Bad exhaust valve?

[bjl4776]

I finally got my 95 M3 into the shop the other day. I did a compression test on it and it pulled 200-210psi on cylinders 1-5 and 170 on cylinder six. I put some oil in the cylinder and tried again and still got 170. So i get the leakdown tester out and I have 0-10% leakage on cyl 1-5 and 70% on cyl 6. It was definately coming out of the exhaust. Anybody ever have this happen to them. The car runs fine and pulls as hard as other 95s I have driven. It only has a rough idle when i come down from high revs and has 20"inHG vacuum at idle. All of the plugs looked fine with a tanish tint to them. Im not in a rush to fix it since it is my daily for now. But if there is anything else i should worry bout because of this it would be nice to know. Also, is there any difference between a 95 M50tu head and the M3 head besides the cam. Because if it is i can make a weekend project out of it and swap the head off of my 325is project track car and then build my M3 head to the specs I wanted to for the track car. I know it doesnt take much for these valves to show a bad leakdown because I had to put new valves in the 325is and the exhaust valves were only bent .002-.003 and 5 out of six of them were 5-15% leakage. Is it possible the car was money shifted slightly to only cause one cylinder to show problems?

[Bill R.]

tight exhaust valve on that cylinder... although if you've had it that way for very long, its probably burnt now..



I finally got my 95 M3 into the shop the other day. I did a compression test on it and it pulled 200-210psi on cylinders 1-5 and 170 on cylinder six. I put some oil in the cylinder and tried again and still got 170. So i get the leakdown tester out and I have 0-10% leakage on cyl 1-5 and 70% on cyl 6. It was definately coming out of the exhaust. Anybody ever have this happen to them. The car runs fine and pulls as hard as other 95s I have driven. It only has a rough idle when i come down from high revs and has 20"inHG vacuum at idle. All of the plugs looked fine with a tanish tint to them. Im not in a rush to fix it since it is my daily for now. But if there is anything else i should worry bout because of this it would be nice to know. Also, is there any difference between a 95 M50tu head and the M3 head besides the cam. Because if it is i can make a weekend project out of it and swap the head off of my 325is project track car and then build my M3 head to the specs I wanted to for the track car. I know it doesnt take much for these valves to show a bad leakdown because I had to put new valves in the 325is and the exhaust valves were only bent .002-.003 and 5 out of six of them were 5-15% leakage. Is it possible the car was money shifted slightly to only cause one cylinder to show problems?

[bjl4776]

That engine has hydraulic lifters doesnt it? Which is not adjustable. If it is solid lifters im not looking forward to removing the cams to adjust with shims.

[Jon K]

Hydraulic

[Bill R.]

e34 m5




Hydraulic