It’s odd both those cylinders can’t manage any pressure. That’s usually a catastrophic failure (valve and piston meet) or a stuck open valve. They are on two different banks.
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Compression test 01 Navigator
- Thread starter Fordgirl01
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Hold up is this the same bank dry/ wet? I think I confused myself....ignore my comment I was thinking you tested all 8 and this was a layout of both banks. I now see the D and W up top.
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Fordgirl01
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Yes same bank-dry and wet.
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stamp11127
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Looks like someone is going to tear down an engine....
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Fordgirl01
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OMG-do you think you can talk me through something like that?![emoji1694]
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Trainmaster
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If you're sure the compression test is correct, your next step would be to pull the valve cover and take a look at what the valves are doing. Hopefully your problem would be easily solved in there.
1955moose
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Anytime your compression doesn't budge after squirting oil in that cylinder, it's usually valve related. Bad rings or something bottom end will jump up. That's good news I guess. The low compression on 5,6,7 bug me though. A motor with that low of mileage, should be 140 or higher. Anyhoo, that drivers side valve cover needs to come off. Now you see why old school compression tests are still the best. A scanner couldn't pick up a wet test. I don't think they can. I think the gang here can walk you through the top end teardown/rebuild I'd get a Ford repair CD, I have a copy of one that I got a couple of years back from our departed friend Bob aka Bedrck 47. I'm not using it right now. Mines a 2000 year , Pm me if interested. I can throw it in the mail. You can mail it back if you don't want to keep it.
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Did you see the needle jump and suck back down quickly when you were cranking it?
Need to pull valve cover. It is not likely at not the most likely thing that you have a valve seat or other thing preventing sealing.
More likely that you have a follower off and intake is not opening so you get no air in to compress..or a valve is stuck open or bent(worse).
You need to inspect them and crank it with valve cover off (pull fuel pump fuse or relay) and watch to see if they go up an down.
My guess is you will find a "rocker" follower laying in the head jammed sideways and holding valve and spring down.
Need to pull valve cover. It is not likely at not the most likely thing that you have a valve seat or other thing preventing sealing.
More likely that you have a follower off and intake is not opening so you get no air in to compress..or a valve is stuck open or bent(worse).
You need to inspect them and crank it with valve cover off (pull fuel pump fuse or relay) and watch to see if they go up an down.
My guess is you will find a "rocker" follower laying in the head jammed sideways and holding valve and spring down.
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Fordgirl01
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I also have one of Bob’s repair cds but it was for my 04 expy. Thank you for your offer-I will keep that in mind if I end up needing it.
I sure do appreciate your help and I guess I will tear into the valve cover. I’m going to try another compression test just in case something went wrong, but I think I had everything the way it was supposed to be.
I’ll be sure to keep you posted!
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Fordgirl01
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The needle jumped up every time the engine cranked over until it appeared to reach a max number (except for #8 which did not move the needle at all). I cranked it over maybe 8-10 times for each cylinder.
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