The compression test looks close enough for government work, i
don't think thats the problem, if you have a blown headgasket and coolant getting into the combustion chamber the plug usually is scrubbed clean frequently with a light coating of rust on the electrode, if yours are black or tan then thats not the problem most likely. If your pressure cap is releasing at too low a pressure then it can lose coolant there while your driving and you won't even notice it since it dumps out under the car. There's many places that you can have a cooling system leak on the m60 and not notice it easily. You need to take a radiator pressure tester and pressurize the system to normal pressures and then just watch for leaks, give it 20 or 30 minutes with it pressurized for a leak to show up under the car
12 to 14 bars is the normal compression. 12 bars equals 174psi approx. I wouldnt worry about your compression numbers, there's too many variable when you do the test. Did you hold the throttle body wide open? if not then your numbers will be lower, did you hear each the cylinder stroke at least 8 times on each one or until the gauge doesn't climb any higher? Your numbers look good enough to indicate that thats probably not the problem. Your more concerned about large variances between cylinders.
Quote:
Originally Posted by straighteight
After a long week of British rain I've now completed the compression test (see below). Could you guys tell me what you think of the results.
I also looked at the plugs and most seemed fine. A couple seemed a little black with some corrosion (cyl 1&5). What does a spark plug on a dead cylinder look like?
Cylinder No 1: 160psi
Cylinder No 2: 170psi
Cylinder No 3: 155psi
Cylinder No 4: 155psi
Cylinder No 5: 155psi
Cylinder No 6: 157psi
Cylinder No 7: 168psi
Cylinder No 8: 180psi
A lot of aux water pumps fail on the M60...
due to the heat created on that side of the engine bay (unlike I-6 M20, M50, M30, S38). The necks on the pumps crack apart similar to the way the radiator necks crack. I have seen 3 aux water pumps that were pushing out coolant when running because the hose was seperating from the aux pump with the neck inside of it.
Usually you see coolant on the ground as a result.....have you seen this?
edit: sorry, you said you don't see this.
Can you see dried up coolant covering anything in the engine bay?
Go yank the hoses connected to the aux pump and make sure they are tightly fitted and the aux pump necks are not broken.
Quote:
Originally Posted by straighteight
I've recently purchased a 94' 540i and I've been having a few problems. I'm getting a gurgling sound coming from the dash once the car has come to a halt and now have no heat what so ever. Once every month the coolant also seems to dissapear. I'd appreciate any suggestions you guys may have.