Posted by Greg Coffin [172.68.34.7] on Sunday, April 02, 2017 at 20:37:10 :
I'm helping a friend figure out what is causing the 251 in his RFPW to spew oil out of the dipstick - LOTS of oil. Here are the facts as I know them:
- The engine recently started blowing oil out of the dipstick.
- The engine has never consumed oil between oil changes (once a year), nor does it blow any smoke when driving.
- Two cylinders tested very low before he pulled the head: 38 lbs on #1, and 55 lbs on #5. All the others showed from 70 lbs to 88 lbs. The head gasket was in very good condition.
- The cylinder walls are worn smooth, with minor scuffing on all of them, and some more aggressive scuffing on #1, but not enough to feel with your finger or finger nail.
- When the engine is idling, oil vapors blow out of the oil filler when the cap is removed.
My first thought was that excessive blow-by was over-pressurizing the crankcase and causing the oil to blow out the dipstick. But I would think this would also cause the engine to smoke while driving. I also think this would show as oil consumption over time.
My second thought was that something has clogged the PCV valve, causing the crankcase to build up pressure and spew oil, which is aggravated by blow-by on #1 and #5.
I would appreciate any thoughts you have about this scenario.
Greg
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