Frustration! That's putting it mildly.

I didn't receive the spreadsheet. Maybe my email junked it. Can you send again to bill dot james at clough dot com dot au
Any info could be useful at this stage.

I haven't got spark at the coil secondary, so that eliminates the rotor, although I did check it.

Loren, I am in the middle of setting up a test rig to measure all the points you raised.
Unfortunately, wifey want to go boating this afternoon (35*C here) so I will get back into it later today or tomorrow and report the results.

JOY! Sort of ...
 

http://forums.pelicanparts.com/uploa...1330865594.jpg

http://forums.pelicanparts.com/uploa...1330865830.jpg

http://forums.pelicanparts.com/uploa...1330865861.jpg

A picture's worth a thousand words. :)

I have to say, for anyone trying to diagnose ignition failure, if the usual tests don't come up with a result, this is the way to go. For a couple of hours time to yank the parts, dummy up some wiring and test them all on the bench independently of the car, it is time well spent.
Actually, I was sure that one of these components was faulty, so I spent a bit more time to build a test board with the intention of handing the whole assembly off to an "expert" to troubleshoot in the event that I had no spark. I figured that this was likely to be easier and cheaper the towing my car all over town. I was very pleasantly surprised when everything worked as it should.

I have now confirmed that both coils, both Bosch and Permatune CDIs and my complete distributor are all OK. The obvious conclusion is that there is a wiring problem in the car's CDI/dizzy/coil circuit.
Obviously, I have tested all wires for continuity and earth leakage (100 times!), but I'm beginning to think that maybe something is breaking down under load. Regardless, I will rewire the coils, grounds and the green dizzy wire.

Loren, thanks for steering me in the direction of bench-testing the whole set of parts. I'm just pissed that you didn't suggest it sooner! ;)

I'd like to get my hands on some new coaxial cable to make up a "green wire" for the distributor sensor. Anyone got a source for this? I can't find anything locally that comes anywhere near the same cross-section size. Mind you, I don't see why it needs to be as heavy as it is for a piss-ant 1VAC and next to no current!
I might test the theory tomorrow, but I suspect that for a test rig like the one I put together, you might get away without using coaxial cable if you route it away from other wires. I used coax because I happened to have a short piece in the "might come in handy box".

"I will rewire the coils, grounds and the green dizzy wire."

Focus on the green wire, as it's a common problem as they get older,
i.e. The ends near each connector tend to short. Hook everything back
up and measure the A.C. volts of the green wire at the CDI while
cranking.

Bill: I've built my own "green wires" using various coax cable. It is a PITA. Search some for green wire and Early_S_Man. The hard part is threading the cables into the distributor.

BTW, the green wire connection is the worst electrical design ever.

Nice test setup, are you 100% confident that your rotor and distributor cap are OK? It would not be hard to pull the ignition wires from the car and connect up 6 sparkplugs layed all in a row on an earthed metal surface. It will look fantastic with the lights out if nothing else.

can we convince you to get rid of that permatune ?

I did run the test rig with one plug lead connected so I could test the rotor. Worked fine, but no real load of course.

I initially thought it was the Permatune that was the problem. I have since had it tested by a shop and on my rig with no problems evident, so no, I won't be scrapping it just yet.
You're not another closet Permatune basher, are you? :rolleyes:

I have made up a completely new CDI/coil/dizzy harness which I have tested on the test rig. Now Ijust need to fit it all back into the car and keep my fingers crossed.

:D :D :D
All's well. Car runs fine with new CDI/coil/dizzy harness.

I made up my own "green wire" from the CDI to dizzy connector using some shielded twisted pair cable left over from knock sensor wiring on my other current project 3.6.
Each of the core wires was a bit light (0.3mm2) so I joined the pair at each end to give me 0.6mm2 core wire. The shield was also only 0.3 so I beefed it up with a 0.5mm2 single wire running alongside. Heat-shrinked the two together and it seems to work.
Even though the relay panel braided ground strap was in place, I also ran a new ground wire from the CDI [31/1] to a good engine ground to be sure.
ALL connections are crimped and soldered.

It's a bit of a pain that I still don't know exactly what the problem was. All the original wiring measured up OK for continuity and earth, so it looks like I was chasing a dud connection that only ocurred with everything connected up in the car.

Thanks guys for your assistance and perseverence.

Permatunes simply seem to have a high failure rate reported.

"I made up my own "green wire" from the CDI to dizzy connector"

Hopefully the re-wiring resulted in the correct polarity on the distributor signal.
A reverse polarity may not be noticeable at first, but will result in the timing
being off as the RPMs increase and a poor running condition.

Old post but had a question if you please.
I am having problems crank no start.
I tested between terminal 7 and 31d setting my meter at V~200
I am getting a reading of 00.8 is this correct?