Hi all,
My Mazda 3 1.6 diesel (DV6C). It has always had a bit of oil leak on start up, I have put this down to higher mileage valve stem seals (245000km ~153000miles). There is no noticeable movement on the dip stick and only last for the normal 10-20 sec on start up and then clear as day. There is a throttle but is fully open unless the EGR is engaged and that only happens under low boost condition not under no boost. This mean the only time there is vacuum(less then 12psi or less the atmospheric) is on start up.
My question is that is the stem seal leak oil down into the intake runner when under vacuum then can boost get into the crankcase and pressure the crankcase. Looking up how to make a rig to test crankcase pressure.
My max boost is 22psi normally about 14psi on a gtv1544v. Crankcase pressure should be about 0-6psi but I'm used to petrol so that might be different in diesel land.
My Mazda 3 1.6 diesel (DV6C). It has always had a bit of oil leak on start up, I have put this down to higher mileage valve stem seals (245000km ~153000miles). There is no noticeable movement on the dip stick and only last for the normal 10-20 sec on start up and then clear as day. There is a throttle but is fully open unless the EGR is engaged and that only happens under low boost condition not under no boost. This mean the only time there is vacuum(less then 12psi or less the atmospheric) is on start up.
My question is that is the stem seal leak oil down into the intake runner when under vacuum then can boost get into the crankcase and pressure the crankcase. Looking up how to make a rig to test crankcase pressure.
My max boost is 22psi normally about 14psi on a gtv1544v. Crankcase pressure should be about 0-6psi but I'm used to petrol so that might be different in diesel land.
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