No spark (follow-up for Mike ...and anyone else who can help!)

Ahhhh thanks Bill. I definitely have that wired in wrong. I'll give'r a whirl tomorrow and see if she finally fires. If not ...back here I come!

I run 2 new wires to do the 'Nutter' bypass rather than mess inside the harness.

To put it simple, the orange and purple wires at the ignition module connect directly to the orange and purple wires going into the distributor. The rest of the wires get left alone.

If you still have no spark, verify the ignition module has a ground. I use a booster cable from the battery negative to clamp on things to make sure they are grounded.

You also have a pickup coil inside the distributor that acts like breaker points. You can test this with a 'digital' multimeter set on ohms. The book reading on the two wires coming out of the distributor need to be between 400 and 800 ohms it says. Mine failed at 405 ohms I think it was.

Then if still no spark, I would change the ignition module for a good one. No way to test that puppy. Do 'Not' get a 'Wells' module. I have seen 2 and heard of a mess more come dead in the box and they fail really fast.

Unless this failed after trying the wiring, I would be suspecting a hard part failure. Changing wires won't help that.

Mike

griff>

The PartsSource here has a diagnostics tool that can check the ignition module. I took it in twice and it passed all inspections. Is it possible this test isn't that great?

Well, I have heard of a parts place testing them, but have no experience with that. Non of the places around here test them. I have a spare I use for testing purposes.

The modules also seem to fail when hot if it intermittent or just die totally, so likely yours is ok. How is the distributor pickup coil?

Mike

griff>

On Mon, 04 Jul 2005 12:25:17 -0400 in rec.autos.makers.jeep+willys, Mike Romain wrote,

I had the intermittent failure when hot syndrome. I took my ignition module to an Auto Zone store, where they have a fancy machine that tests all kinds of electrical parts. The module failed the test, I replaced it, and I haven't had that problem since. It didn't have to be hot to fail the test, either. Apparently it was good enough to make a spark when cold, but way way below spec.

Good to know, thanks. I will start asking around.

I have seen a wells module replace a 'bad when hot' one only to do the same thing again. A third didn't work, so the garage figured it was a bad one and said see and put the second back and sold him a computer, after they sold him a coil..... I got the vehicle brought to me after mega bucks were spent and I tagged the 'bad when hot' right out of the box module after testing the pickup and grounds.

Did you get your wiring figured out?

Mike

OOPS, you aren't the OP, ignore that bit.

OK, Mike & Bill I owe you guys a beer. It turned out (after ALL of this) to be the computer. I did all that bypass stuff with the wires and the hoses and it got spark and is now running and idling fine. It's out of time, obviously, but that's for another day - at least I was able to back it out of my driveway and back in again to verify she works. Now I gotta clean up that mess of hacked wires and hoses all over the place ;p

Thanks again for all your help!

BTW, Mike, where in Ontario are you? Do you ever do runs up to Thunder Bay area?

Mike, I had problems with 2 bad Wells ign. modules in a GM so when I took the second one back I had them test the new one before I took it. Something like 4 out of the five they had in stock failed right off the shelf. Needless to say I will carefully consider the length of the walk home before I even think about a Wells part anymore.

Actually two more questions for you guys ...

In reference to:

1. How/where do you guys suggest to create the air leak?
2. How do you tell if the metering pins are in the full rich position?

Thanks!

griffin '85 CJ7 4cyl

I like Labatts. ;-)

I am currently stuck in Toronto so Thunder Bay is 'way' up there. We get up as far as Huntsville pretty regularly, maybe this weekend even and have run up in Tamagami which is way up there too.

Are you up in that area?

As far as ll the hoses go, I just left my air filter flaps, EGR, canister and PCV systems in. The rest is trash.

For the carb, you can just pull off the PCV line to make it go full rich 'when the computer is working'. If the computer is dead, this will not work.

When I put a carb kit in, they are easy and only $20.00 or so, I use needle nose pliers to set the pins full rich. If the stepper is off the carb, you can finger pull the pins out and they will set full rich when the unit is put back in because the pins bottom out or I can reach down from the top and just gently pull the top pin out until it stops. The bottom pin is in lockstep with it. You will likely see carbon marks on the pin where it normally runs at which is close to half way out if it was working.

You then can set the idle mix screws down front.

I also 'highly' recommend you verify the idle tubes are clear before trying to set the mix. If there is junk in them, the mix will not stay stable, it will be different every time it starts up.

Here is a good link to a test for and if needed fix for the idle tubes. The tool used can be obtained from any welding supply store, it is used to clean torch tips. I have the mini file set.

Mike