1976 jeep 4.2 six cylinder.
Developed a bad miss and loss of power. Put In new spark plugs and wires, new ignition module and had already put in a rotor. Did not really help much, developed a spitting noise from exhaust made me think of a burned valve. Did a compression check both wet and dry and the compression was good.
Put in a new distributor cap and reinstalled plugs that had got wet in rain. Before install of plugs, tried to dry them and sprayed NON FLAMABLE brake cleaner in to each plug to dry and clean. Did not realize the brake cleaner was not flammable until later. The jeep ran slightly better but still had a miss.
Disconnected battery ground cable from block and cleaned the ends as well as putting some electric tape where worn insulation was missing. Jeep ran much better but still has miss in it at idle, miss seems to be less at high rpm. Though it is running better I have a constant blue smoke from exhaust...it has never burned oil and have never had to add oil. When I checked wet compression, I put 4 squirts of oil in each cylinder.
Plan is to put a new ground cable on being as I did get good results when I cleaned it. Carburetor is not the best but I don't think that would produce the blue smoke.

Questions, how long should it take for the oil I put in each cylinder to be gone? Do you think the plugs that got wet should be replaced even though I put them in a short time ago?
Any comments will be appreciated very much. Sorry for the long post.

Pull plugs and turn it over a few times to blow it out. Use new plugs and gap them correctly. Double check the ignition wires. Blue smoke is oil, black smoke is gas, white smoke is water. I would test the spark at each plug prior to installing. You're wanting a bright blue spark. For full ignition test, open up an old plug gap to 1/4" and test it for spark to each ignition wire. A good ignition system will jump the 1/4" gap. I'd screw in the plugs before you do the 1/4" spark test to prevent a fireball or four.

Be careful making sparks over an open live cylinder spraying gas. We don't wanna change your nickname to Smokey.

Plug wires? A miss at idle and not at above 2000 rpms is typically ignition.

Even though somebody always tells me I'm wrong on these threads, I've been a mechanic for 28 years...

Have new wires, dist cap, coil and ignition module. Will double check spark plugs. if that is not it what might you suggest I check?

Thanks Cast I will follow up on the spark with new plugs.

Timing.

The cam and crank have Absolutely got to be in time. That's my next guess besides a bad distributor. Does it have eltronic ignition, I'm not an expert on anything much less keeps but... a 1976 could have bad points. When was the last time it ran right?

Jeeps not keeps

Texas Lefty I have changed the distributor cap and yes it does have the electronic ignition. Also put in a new ignition module. I did turn the distributor slightly in both directions and did not seem to make a difference. I put a new rotor in not long aqo when this first started. Under the rotor and on top of the distributor, there is a rubber piece. not thick and I don't know it's purpose. In any case it has a cut on it about half inch long. Does that mean anything?
I know on some of the older chevy's they would develop oil leaks via the valve guides. This engine is in the AMC family...do the AMC engines have this same valve guide problem?

Thank you for your time!

If it smokes at idle after start up it's probably not the valve seals or guides. Typically smoke at idle is rings. If it has electronic ignition the distributor is probably not stock. I'm not sure about the rubber piece inside the distributor.

If it were my Jeep I would not be worried about burning a little oil. The problem your describing certainly sounds like an ignition problem to me. If you've never replaced the distributor and your 100% sure that it's in time then... with out even seeing the Jeep (just guessing) sounds like a distributor problem. I would be checking actual voltage and continuity to ground at the distributor also

Wet compression was as follows,
Cylinder 1- 149,
2- 149
3- 148
4- 149
5- 151
6- 152
I thought this would eliminate rings being bad, perhaps not. Will check voltage and continuity next week-end. Thank you!

Again, it's not easy too troubleshoot thru the forum.

The compression is not super important at this point, I'm glad to see it's all about the same which tells me compression is not causing the felt missfire.

Like I've already stated Ignition.

Do the 1/4" spark test on all plug wires and get back to us. What's next if that flies Lefty?

How about start it and pull one wire at a time? If it doesn't stumble when pulled that could help ID a bad wire.

Does it have a stock exhaust manifold or header? If it has a header, after fresh/cold start, check temp on each header tube for one that is cooler than the others (not firing and/or not firing regularly). You can use a grease pencil, candle, drops of water, etc.

Good simple advice.

Cast I will do the spark plug test as mentioned and check spark from distributor. Will get back next Monday or Tuesday.

Thanks all.

I think TEXASLEFTY was on to something.

Pull your distributor and check the gear on the bottom of the dizzy shaft.
These Jeeps have been know to eat distributor gears after they get fairly worn.

If that's ok, then it may be worth your time to pull the front end off the engine (water pump, etc.) and check the cam timing gears & chain. If you have a lot of miles on that re-(factory?)build then there is a good chance you have a stretched out timing chain.

Not trying to stir the pot here but...............

If the timing chain stretched or the cam/crank gear jumped one or more teeth... I think it would have an extended crank to go with all the other complaints. The other compliant would not be a dead miss that goes away at higher RPM's I think it would be a slight miss with very low power at low rpms and more power than normal at higher RPM's.

No stirring thought...

I didn't mean jumped a tooth, I just meant the chain being stretched out.
Pulling one way and then another under normal driving conditions can result funky running.
(The cam timing advancing and retarding.) And going by the mileage, the factory type timing chains usually don't last more than 60-75k before they start stretching out where they are noticeable. Double roller chains last a little longer, but they don't put them on them at the factory.

I have an '81 v8 (360) that ran rough and funky, and when I put a new chain & gears on it, it ran smooth as glass.

If it had a stretched chain or jumped a tooth wouldn't there be backfiring thru the carburetor? Have not pulled the distributor. Jeep still has a slight miss at high idle speed. has enough power but also has too much blue smoke. Starting to think about valve guide seals and or a for sale sign.

There can be spitting back through the carb, I guess. But that is more typical of the distributor timing being waaay out of whack. In my experiences, spitting back thru the carb is typical of the distributor being 180* off, and it not running at all.