problems last time out because there was more oil in the sump than in the oil tank?
Frustrated and mystified. All offers of advice / help welcome.
Regards
Mark Schofield
Engine rebored with negligible mileage and satisfactory compression so it isn't blow-by pressuring the crankcase.
Immediately after switch off I removed the sump-to-scavenge stage collector pipe and drained approximately 0.8 litre oil out of the sump. The car also seems to be putting a lot oil into the catch-tank - can't make it do it in the garage but after the last test session I found best part of a litre in there. Scavenge pump gone bad because it has had too many bits of engine through it?
Was this the cause of my collapsing oil pressure and oil leak problems last time out because there was more oil in the sump than in the oil tank?
Frustrated and mystified. All offers of advice / help welcome.
Regards
Mark Schofield