Won't start, no spark, GM HEI ignition

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anothermammalwiththumbs

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Posted this on XS650 Garage, too...

My bike is kick-only (only because the starter doesn't work - I think this is a solenoid problem), and has been converted to a GM HEI ignition by a previous owner.
Borrowing 12v from a car battery, I get 12v at the red wire on the coil, but no spark. The coil reads .6 ohms, which other threads say is right.
I have a spare coil and a spare HEI unit, both of which I have swapped in with no effect. Also built and installed a Radioshack rectifier, and I have the Chrysler regulator on hand, but haven't installed it.
Another puzzler - the HEI unit did not appear to be grounded (it was mounted to the battery box) even while the bike ran well. Also can't figure out if there's supposed to be a condenser with it.

I put my meter between the coil and a plug, kicked it, and got nothing. Not sure if this is a resonable testing method, but I tried to just hold a gap for the spark and got nothing.
I'm not sure how the new HEI pickup works, or how to test it, and I can't find anything about how to test the HEI unit itself.

Wit's end is long gone, and and help will be much appreciated.
 
It's mrriggs's setup. 4-pin HEI module, dual output coil, toyota pickup sensor.
The HEI module was mounted to the battery box. I looked at the box to see if the guy had added a ground strap/wire, but can't find one, so it's either hidden or - damn - maybe I accidentally removed it when I put in the new rectifier. I'll check that in the morning.
Still, the bike had this no-start no-spark problem before i replaced the rectifier.

I checked for resistance across the pickup unit, and got ~160 ohms, ~180 as the tooth rotates past. Anyone know if this is right or what it should be?

Sorry about all the words...
 
I'm guessing this is a different Riggs setup than the Ford setup that uses the points (with condensers removed) as a trigger?
Don't want to sound silly, but is the fuel on? Double checked kill switch? The HEI should not need a case ground. Did you check primary, secondary and lead reasistance in your coil circuit? I'm assuming the .6 in your first post was the primary resistance. Meter between the coil and plug will do nothing for you, except possibly blow the fuse in your meter. HEI spark is not always the easiest to see. Not like a big blue magneto torch. Your setup should not require a condensor. The gap-type testors with the window are the best way to check that ignition pulse. You say you are getting 12 volts to the red wire on the coil, but no spark, so you are charging the coil (or should be) but if you are not getting a spark it is not being triggered by the pickup or the HEI, one or the other. Hope this helps. I'm not an electrician, but I'm reading my ass off on power generation and ignition!
 
Here's a link to my ignition setup: $19 junkyard ignition
From that thread, "Post by mrriggs on Mar 13, 2006, 12:46pm" says that the unit needs to be grounded through the mount holes. Dunno, maybe it's unnecessary...

I'm going to try to find info on testing the pickup and HEI unit, because those seem like the likely culprits. Any other guesses in the meantime would still be great.

Thanks guys.
 
GM modules do ground thru the screw hole on one end or the other. Has a metal sleeve on the end that grounds. it does need to be mounted to an aluminum plate that acts as a heat sink. I am running a gm module on my slant six mopar....
 
Any idea how to test an HEI module? I'd like to know for sure if that's the problem. I have two, and have put both in, grounded, with no luck.
Also, how do I test the secondary coil resistance? And what is "lead resistance" that jd750ace mentioned? I checked the one between the red and black wire - thought that was the primary, but now I'm not sure. It's a GM coil, same as Riggs'.
 
Ok, Autozone, Advance and Napa did not have testing equipment. A guy at Autozone managed to find the parts stats in his computer and I got a phone number for Wells, the supplier of the HEI unit.
Will call them tomorrow.

The coil is supposed to have .2 - .7 ohms resistance in the primary coil, and 6k - 11k ohms resistance in the secondary.
I just don't have any idea how to test the secondary coil. Across the two plug wire posts?

For everyone else's info, the part numbers are: Duralast coil - C849; Duralast HEI ignition module - DR100
 
the secondary resistance is read from the 12V input terminal (red wire spade terminal) to the output, where the spark plug wire goes on. (test each one, obviously) The Lead resistance is the resistance value of your plug wire, read end to end, in Ohms. Typical plug wires are 10-13K ohms per foot. Might check with Pep Boys, if you have one, for that HEI checkout, but if you have tried both, and it's not working, might not be the spot. Did you find anything out on the pickup coil?
 
Ok - for posterity:

Here are Wells/Duralast specs on parts for mrriggs GM/junkyard ignition, as well as testing diagrams:

Ignition Coils

Pickup Coils

There is nothing about the HEI unit other that a pinout diagram.

Parts on my bike, and - as far as I can tell - on Mr Riggs' setup in his original thread here are as follows;
Pickup coil: JA1013
Ignition Coil: C849
HEI Unit: DR100

Unfortunately, all my bits check out ok. What now?
 
Stupid question: Is your engine grounded to the frame with minimum resistance? Are you using a spark tester to check for spark?
 
I'm not using a spark tester, but I've checked the spark by just gapping it before, and could see it really clearly. I use some clip-on jumper leads so the plug is in place and have a friend hold them so that they're steady and easy to see.

I'll be checking the engine grounds tonight. I've got all the standard mounts, so I can't imagine how the whole thing could become ungrounded, but I guess that's the sort of thing that happens...
 
Starting to sound like your $19 scrap yard ignition is costing more all the time.
Leo
 
yeah... haven't spent too much on it at this point, but it's sure as hell costing a lot of patience.

This winter I might strip her down and give everything a good scrub and polish, neaten up the wiring, relocate components and whatnot.
One big thing I have to do is locate some power terminals under a sidecover so that I don't need to unbolt my seat (sort of tracker-style) from the frame every time it needs a jump.

There's always somethin.
 
Nah, I tried jumping it from a car battery. Checked for spark and positive voltage at the coil while it was hooked to that, too. Gonna slap it all back together tomorrow and see what happens. With any luck, I've fixed it by accident. :shrug:
Made a heatsink and ground connection tab for the HEI unit, because that thing really wasn't grounded. No idea how, but it was bolted to the battery box, and there's no ground connection there. So hopefully that'll fix it. Or at least eliminate that as the problem.
I'll check to make sure the engine has a good ground on it, too, just in case.
 

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