Compression Test 1=180,2=0,3=180,4=0 :( ?
10-21-2006, 01:27 AM
#1
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Compression Test 1=180,2=0,3=180,4=0 :( ?
I am in the middle of what seems to be a very long, stressfull, belt and seal change. I replaced the front seals and cam housing seals, water pump, pulleys and belts. There are two times where I could see that I may have bent the valves. One was when I first put the tensioner back on. I released the arm on the tensioner, my slack went the wrong way and the crank went backwards. The second time I was getting frustrated and cranked the crank backwards by hand, causing the belt to slip. These issues were all by hand, the timing should have never been more than a tooth off prior to cranking with the starter. Anyhow, I could get it to run and it runs rough, so I decided to do a compression test and ended up with 180 on 1 and 3, "0" on cylinder 2 and 4. Are these the cylinders that typically get bent valves? Why did 1 and 3 not get bent? Is pulling the head my next step and can it be done with the engine in the car?
Argh
Argh
10-21-2006, 01:37 AM
#2
Lazer Beam Shooter
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No, the valves may be bent, however theyd have to be annhilated to pull a 0 on both cylinders.
My timing was off just enough teeth to pull similiar results on the 951, however I set everything back to TDC, and tried to start it agian. Fired right up!
Compression tests before were like 150-0-150-0.
Compression results afterward were 150, 150, 145, 150
My timing was off just enough teeth to pull similiar results on the 951, however I set everything back to TDC, and tried to start it agian. Fired right up!
Compression tests before were like 150-0-150-0.
Compression results afterward were 150, 150, 145, 150
10-21-2006, 01:50 AM
#3
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As long as you were turning it by hand I really doubt that a valve got bent. Pulling the head while the engine is in is the normal way head gaskets are replaced, lots of posts on that procedure.
First, do want Rock said.
First, do want Rock said.
10-21-2006, 02:33 PM
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Originally Posted by Bluesky4x4
I released the arm on the tensioner, my slack went the wrong way and the crank went backwards. The second time I was getting frustrated and cranked the crank backwards by hand, causing the belt to slip.
Argh
Argh
10-21-2006, 02:37 PM
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But you should still not be able to rotate the crank when you are putting the belt back on. It sounds like you are having trouble with the crank rotating when you tension. If the crank is locked, that wont be a problem.