What next (electrical/starting problem)

'85 Jeep CJ7 4cyl 2.5L. Fixed the timing chain and reassembled yesterday. Started up but didn't have a tach so we couldn't set the idle speed and timing properly. Because the distributor was moved it's way off time (it should be 12 BTDC and is like 16-20, not to mention the idle speed is a mess). I tried driving it but it had absolutely no power and if I let off the gas even a little it would backfire. So today I get a laser tach and my timing light and disconnect the proper stuff to set the timing and plug the vacuum, etc. When I go to start it - nothing. It just turns over and over but never fires. At one point I almost got it to start but then it flooded. After that it would just do the same turning over with no apparent spark. I took the #1 plug wire and tried to get a spark on some metal but there was nothing so I tried the center plug off the distributor and got nothing there (tried it both grounded and not grounded). Next up I check my voltage readings. I get 12V across the battery and 12V across the electrical coil on the firewall when I go straight from the coil connector (the black connector that slides over the coil) to the battery but ONLY when it is disconnected from the coil itself. If I put it on the coil I get 6V. I'm assuming this is wrong. I just replaced the coil and had my control module tested and still no spark and still 6V reading. Where do I go from here?! All my connections seem to be connected and all vacuum hoses/etc seem to be properly connected. The only thing that appears wrong is that there are two red wires on my black connector on the top of the electrical coil and one of them goes no where and I can find no where to connect it.

Thanks!

Reply to
griffin
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So I tried disconnecting the plug that goes into the distributor (breakerless) and when I ran the multimeter across the coil I now get 12V. Does this mean the problem is in the distributor? How do I fix this?

Reply to
griffin

When you turn the key to run, the coil red wire should see about 9 volts. If you put the meter on the green wire from the ignition module, it should read 5 or 6 volts.

The red wire that broke off is the wire that goes from the coil to the starter solenoid. It hooks on the small side post or ties in with the light blue wire there. This is the power to the coil when the starter is turning and must be hooked back up to get any spark.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

griff>

Reply to
Mike Romain

K I looked at the starter solenoid on the bellhousing and there is one big black wire running to the far side of my starter relay mounted on my passenger wheel well. The one red wire on the electrical coil cap seems to run to one of the little rubber caps that connects onto the screw on the starter relay (I'll confirm this later with the multimeter cuz the wire gets lost in a wire bundle). The other red wire is really really short and isn't broken off ...it's disconnected. There is a long female black connector on the end that connects to no apparent place.

I'm wondering if something inside the distributor didn't blow. My dad is familiar with some distributors but this one (the manual calls it "breakerless") has him confused. We are unable to get the rotor off to see where the three wires go inside of it or how it works. Is there a solenoid in there? Could something inside have gone screwy? If so, how do we take it apart?

Also, if anyone has wiring schematics for '85 CJ7 (4 cyl 2.5L), if they could send them I'd be so grateful. The wiring on this thing looks like a box of phone cords and it makes no sense. There's been too many hands in there messin stuff up.

Thanks!

disconnected

Reply to
griffin

When the starter turns, it takes all the power so you get a direct from the battery via the relay power to the coil. If you do not have this, you have no spark when the starter is turning.

The black connector is for a capacitor.

Inside the harness about a foot or so away from the coil, the red wire splits at a crimp connector into one fat red rubber one and one that goes to the starter relay. The soft fat one is the ballast wire that provides power when the key is in run. It is about 6' long ant terminates in a crimp connector up by the brake booster with a brown wire going to the alternator. You have verified power there already, you are missing power when the starter is turning so you have no spark.

A multi meter on continuity would show if the coil red to the relay is ok.

You have a pickup coil in the distributor that can be tested with the meter on ohms. It should have between 400 to 800 ohms.

The cheap Haynes CJ manual has a wiring diagram that is spot on for the

80's CJ's, I have rewired several using it.

Mike

griff>

Reply to
Mike Romain

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