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I've got a '73 CJ5 with an '84 AMC 258 i6 / 4.2l . It's got a Weber 2bbl and a DUI distributor all installed by the PO. Prior to tearing down the jeep, everything ran fine and I didn't touch the engine at all. Now that everything is back together, I can't get this thing to run properly. It will start up and idle OK but with any gas, it revs and dies and often reverses the engine before blowing white smoke out the carb. I've cleaned out the carb and cleaned up the Distributor cap and rotor point and it's still doing the same thing. It starts up great every time but won't go above idle.
When it starts and idles, is it rough? I only ask because it may be a stuck Exhaust port in the head? Just thinking out loud...
I'm not too familiar with that motor, how hard is it to remove the valve cover to inspect what is working with running?
I think you can run the motor "easily" (as in don't rev hard etc) while the covers off and see if you can see on of the rocker's not working right?
Anyways, as you know, I'm not the expert on this motor type, but just what I was thinking since I'm assuming sat for a while? Maybe a oil treatment of some type may help to "free" it if I'm right?
I didn't do anything to the engine but it sat for about 4 months while I was rebuilding the rest of the Jeep. I acts like it could be the timing but I'm not sure how it could have gotten that way. Also, at idle it runs fine for about 1 -2 minutes and then dies.
Finally got a chance to work on the Jeep but I'm still having the same general problem. When it would idle, I adjusted the distributor in both directions but where it was seemed to be the best so I don't guess there's a timing issue. I took apart the carb and cleaned it out pretty well and now, it'll start but not stay running before dying, blowing white smoke, and reversing the engine just before it dies. Again, this thing ran fine before but after sitting for a few months, it now doesn't. I didn't repair, modify, or do anything else to it while rebuilding the Jeep with the exception of re-wiring the whole thing. Any ideas are appreciated.
I've tried to rotate the distributor in both directions and it only made it idle worse. That's my entire knowledge of adjusting the timing so if there's something else I can do, please let me know. Thanks!
Can you bring #1 to tdc on compression stroke? Not being smartass... Just making sure
Then see where your rotor is pointing... Should be close to #1 spark plug wire... If too far off to adjust, may have slipped a tooth... Since u didnt have thedistributor out at all, probably the chain??? Not positive on this so someone correct me if wrong please..
I didn't do anything to the engine but it sat for about 4 months while I was rebuilding the rest of the Jeep. I acts like it could be the timing but I'm not sure how it could have gotten that way. Also, at idle it runs fine for about 1 -2 minutes and then dies.
I'll check where the rotor is pointing with #1 at TDC tomorrow and where it's at. I don't think it's the choke, which is electric, as it acts the same whether it's plugged in or not. I have noticed that the choke gets pretty hot when plugged it. Is that normal?
Not sure on electric but sounds like its still trying to choke mitor when warmed up already... Look where the butterfly is sitting on top of carb after warm... Should be mostly open as opposed to when cold it will just barely be open...
Again im not to familiar with electric ones but i think thats your ticket... Someone please correct me if wrong!
The butterfly is pointing straight up/down. When I manually close it, it'll die soon after.
I've checked TDC and the rotor is pointing at the #1 wire. It'll start and idle OK but after a few seconds, it dies. Not as much white smoke as in the past.
1978 CJ7
Silver paint with black hard top on 33" radials & eagle alumium rims. Good looking ride and have done lots of work to make it look and run great.
Stock equipment is 258 carb, power brakes, power steering, hard top & hard doors (per vehicle gross weight) tilt steering wheel, big brake package with large rotars & drums, T18 Trans with low 6.4 granny gear, Dana 20 transfer, Dana 30 front axle, Dana 44HD rear axle with 3.73 gears. True Trac ft & rear.
I was around jeeps in the 70's and drove a 1973 Jeep Truck. My family had 4 jeeps at the time. We also joined a jeep club back then too. So about 6 years ago looked for a Jeep CJ and found the vehicle above.
i hate to say and im sure ill hear about it but, 4 months is a long time for a weber to sit unused with gas in it, like most carbs, but especially a weber. could need a good cleaning and rebuild kit. i wanna say you still have a slight timing issue as well. if you got the cash to spare you should buy a timing light or borrow one from a buddy, so you can set the timing, and rule it out.
I'll check where the rotor is pointing with #1 at TDC tomorrow and where it's at. I don't think it's the choke, which is electric, as it acts the same whether it's plugged in or not. I have noticed that the choke gets pretty hot when plugged it. Is that normal?
1986 cj7 258, t-176 4-speed, d-300, moser one piece axle in back in amc 20,G2 4.10 gears front and back, detroit truetac front and back,G2 4340 chromoly front axles in a d-30, 4" rough country lift, 33" tires
i hate to say and im sure ill hear about it but, 4 months is a long time for a weber to sit unused with gas in it, like most carbs, but especially a weber. could need a good cleaning and rebuild kit. i wanna say you still have a slight timing issue as well. if you got the cash to spare you should buy a timing light or borrow one from a buddy, so you can set the timing, and rule it out.
