500 MJ Posted September 8, 2012 Author Share Posted September 8, 2012 In the below photo, how many teeth did it take to set the rotor from the right yellow mark to the left yellow mark? 1? 2? This is one tooth's difference. In this photo have you tried a timing light and watched the balancer vs. crank pulley marks? They should be nice and steady and advance smoothly as you rev up the engine. If it's jumping all around, causes include worn distributor shaft bearings causing side-to-side play and/or timing chain wear/slop, both of which can cause rough idling. I haven't done anything with a timing light. I can borrow one but I thought I would try to see what this did first... I was inside the engine when I had it on the stand and I replaced the timing chain as it was out of spec. according to the FSM. I replaced both gears and the chain with a new CLEVITE timing set. I have not noticed anything out of the ordinary with the distributor shaft when I have had it in and out of the block all of these times... FYI - The engine has 158K on it. I'll get back at it tomorrow, I finished the night off with taking the sway bar off of the front end to replace the bushings in it and pop it back on tomorrow morning. Cruiser54 - Thanks for the info on how to fix the harness... Link to comment Share on other sites More sharing options...
500 MJ Posted September 8, 2012 Author Share Posted September 8, 2012 Didn't get the chance to play this morning... hopefully tomorrow :roll: Link to comment Share on other sites More sharing options...
500 MJ Posted September 22, 2012 Author Share Posted September 22, 2012 Update - Just got back from a week long business trip to Chicago. No time to mess with wires tonight, but should get the chance tomorrow evening and ALL day on Sunday. I will keep you guys updated. Thanks, - Brent Link to comment Share on other sites More sharing options...
500 MJ Posted September 23, 2012 Author Share Posted September 23, 2012 FYI - All six wires joined in one location near the MAP sensor. I am assuming that the harness is original to the Jeep, the Jeep is a '90. Also, the factory splice was covered in Duct tape, but the splice was soldered. Digging further in tomorrow... Link to comment Share on other sites More sharing options...
cruiser54 Posted September 24, 2012 Share Posted September 24, 2012 Just keep checking the resistance as you go. Don't trust their crimps. I cut the crimps right out and them solder the wires in a bundle myself. Link to comment Share on other sites More sharing options...
500 MJ Posted September 26, 2012 Author Share Posted September 26, 2012 So I learned a lesson in all of this. Make sure you have good batteries in your ohmmeter before you use it for testing... I did the harness repair and tested my resistance again post repair and I got 3.4 ohms. I couldn't see how the work that I did still didn't do the trick so I started thinking about it and I looked at the battery in the ohmmeter - it was supposed to be good until 2002. I got a fresh 9 volt and retested my repair to find that the resistance is 0.4 ohms since I have done the repair. The Jeep doesn't idle any better - or worse - than it did before the repair. It still runs rich. I adjusted the TPS after the repair, it was way out of whack for where it needed to be for the 17%. It was around 10%.I fixed this and the Jeep gets up to speed now pretty good, I got it up to around 55 or 60 pretty easy. I've got some overdrive only vibrations that I'll need to track down, but thats another venture to worry about later...u-joints? I do think that I might have stumbled upon another thing to look into while I was messing with all of these wires to help the running rich problem. I am going to swap out the fuel injectors for a new matched rebuilt set that I have on the shelf and see what this does for me. I think I am onto something as I was playing with the wires and as I would move the wires for the injectors while the Jeep was running, it would affect the way it ran pretty drastically. I think these injectors could be the original ones, if that is the case they are well overdue for replacement... I'll probably get the chance to mess with this again on Friday night as the next two nights are taken for other things...thanks for the patience for my busy life. - Brent Link to comment Share on other sites More sharing options...
500 MJ Posted September 29, 2012 Author Share Posted September 29, 2012 Playing with this today, still having fun troubleshooting issues. I will update tonight when I'm done for the day. Link to comment Share on other sites More sharing options...
500 MJ Posted September 30, 2012 Author Share Posted September 30, 2012 I replaced all six fuel injectors and it helped things out. I am only able to start it in the shop because I have the bumpers removed and I am messing with the turn signal wiring as well, gotta love crimp-on connectors... It runs alot better now that it is getting fuel on all 6, I should have listened to the fuel injectors sooner with the stethescope - you can really hear them tick when they fire. Some of the old ones weren't firing when I checked them prior to the swap. I revved it up a few times and I got a few backfires from it, mostly on the peak of the rev and then letting it go back down to idle. My MJs will do this every so often so I'm not worried about it too much. Once I get the bumpers back on and the turn signals re-built I will get it out and see how it runs on the road. Link to comment Share on other sites More sharing options...
cz777 Posted October 1, 2012 Share Posted October 1, 2012 IIRC there is a procedure involving using a cutaway cap to index the distributor. Bring the engine to tdc, put on your cutaway cap, (cutaway at no. 1), the rotor should just be touching no. 1. You could just be one tooth off. I was after replacing my engine. It ran, but badly. Moved the rotor back one tooth, problem solved. Hope this helps. this is right way ...plug wire mount over #1 drill a hole in a cheap cap app. 3/8 hole and mount modded cap with rotor ....turn engine slowly by hand see the leading edge of rotor in the center of hole ...see if #1 is a TDC too this is old school but works Link to comment Share on other sites More sharing options...
cruiser54 Posted October 1, 2012 Share Posted October 1, 2012 Remove the distributor cap and cut a "window" into the side of the distributor cap at the #1 spark plug wire post . The "window" should be large enough to allow easy visual inspection of the position of the distributor rotor at the #1 spark plug wire post. Reinstall the distributor cap. Install a ¾” wrench or socket onto the vibration damper retaining bolt. Rotate the engine in a clockwise direction until the #1 cylinder is at top dead center. Align the timing mark on the vibration damper with the "0" degree mark on the front cover timing scale. The tip of the distributor rotor should be near the #1 spark plug wire post. Disconnect the distributor electrical connection. Remove the distributor holddown clamp, holddown bolt and distributor. Remove the distributor cap and rotor. Place the distributor housing upside down in a soft jaw vise. Scribe a line 1/2 inch from the end of the distributor locating tab. Cut the distributor locating tab at the scribed line with a saw. Remove any burrs and metal filings from the distributor. Reinstall rotor. If necessary, using a flat blade screwdriver, turn the oil pump gear drive shaft until the slot is slightly past the 11 o'clock position. The oil pump gear drive shaft is accessible through the distributor mounting bore in the engine block. Visually align the modified locating tab area of the distributor housing with the holddown clamp bolt hole. Turn the rotor to the 4 o'clock position. Lower the distributor into the engine block until it seats. The rotor should now be very close to the 5 o'clock position. Reinstall the distributor cap with the cutout "window". Rotate the distributor housing until the trailing edge of the distributor rotor tip is just departing from the #1 spark plug wire post terminal . Reinstall the distributor holddown clamp and bolt.. Reinspect the position of the rotor to the #1 spark plug wire post to insure that it has not moved. Install the new distributor cap, reconnect the distributor electrical connections. Revised 07/03/2012 I have a photo of the dizzy cap mod but don't know how to upload it for you. Link to comment Share on other sites More sharing options...
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