Mercedes Benz repair: oil consumption, oil pressure sender, crank case

Question
1985 280 se uses 1 qt every 75 miles
compression 150 runs great and smooth
does not smoke
sat from 1998 till 2004
92k miles
2.8 ltr inline six cylinder gas engine
any suggestions before overhaul

Answer
Answer:
Proper diagnosis.

Where is the oil going/coming from.

I looked at a Mercedes today, owner claimed one quart every 500 miles.
Owner thought rebuild was needed.

Two minutes of hands on diagnosis.
Head gasket bad = pumping oil into cooling system.

Leaking 1 qt every 75 miles = dumping oil...

Your catalytic converter should be glowing white hot?
Valve stem seals?
Front or rear main seal could have dried out and failed?
Valve cover leak?
Oil Pressure Sender leaking?
Are you building crank case pressure, and blowing it out?

Best advice:
Take it to a Mercedes specialist for diagnosis.