When setting the timing found out what rpm you are suppost to set the timing at. The chiltions says 9 btdc A mechanic I know said 9.5 Still others say 8 but never said was rpm to set the timing at. I was scraching my head tring to figure this out, and look down at the sticker by rad, If you still have the sticker any way. Mine said 12 dregees btdc at 1600 rpm. It runs like a champ now, better gas mileage and every thing. Now I dont know where the other timeing sujestions came from, I even checked the timing at an idel after I set it to 12 and at an idle on mine is 750. It was 6 btdc. Mine is a 86cj7 AMC 258 i6 / 4.2l with a bbd carter on it. But it should still run at 9 at an idle mine did just not as good as now. Oh and also when setting the timing disconcect the vac advance to the disturbitor, and plug up the hose.
1978 CJ7
Silver paint with black hard top on 33" radials & eagle alumium rims. Good looking ride and have done lots of work to make it look and run great.
Stock equipment is 258 carb, power brakes, power steering, hard top & hard doors (per vehicle gross weight) tilt steering wheel, big brake package with large rotars & drums, T18 Trans with low 6.4 granny gear, Dana 20 transfer, Dana 30 front axle, Dana 44HD rear axle with 3.73 gears. True Trac ft & rear.
I was around jeeps in the 70's and drove a 1973 Jeep Truck. My family had 4 jeeps at the time. We also joined a jeep club back then too. So about 6 years ago looked for a Jeep CJ and found the vehicle above.
I've got a '73 CJ5 with an '84 AMC 258 i6 / 4.2l . It's got a Weber 2bbl and a DUI distributor all installed by the PO. Prior to tearing down the jeep, everything ran fine and I didn't touch the engine at all. Now that everything is back together, I can't get this thing to run properly. It will start up and idle OK but with any gas, it revs and dies and often reverses the engine before blowing white smoke out the carb. I've cleaned out the carb and cleaned up the Distributor cap and rotor point and it's still doing the same thing. It starts up great every time but won't go above idle.
When setting the timing found out what rpm you are suppost to set the timing at. The chiltions says 9 btdc A mechanic I know said 9.5 Still others say 8 but never said was rpm to set the timing at. I was scraching my head tring to figure this out, and look down at the sticker by rad, If you still have the sticker any way. Mine said 12 dregees btdc at 1600 rpm. It runs like a champ now, better gas mileage and every thing. Now I dont know where the other timeing sujestions came from, I even checked the timing at an idel after I set it to 12 and at an idle on mine is 750. It was 6 btdc. Mine is a 86cj7 AMC 258 i6 / 4.2l with a bbd carter on it. But it should still run at 9 at an idle mine did just not as good as now. Oh and also when setting the timing disconcect the vac advance to the disturbitor, and plug up the hose
Seems there is a bit of confusion on how to set the time on a jeep CJ
The "COMPLETE" and fully functional "COMPUTER" controlled jeep CJ's will be timed at 1600 rpms as 1986CJ7 has said...
If the computer, computer controled carter carb, and all the sensors and not there and working..... then do not time your CJ like this, at 1600 rpms... The AMC Computer can only take out or lower the amount of ADVANCE.... it was timed at 1600 rpms, .... used the knock sensor, O2 sensor, to adj "take out advance" the computer could remove/retard the time and adjust the carb settings...
Since the Poster has a 73 CJ with a 80s engine with a after market carb and distributor he will NOT be timed at 1600 rpms. He will time at idle with the vac advance hose disconnected from the distributor and plug the rubber vac line with a golf tee or similar.
AMC engines like 33 to 35 deg of total advance. HEI distributors are known for having more than this. The guys that say 12 deg of initial advance are putting in 1/3 or more of the advance in initial advance or a base line of advance... The initial advance never comes out its a base.... the mech advance and vac advance is what makes the engine work well and work with the load and operation of the vehicle...
With a proper functional distributor, initial advance of 4-8 deg is a very good range. I do not knock at 8deg but use 6 deg initial. Lower your initial advance and your CJ will start better too.
The distributor advance chart....
Is in the 78 and 79 FSM, Field Service Manual.... Once the computer is removed both the 70s and 80s jeeps can and should use this Advance Curve to set up your AMC engines. There are manual, autos, CJ and FSJ charts in the manuals.
ps
Jeepers that have a 80s jeep CJ and the computer is removed and/or have a aftermarket carbs need to modify the stock distributor so it works properly or change it out.... Most of the change is opening up the mech advance slots so the computer vitange distributor that comes with 5 or 8 deg slots can have/ use a normal amount of advance like 15 degrees the engine can acutaly use... this is what will give you hwy and higher rpm performance & efficiency... Easy to do just go slow with file or small grinder so you do not make the slot toooooooo big and go slow.... Use balancer tape to verify your work.... This limitation is one of the main reasons the hei seems to be a good change.... Learn to correct your old duraspark distributor and you will like that one tooo....
Poster sorry for going off track on the distributor and time.... get some fresh gas in there and get a base line of function and see where we are...
Holy that's some good information. I've completely drained the tank and fuel lines and replaced it with new fuel but still having the same problem. I've also removed and cleaned the carb with no improvement. I'm now going to get a timing light and try to figure out how to properly set the timing.
Also, the distributor is an aftermarket DUI if that makes any difference.
that's some good information. I've completely drained the tank and fuel lines and replaced it with new fuel but still having the same problem. I've also removed and cleaned the carb with no improvement. I'm now going to get a timing light and try to figure out how to properly set the timing.