| Author |
Message |
Timothy Fulmer (Tf308)
New member
Username: Tf308
Post Number: 24
Registered: 5-2002
| | Posted on Monday, November 11, 2002 - 3:18 pm: | |
Pete..I am in the middle of pulling my rear head now due to a 24% leak down in one of my cylinders. Mine was coming out of my intake valves. Things I am learning 1) What a (four letter word)ing pain it is to get the head off!
2) If it ran fine before, it is not worth this much trouble to fix. My problem was that I slipped while trying to break off the intake cam pulley. Then I did the leak down. So I dont know if it is a bent valve or just carbon. If you know it is not a bent valve..ie the car ran fine before...then do the following: 1) try some sort of fuel/valve cleaner and run the •••• out of the car. 2) make sure you are using the correct plugs. The new forza talks about using NGK 5 plugs. |
Bill V. (Doc)
Junior Member
Username: Doc
Post Number: 189
Registered: 9-2001
| | Posted on Monday, November 11, 2002 - 9:19 am: | |
Peter--from what I understand, a 10% leakage on a cold engine is fine. I bought a car with one cylinder reading 20% , when cold and the concensus of 3 mechanics and a # of chatters was that that was even OK. The car runs fine. However, thatcertainly wouldn't be a good reading on a hot engine though. |
JRV (Jrvall)
Junior Member
Username: Jrvall
Post Number: 52
Registered: 11-2002
| | Posted on Monday, November 11, 2002 - 8:36 am: | |
10% cylnder leakage is WELL WITHIN the acceptable standards for a good used engine.
The general rule of thumb is "more than" 10% (no not 11% lol) 'may' point to a problem. The test is subjective, like driving, it depends on who is behind the wheel as to the results one achieves.
Carbon on valves is very common and normal on older engines (30K mi. + & up). The quality of gas used, type of driving (lots of slow speed/in traffic), type of oil used all contribute to carbon build-up.
Yes the carbon can simply be cleaned off the valves. There are very good chemicals on the market specificaly for the purpose of removing these carbon build-ups. Wurth I believe has some and Lubro-Moly...both European Product Lines availible from most Euro Parts Supply houses..
The only reasons for a valve job would be...
1)Broken Belt = Bent Valves
2) Burned Valves
3)Blown Head Gskt, might as well refresh the heads while they're off.
4) Extremely High Mileage 70K plus |
Peter A. Costa (Fer__r__e)
New member
Username: Fer__r__e
Post Number: 1
Registered: 11-2002
| | Posted on Monday, November 11, 2002 - 8:20 am: | |
If you see carbon build up on your valves, does that constitute a valve job? Can this be cleaned with out taking the heads off? Leak down test results on a cold engine (engine on stand with no fluids) 10% leakage. No burning oil or neither had to add oil at any time for any reason. |