Compression test results .. engine wore out?
04-02-2006, 09:51 PM
#1
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Car: '85 TA
Engine: 350 turbo
Transmission: T56
Axle/Gears: 3.70 posi 9bolt
Compression test results .. engine wore out?
I did a compression test and here are the results:
122 -- 15
125 -- 134
130 -- 0
120 -- 30
(Front)
Something is obviously wrong with the drivers side. However, I think I figured out where all the blow-by is coming from. Also, the trouble with tuning my carb is probably related somehow.
What is surprising is how well it runs and it doesn't miss at all. So, what do you think?
122 -- 15
125 -- 134
130 -- 0
120 -- 30
(Front)
Something is obviously wrong with the drivers side. However, I think I figured out where all the blow-by is coming from. Also, the trouble with tuning my carb is probably related somehow.
What is surprising is how well it runs and it doesn't miss at all. So, what do you think?
Last edited by calebzman; 04-02-2006 at 09:55 PM.
04-03-2006, 12:37 AM
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Car: yy wife, crazy.
Engine: 350, Vortecs, 650DP
Transmission: TH-350
Axle/Gears: 8.5", 3.42
I think you need to do a leak down test. Don't assume the problem is the rings.
04-16-2006, 04:12 PM
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Car: '85 TA
Engine: 350 turbo
Transmission: T56
Axle/Gears: 3.70 posi 9bolt
I did a leak down test to see what was causing the compression to be low. I hooked an air compressor up to the 3 low cylinders and all 3 leaked the air around the rings. The engine no longer has any power and can't idle smooth. Also, I hear a knocking sound when I rev the engine a little. I was nervous b/c I just got back from driving to school which is a 60 mile trip. I noticed that I get blow-by when accelerating now (before it was only on deceleration). Is the engine dead? 
04-16-2006, 04:44 PM
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Car: 95 E-150 & 07 Kawasaki ZX-6R
Engine: A slow one & a fast one
Transmission: A bad one & a good one
Axle/Gears: A weak one & a chained one
With numbers like that....how does it still idle?? For those compression numbers, all on the driver's side.....head gasket or warped head??
04-16-2006, 04:57 PM
#5
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Originally Posted by calebzman
I did a leak down test to see what was causing the compression to be low. I hooked an air compressor up to the 3 low cylinders and all 3 leaked the air around the rings. The engine no longer has any power and can't idle smooth. Also, I hear a knocking sound when I rev the engine a little. I was nervous b/c I just got back from driving to school which is a 60 mile trip. I noticed that I get blow-by when accelerating now (before it was only on deceleration). Is the engine dead?
that's not how to do a leak down test. did you try a wet compression test?
04-16-2006, 05:11 PM
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Car: 95 E-150 & 07 Kawasaki ZX-6R
Engine: A slow one & a fast one
Transmission: A bad one & a good one
Axle/Gears: A weak one & a chained one
Originally Posted by ede
that's not how to do a leak down test. did you try a wet compression test?
04-16-2006, 05:21 PM
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Car: '85 TA
Engine: 350 turbo
Transmission: T56
Axle/Gears: 3.70 posi 9bolt
I shouldn't have called it a leak down test. I took the valve cover off and moved the test cylinder to top dead center. I then pressurized the chamber to hear where the air was leaking. The sound didn't come from the exhaust or carb, rather I heard it coming up through the head. I didn't get any measured value, but I was able to determine the problem area .. the rings or cracked/broken piston.
Now I just have to figure out where to get another engine.
Edit: There is definately a cracked or broken piston b/c of the noise in the cylinder. I had hoped it would have lasted until the summer..
Now I just have to figure out where to get another engine.
Edit: There is definately a cracked or broken piston b/c of the noise in the cylinder. I had hoped it would have lasted until the summer..
Last edited by calebzman; 04-16-2006 at 08:15 PM.
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