compresion results on a 951
09-05-2003, 03:18 PM
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compresion results on a 951
car has 245000 km
1st 142 Psi
2nd 119 Psi
3rd 142 Psi
4rh 142 Psi
test was done on a full cold engine didn't run for one week. accordimg to my mechanic the readings
would be lower with a cold engine but if there is a problem it will show up on the results.
any thoughts? do I need to rebuild my engine now?
Konstantin
1st 142 Psi
2nd 119 Psi
3rd 142 Psi
4rh 142 Psi
test was done on a full cold engine didn't run for one week. accordimg to my mechanic the readings
would be lower with a cold engine but if there is a problem it will show up on the results.
any thoughts? do I need to rebuild my engine now?
Konstantin
09-05-2003, 03:29 PM
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How are the values with some oil in the cylinders? That can give you a hint about the rings condition, specially thinking about 2nd. Bad rings or bad valves...?
//Magnus
//Magnus
09-08-2003, 11:29 PM
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the head is new and the valves has been done just 6 months ago
here a video to see what I mean that the car smokes
http://www-public.tu-bs.de:8080/~y00...alom2smoke.mpg
Konstantin
here a video to see what I mean that the car smokes
http://www-public.tu-bs.de:8080/~y00...alom2smoke.mpg
Konstantin
09-09-2003, 04:26 PM
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I saw the vid.. it's hard to be able to tell you what the problem is. With oil smoke like that on decel, I'd lean towards a ring problem. Usually when it is a valve issue, you'll get smoke most of the time.
How did the bores look when you did the head? You could stick a boroscope in there and check now for scoring.
I'd also squirt some oil into the cylinders and check compression again to see if #2 comes up. If it gains 10-20 psi, you have a ring issue. If there is no change, do a leak down to help find if you are bleeding pressure around a valve or through the crankcase.
How did the bores look when you did the head? You could stick a boroscope in there and check now for scoring.
I'd also squirt some oil into the cylinders and check compression again to see if #2 comes up. If it gains 10-20 psi, you have a ring issue. If there is no change, do a leak down to help find if you are bleeding pressure around a valve or through the crankcase.
09-09-2003, 08:55 PM
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The walls were perfect! I mean absolut perfect! better than new.
I am worry since teh smoke is white and not black or blue.
Burned oil should make a blue smoke. Also I made 5 runs and only this one at this place had this effect. On teh otehr runs I couldn't see any smoke but the car definately needs oil.
Ok It is leaking a little from the oil pan gasket but it can use 1 Liter every 600 km.
I must make a leak down test or put some oil and check it again.
Konstantin
I am worry since teh smoke is white and not black or blue.
Burned oil should make a blue smoke. Also I made 5 runs and only this one at this place had this effect. On teh otehr runs I couldn't see any smoke but the car definately needs oil.
Ok It is leaking a little from the oil pan gasket but it can use 1 Liter every 600 km.
I must make a leak down test or put some oil and check it again.
Konstantin
09-09-2003, 09:03 PM
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While I haven't seen the video and I know you said the head is new....
I would still lean towards bad/worn valve guide/guide seals as smoking under de-accelleration is a common result from bad ones. Perhaps you had one or more seals pull off its boss.
Rob
I would still lean towards bad/worn valve guide/guide seals as smoking under de-accelleration is a common result from bad ones. Perhaps you had one or more seals pull off its boss.
Rob
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09-09-2003, 09:09 PM
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but then it would smaoke every time I deccelarate but it does not???
Konstantin
PS I just do not want to open the engine again
Konstantin
PS I just do not want to open the engine again
09-10-2003, 08:20 AM
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You might want to check the carterventilation.
When decellerating, the 2.0 barA overpressure in the inlet is changing to .4 barA underpressure.
This can do funny things like dumping oil and condensate in the inlet.
TakeCare
When decellerating, the 2.0 barA overpressure in the inlet is changing to .4 barA underpressure.
This can do funny things like dumping oil and condensate in the inlet.
TakeCare