My 2004 Rubicon was giving me low oil pressure at idle when warm, and glitter in the oil, at only 128k. I think it spun a cam bearing. It's an engine out service, and since I wanted more power, I had an (alleged) engine builder I wheel with rebuild the bottom end with a stroker kit from cleggs. He claims to have built the stroker in his Jeep and it ran STRONG. Months later, he hadn't even pulled my engine, and was putting other jobs ahead of mine (I paid him half down). I reluctantly let him take a block he had lying around to the machine shop instead of my block. A couple months later, he had it back from the machine shop, but still hadn't touched my Jeep. A few months later...no progress, so I asked to go recover my Jeep, parts and machined block.
He had actually assembled the engine, but put his used head with god knows how many miles on it instead of my head! I recovered it, took it to a shop and had it installed within a week. First start and....it misfires badly at idle. The shop took it on a brief test to ensure the new clutch was working properly. I picked it up and prayed it would run better at break in. I started and idled at 2k (it doesn't misfire that bad above 2k) until temps started to come up, and then drove around 35-40 mph city streets for about 20 miles, keeping it around 2k even at stops, and it ran slightly less crappy afterwards. Slightly. It still felt less powerful than my old engine, and idled like crap. One cylinder doesn't fire at all at idle though. I also replaced the spark plugs and coil pack, but it made no difference. I looked for vacuum leaks and verified the injectors were working.
I asked the install shop to check it out. The put a compression tester on cyl 2- the most accessible cylinder, and it was 35 PSI! The engine builder claims my break in procedure was too aggressive and I fried my rings, which is BS. Then he threatened to "beat the life out of me" if I called him out again. (This is Billy Bryan of Edgewood New Mexico. Beware! Incompetent, lazy, and homicidally dangerous)
I figured I'd do a full compression test to see what I'm looking at. Here are the results...
Cyl Dry Wet %
1) 95 121 127%
2) 35 39 111%
3) 89 100 112%
4) 97 117 121%
5) 101 127 126%
6) 94 123 131%
Interesting points: cylinders 2 and 5 are the ones the computer says are misfiring, but those have the worst and best compression. It says 5 is the worst. Maybe my scanner has them transposed. Cylinder 1 is the one at the front, right? This is a 9.3 compression ratio so I was expecting pressures over 135. The interesting thing is only a couple cylinders get anywhere near that when wet. Of course, they should all go up SOME because the oil decreases the volume of the cylinder a little, as well as the improved sealing. They're still not going up anywhere near the level I expected though
Thoughts? Cyl #2 is particularly interesting because it barely changed, which suggests a bad valve, yes? I actually did that one a 2nd time using a LOT of oil and it still only got up to 60 (no doubt because the oil was taking a significant portion of the cylinder volume). Might my head just be worn out, or do you guys think the rings are toast, too? Also...has anyone had any luck about suing a mechanic? I'm already in this for over $5k and 8 months of wasted time, and I'm worse off than when I started.
Thanks
He had actually assembled the engine, but put his used head with god knows how many miles on it instead of my head! I recovered it, took it to a shop and had it installed within a week. First start and....it misfires badly at idle. The shop took it on a brief test to ensure the new clutch was working properly. I picked it up and prayed it would run better at break in. I started and idled at 2k (it doesn't misfire that bad above 2k) until temps started to come up, and then drove around 35-40 mph city streets for about 20 miles, keeping it around 2k even at stops, and it ran slightly less crappy afterwards. Slightly. It still felt less powerful than my old engine, and idled like crap. One cylinder doesn't fire at all at idle though. I also replaced the spark plugs and coil pack, but it made no difference. I looked for vacuum leaks and verified the injectors were working.
I asked the install shop to check it out. The put a compression tester on cyl 2- the most accessible cylinder, and it was 35 PSI! The engine builder claims my break in procedure was too aggressive and I fried my rings, which is BS. Then he threatened to "beat the life out of me" if I called him out again. (This is Billy Bryan of Edgewood New Mexico. Beware! Incompetent, lazy, and homicidally dangerous)
I figured I'd do a full compression test to see what I'm looking at. Here are the results...
Cyl Dry Wet %
1) 95 121 127%
2) 35 39 111%
3) 89 100 112%
4) 97 117 121%
5) 101 127 126%
6) 94 123 131%
Interesting points: cylinders 2 and 5 are the ones the computer says are misfiring, but those have the worst and best compression. It says 5 is the worst. Maybe my scanner has them transposed. Cylinder 1 is the one at the front, right? This is a 9.3 compression ratio so I was expecting pressures over 135. The interesting thing is only a couple cylinders get anywhere near that when wet. Of course, they should all go up SOME because the oil decreases the volume of the cylinder a little, as well as the improved sealing. They're still not going up anywhere near the level I expected though
Thoughts? Cyl #2 is particularly interesting because it barely changed, which suggests a bad valve, yes? I actually did that one a 2nd time using a LOT of oil and it still only got up to 60 (no doubt because the oil was taking a significant portion of the cylinder volume). Might my head just be worn out, or do you guys think the rings are toast, too? Also...has anyone had any luck about suing a mechanic? I'm already in this for over $5k and 8 months of wasted time, and I'm worse off than when I started.
Thanks
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