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MGB Weird oil question

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Rut

Rut

Obi Wan
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I'm baffled (no stranger to that) about my oil level on the dipstick. I have a rebuilt 18v, 9.5 compression, VP12 cam, AL flywheel, single aluminum side plate venting into carbs...nothing outrageous. The car runs like a scalded dog and easily pulls to redline and has no obvious issues until today. After a short 20 minute drive the car was at normal temp, 70 psi op and running great. I park in my level driveway and pop the bonnet in preparation for a general check including oil level. I finally get around to checking it 30 to 40 minutes later after it had cooled a bit and the oil level was just below the add oil mark...not unusual since it goes to the low mark every time I drive it (dip stick may not be correct, others have lower marks). This typically means about 1/2 qt of oil which I added. After about 10 minutes I checked the oil again and it's half again over the full mark! 1/2 GT of oil can NOT make that much of a change! Thoughts?
Thanks, Rut
 
There's some oil that is still draining back from the lifter valley and the cylinder head. Those, along with oil dripping back from other internal parts, could be 1/2 qt.
 
Jack,
i don't think I've ever seen it take more than 30 minutes for all the oil to drain from the head and tappets...even the oil cooler. Is there some kind of 'air lock' that could prevent the oil from returning until I open the oil filler cap to add oil? I'm due for an oil and filter change in a couple of hundred miles and I'll investigate more...this is too weird.
Thanks, Rut
 
Offhand, sounds like you "burning" 1/4 qt each time. Instead of adding 1/2 qt as usual, try 1/4 and see how that goes
 
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