keep an eye on that breather tube, it sucks a bunch of oil on my 79 TD, so I know what you may be going through.
since you fixed the exhaust valves, you may have more compression in those pots, and now have more blowby, and your breather may be drinking it all in, but it's hard to believe two quarts in 10 miles... through the breather.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!