Compression test
#1
Compression test
I put a compression test on my 7.3 .Every cylinder got to only 100 psi.It seems odd that there wasn't a few cylinders that went higher or at least some difference in readings.This is the second powerstroke to do this.i pulled the first engine out for low compression and put this engine in its place.Could I be washing the cylinders out trying to get them to start? I know people are going to say rings but can there be any other plausible reason for such low consistent readings? Can the truck even fire on 100 psi?
#3
#5
I've had some engines that have sat for a while, been cranked over and not starting for a while register next to nothing on compression. I had a gas engine that showed 20psi, 80, 30, 120 etc I thought for sure it was a dead engine. Was a running pulled jy motor with only 60k that just sat a few months. Once I fired it up and let it get up to temp, maybe the rings sealed better or something it was like 160 within 5psi across all 8. Maybe you're seeing something similar? I'd try a new tester too.
#6
Has this engine run recently? Or had it sat for any time? I just picked up a dead Kubota tractor I bought this weekend, it looked "great" inside, I still got compression (by hand) and smoke while cranking it, it even sputtered for 30 seconds on its own before I pulled the head. I noticed the heavily pitted cylinder sucking back through the exhaust so I knew the exhaust valve wasn't sealing right.
#7
I went a bought a second diesel compression tester and again I only registered 100 psi.I added oil to a couple of the cylinders and they came up to 200 psi.This motor sat in a junk truck for several years and haven't run yet.I am hoping I can add oil to the cylinders and re lube the cylinders and hopefully start the engine
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#8
I went a bought a second diesel compression tester and again I only registered 100 psi.I added oil to a couple of the cylinders and they came up to 200 psi.This motor sat in a junk truck for several years and haven't run yet.I am hoping I can add oil to the cylinders and re lube the cylinders and hopefully start the engine
#12
Fuel pressure won't matter for ether. It's strange you can't get it to fire on any cylinder either. Ether would eliminate the fuel injeciton system entirely as a culprit it usually helps determine the valves and piston/ring health. Have you checked the turbo for a blockage from a mouse? Have you tried spraying the ether after the turbo, directly into the head intake?
#14
Even with 200 psi it will be hard to to stay running. If it looks anything like the pictures posted forget it.
Your obviously not getting fuel to the cylinder, so you can crank and spray all day without it maintaining a turnover.
Unfortunately I'd agree that motor is not worth the time of trouble shooting.
Your obviously not getting fuel to the cylinder, so you can crank and spray all day without it maintaining a turnover.
Unfortunately I'd agree that motor is not worth the time of trouble shooting.
#15
If you haven't remove the intake Y after the turbo I would still check there incase something made a nest that got sucked into the turbo. Starting fluid will make things fire missing half their cylinders. I can't see water or other damage to all 8 cylinder beyond getting it to fire. It may not be getting air or starting fluid through it if you were spraying through the turbo. Can you smell the starting fluid leaving the exhaust? Putting your hand over the turbo while cranking does it pull good vacuum?
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