Hello,

I hope this subject has been raised before, but just in case, I would like to comment on oil filters.

Starting with the B18 engine, the oil filter became a spin on type filter and it came with some special features not found on most filters of the time, an anti-drain back valve and a pressure relief valve.

These features, especially the anti-drain back valve, are CRITICAL to the longevity of Volvo engines with spin on oil filters.

Without the anti-drain back valve, the oil in filter will drain back through the oil pump back into the oil pan, thus causing the engine to run longer without oil pressure during restarts, thus causing premature wear on the engine bearings.

The pressure relief valve is there to allow oil to flow to the engine bearings in case the oil filter element becomes plugged. Better to have non-filtered oil going to the bearings than NO oil going to the bearings.

I use Mann and Mahle oil filters.

I have some customers that insist on original Volvo oil filters ONLY.



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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90501