Time for new motor??

[JScritch]

1992 BMW 525i -- Auto -- 101,000 miles -- M50

Got back from vacation and went to start the bimmer and it would start. Just cranked and tried to catch every once in awhile but that's all it would do.

Pulled plugs and they are all wet so it's getting fuel.

No codes stored.

Checked coils and they are each hot and each plug has spark.\

Checked timing chain and tensioners. All seem ok and cams are in proper position.

Did compression test dry:
#1=50 / #2=80 / #3=75 / #4=40 / #5=0 / #6=100

Did compression test wet:
#1= 100 / #2=125 / #3=160 / #4=100 / #5=50 / #6=100

Did leakdown test:
#1= 80% / #2=40% / #3=40% / #4=65% / #5=75% / #6=25%

What do you think?

[Bill R.]

oil in the cylinders like you did for the wet test and try starting it again. Some peoples m50's seem to lose the ring seal when setting for awhile. Once you get it to start if you check the compression again you'll find out that its fine. Squirt oil into cylinders and crank for a short while with the gas pedal to the floor , then crank normally and you should be able to get it to start.





1992 BMW 525i -- Auto -- 101,000 miles -- M50

Got back from vacation and went to start the bimmer and it would start. Just cranked and tried to catch every once in awhile but that's all it would do.

Pulled plugs and they are all wet so it's getting fuel.

No codes stored.

Checked coils and they are each hot and each plug has spark.\

Checked timing chain and tensioners. All seem ok and cams are in proper position.

Did compression test dry:
#1=50 / #2=80 / #3=75 / #4=40 / #5=0 / #6=100

Did compression test wet:
#1= 100 / #2=125 / #3=160 / #4=100 / #5=50 / #6=100

Did leakdown test:
#1= 80% / #2=40% / #3=40% / #4=65% / #5=75% / #6=25%

What do you think?

[BillionPa]

the ring seal can be "slowly" fixed by adding lots of molydenum disulfide to the oil, as it bonds with the metal under pressure. you will probably need 10000 miles before compression is back to spec.