Crank Rear Oil Seal popped out.
Discussion
Well, I finally got my engine (All Steel Scholar 1.9 K)in the car and gave it a shakedown yesterday afternoon. I got 26 miles before disaster, when the rear oil seal popped out, spraying oil everywhere.
The test involved use of 9000rpm. Engine is only 300 miles old so I doubt it has blowby on the rings. Oil scavenge appears to work fine.
So I Google and find this on the old Hellier website:
Crankshaft Rear Oil Seals
These have been known to blow out at high revs due to crankcase pressure, (quite common on various race engines).
Easily cured by ensuring engine is well vented and retaining the rear seal with 2 M3 cap heads.
So a few questions:
Has anyone else had this problem?
My engine venting is from the two outlets on the cam cover - one to an unsealed catch tank, the other to the top of the conning tower on the DS bellhousing. Is this considered adequate or are there other ways of doing this more effectively?
Has anyone tried securing the seal with M3 screws as hellier suggest,or would I be better securing the seal with an oil resisting adhesive sealant a better way? (the stuff used to hold the rear bearing in a Vauxhall XE is ideal here - like Sikaflex 22, but can wiothstand prolonged oil contact)
Thanks
The test involved use of 9000rpm. Engine is only 300 miles old so I doubt it has blowby on the rings. Oil scavenge appears to work fine.
So I Google and find this on the old Hellier website:
Crankshaft Rear Oil Seals
These have been known to blow out at high revs due to crankcase pressure, (quite common on various race engines).
Easily cured by ensuring engine is well vented and retaining the rear seal with 2 M3 cap heads.
So a few questions:
Has anyone else had this problem?
My engine venting is from the two outlets on the cam cover - one to an unsealed catch tank, the other to the top of the conning tower on the DS bellhousing. Is this considered adequate or are there other ways of doing this more effectively?
Has anyone tried securing the seal with M3 screws as hellier suggest,or would I be better securing the seal with an oil resisting adhesive sealant a better way? (the stuff used to hold the rear bearing in a Vauxhall XE is ideal here - like Sikaflex 22, but can wiothstand prolonged oil contact)
Thanks
Edited by TeflonTurd on Monday 28th April 08:15
My dry sumped K running the standard gold pump set up wasn't vented from the cam cover at all , both those outlets were plugged , so was the redundant dip stick position . The dry sump conning tower was vented though and could on occasions blow out quite a bit of oil into the catch tank , especially if well filled and used at higher revs .
Iv Got an MG ZR 160 race car although never had problems with the rear crank oil seal we have done exactly what you have done.
Im having another issue with the front crank oil seal though, that is leaking / blown out under high RPM. We have upgraded the breathers on the top to 10mm holes going to catch tank.
we do not think it is blowby or crank pressure, the crank does not look scored on the end and we have replaced the pump and gone through 4 oil seals.
Has anyone else had this problem?
as getting fired of the track at 110mph is getting quite tiresome!
Im having another issue with the front crank oil seal though, that is leaking / blown out under high RPM. We have upgraded the breathers on the top to 10mm holes going to catch tank.
we do not think it is blowby or crank pressure, the crank does not look scored on the end and we have replaced the pump and gone through 4 oil seals.
Has anyone else had this problem?
as getting fired of the track at 110mph is getting quite tiresome!
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