!! Compression Readings WTF HELP
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!! Compression Readings WTF HELP
Cylinder #1 170psi
Cylinder #2 120psi
Cylinder #3 180psi
Cylinder #4 140psi
Cylinder #5 170psi
Cylinder #6 130psi
Cylinder #7 130psi
Cylinder #8 130psi
What do the gurus think? I think its not a good thing. All the noise I am getting is from the passenger side valve train. I ******* hate my car.
What are the assumption/ possibilities?!???!
Cylinder #2 120psi
Cylinder #3 180psi
Cylinder #4 140psi
Cylinder #5 170psi
Cylinder #6 130psi
Cylinder #7 130psi
Cylinder #8 130psi
What do the gurus think? I think its not a good thing. All the noise I am getting is from the passenger side valve train. I ******* hate my car.
What are the assumption/ possibilities?!???!
#3
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How many miles on the motor ? Could be carbon buildup on the valve seats, or bad guides, I have also found if you open the TB blade ,that will lets air in the cylinder to give a more accurate reading, or it could just be worn or bad rings. The worst is a broke ring landing. Like above, a wet test can eliminate the bad rings by squirting a little oil in the cylinder to seal the rings.
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Start the engine and let the engine worm up and then check your compression, Are your rockers adjustable or not ? Where its a new engine the ring may not be seated yet. Or the rocker arms may be to tight. Or the push rods are to long. I really don't know your engine, that why i'm giving you different thing to look at that may cause your problem
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When I did the break in process everything ran great. Snapped a 10 bolt and the day I started the car to move it from the house garage to the shop garage it started acting funny...IE noise from the passenger side head/valve train. I thought the stock rockers had finally had enough so I ordered a set of harland sharp non adjustable 1.7s. Went to install them and the threads had started to pull out of the head Dart Pro1 205cc. Sent heads to get repaired. Just got around to getting the engine buttoned up and the noise is still there. My gut feeling tells me that there maybe a damaged/collapsed lifter (comp cams OE-R hydraulic rollers. Thing that makes me even more nervous is that the noise and trouble is where I had a lifter break and wipe a cam. The lifter got lodged in the bore. The machine shop was supposed to make all of that correct and good again. I should have checked out the lifters while the heads were off but didnt think to as i had "found" the problem in the heads. So shame on me if it is.
Pushrods are confirmed twice 7.4" comp 1 pc chromemoly
Pushrods are confirmed twice 7.4" comp 1 pc chromemoly
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Rebuilt 346
ARP rod bolts
Cammotion 227/231 .598/.598 112+4 camshaft
Comp Cams OE-R (pro magnum) lifters
Comp Cams 1 pc chromemoly pushrods 7.4"
Dart Pro 1 205 CC heads (assymbled with .625 springs single coils.
Harland Sharp roller rockers
UMI valve cover spacers
boltons
spec 4 clutch and bolt ons
Something is deffinetly up it ran better on my old tune then it does now (also is getting a new crankshaft position sensor when i get it back in the garage.
ARP rod bolts
Cammotion 227/231 .598/.598 112+4 camshaft
Comp Cams OE-R (pro magnum) lifters
Comp Cams 1 pc chromemoly pushrods 7.4"
Dart Pro 1 205 CC heads (assymbled with .625 springs single coils.
Harland Sharp roller rockers
UMI valve cover spacers
boltons
spec 4 clutch and bolt ons
Something is deffinetly up it ran better on my old tune then it does now (also is getting a new crankshaft position sensor when i get it back in the garage.
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yeah let it run for 10 minutes then do the compression test again.I just did a test on a 383 stroker and got 4 that were 170 and 4 that were 210.I just cranked the starter for 30 seconds a few times to get a little oil moving on the cylinder walls(it had been sitting for a few weeks).And then did the test again and all were 210.If the cylinder walls are kinda dry your readings will be all over.So at the very least crank it with the starter for a couple minutes in 30 sec intervals so you dont fry the starter.hope this helps.
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thanks guys the car has been sitting pretty much for almost a year ... since about last july. I had another technician buddy say that the lifters probably need ran a bit to get more oil to them to pump them up all the way he is going to stop by to take a look see tomorrow.
#12
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Comp R lifter like low preload and preferably an adjustable rocker. What is your preload value on those lifters? Too much preload will hang the valves open on those when they pump up.