Hello.

Anyone with experience in overhauling the B5254S ?
I have a 1994 850 which consumes oil - more than 1 liter per 1K kilometers
In the past I've replaced the valve seals and the seals on the camshafts and crankshaft.
The mileage is 360K ( kilometers )

My question is : Do these engines have a lot of wear in the cylinders at this mileage?
Can I expect that I need to bore the cylinders or is it normally enough to replace the rings ?
I'm not keen on getting stuck with a dismantled motor without a plan

The compression is 10,8/11 bars on all cylinders except for #4 which is 9,5
When adding oil is shows 14 ( due to haynes is should be 13,5 ? )

 

If neglected any motor will wear out sooner than designed to. You say that it seems that wear is 20% on most and nearly 30% on #4. That's pretty bad. I have 225,000 miles (362,102 KM's) on mine and my compression numbers are within specs.