Jumped timing???
hopefulcj
Jeeper
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- Location
- north florida
- Vehicle(s)
- 1980 CJ7-258 I6, MC 2100 carb, team rush upgrade, T4, D300 tcase, D30 w/aussie locker in the front, AMC20 open, I think PO put 4.88s in the diffs, 35,000-135,000 miles, you pick. 4"susp lift, 2" shackle, 35" <-BAD WORD-> cepek AT's on black steel wheels, 1 1/4" spydertrak wheel spacers, most everything else i believe is stock, finding things out as I go
About a month ago I bent the 6th cylinder rod guide/bridge. Before finding this, my mechanic thought I might have an intake valve not seating, and this might have thrown off the timing. Now that is all fixed, and the jeep was running fine. I recently put on a MC 2100. I set the timing to 8*BTDC with a light, and the jeep ran like . This scared me. I remembered about the timing chain issue before so I set the timing by ear like the mechanic did, I got the jeep running pretty good, though it still lacks some power and lags if I really get on it. Their is no pinging or anything. The notch on the wheel points straight up (12 o'clock) with the current timing. It should be pointing more at 2'ocllock to even be read on the TDC scale.
This leads me to think that the timing chain jumped, since I can get the engine running, but the timing is not set where its supposed to be.
-Engine has probably been rebuilt, engine is all orange including some of the lower end gaskets.
-Mechanic replaced all upper gaskets.
I am going to try to set the timing by vacuum gauge.. warm up to operating tem, plug into manifold vac., plug advanced vac nipple, turn dizzy to get the best pressure, then turn back 1 hg.
Should I go ahead and replace the timing chain and gears? The mechanic was going to do this but decided not to since we didnt have to machine the head? Will I damage the engine internals ig I keep driving it like it is? I have read that it will on some of the searches I have done, and I have also heard that this is normale with old engines and to just time it by ear since its an older engine, and the factory timing specs arn't accurate anymore.
Thanks, thanks, and thanks again. Im getting long winded like my dad.
Jacob.
This leads me to think that the timing chain jumped, since I can get the engine running, but the timing is not set where its supposed to be.
-Engine has probably been rebuilt, engine is all orange including some of the lower end gaskets.
-Mechanic replaced all upper gaskets.
I am going to try to set the timing by vacuum gauge.. warm up to operating tem, plug into manifold vac., plug advanced vac nipple, turn dizzy to get the best pressure, then turn back 1 hg.
Should I go ahead and replace the timing chain and gears? The mechanic was going to do this but decided not to since we didnt have to machine the head? Will I damage the engine internals ig I keep driving it like it is? I have read that it will on some of the searches I have done, and I have also heard that this is normale with old engines and to just time it by ear since its an older engine, and the factory timing specs arn't accurate anymore.
Thanks, thanks, and thanks again. Im getting long winded like my dad.
Jacob.
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