Finally got everything back together and now I have no spark. We've tried everything we can think of including putting a new module in for the aftermarket HEI conversion. Have I pulled a brain fart and forgotten something easy? The distributor is turning (tach moves).

shmoky

 

Heard of a guy that left the rotor out and went nuts trying to figure it out. No, seriously, could have a bad coil.

 

What do you mean by 'aftermarket HEI conversion'? If you mean a points elimination kit, that's not an HEI system. You might want to go back to the original set up to see if that works.

 

Thanx Mike I thought about that too. Will probably try that later today.

shmoky

 

This happened to my '69 L71 a few years ago...same as you...no spark. It turned over fine but simply would not fire. I checked all over and when I removed the cover to the shielding around the distributor, the car started and ran fine. I put my hand near...not touching mind you, but near the distributor...ZZZAAAPPPP!!!! What a jolt I got...thought I'd have to go into a dark room and check my 'nads to see if they had become night lights!

Turns out the coil wire boot had developed a pinhole and the spark was grounding out against the lid to the shielding cover, even though it has an insulator inside it (which had a small burn mark). When I removed the lid the spark went where it was supposed to go and the car started and ran.

Never overlook the most basic and obvious. The spark will leak out if you give it a path to do so.

In my case all it took was a new boot on the coil wire and I was good to go...and the jewels still performed at their normal optimum level!

 

probably another kinda ridiculous question, but are you getting a spark through the wire? might just have to replace those...

 

Great ideas guys but still have a problem. I'm not using the cover (yet) until it is running so that isn't the problem. The wires were brand new just before the motor was rebuilt. Also picked up a new coil and will try that and the old points system hopefully tonite.

Where is the external ballast resistor located on the car? Want to check it out. I know the coil doesn't have one in it.

The ignition system I'm using is CraneCams Fireball XR-i ignition. (points conversion ignition system) With a rev limiter.

shmoky

 

stupid idea but it is easy to hook the power wire up in the wrong spot. ive done it with an hei distributor.. or are you getting power to the distributor when cranking?????

 

I have had my fair share of electrical gremlins seeing as i am on my fourth engine swap.
The best thing to do is take a break and get back to it on a clean slate.
Start from the beginning and when you are taking your break reread the instalation instructions for both the "points to electric" dist conv and the ignitin box. I have discovered while reading the directions again that i did something wrong. Next I would go back through mythodicaly starting form the top to be sure everything is hooked up right:
1.coil
2.cap
3.rotor
4.wires to the right spark plugs and tight connection to the coil
5.correct color wires from dist to ignition box (forgot to plug this in twice, very frustraiting)
6.correct wires from ignition box to coil (i have several times crossed the + and -)
7.correct power wires connected to the proper relays and or resistors
8.Connected ground wires ( i have forgotten this before!)
9.if you have a relay or using a flemsy wire adaptor to your fuse panel check those, replace the the relay if you can't test it and replace the fuse even if it looks good
10. replace the rev limitor plug to a higher one for now, if its a rotory or dial in rev limitor change the settings and be sure to look back over the directions for the ignition box setup if to be sure all dials are set right.
11. A common mistake i have made is the wires from the ignition switch to the box. Some times when using original wires for a conversion the colors are off or some wires are no longer needed. You may need to referece a wire diagram for your car to be sure you are connecting to the correct wires
12.After you run down all the wires and EVERYTHING is where it is supposed to be check for a spark with the wire and the plug off the car.

I know this may seem trivial but even some of the most accomplished mechanics have to go back to the basics especially when it comes to electrical issues.

Good Luck,

 

ballast resistor is on the firewall pass side near the dist. those conversion kits require these

 

Well................... we now have spark. Doesn't seem like a real big spark but there is a spark there and looks like it should be enuf to start it. But still no firing. We double checked the TDC. Because we do have a spark we didn't put the original points back in but may try that tomorrow.

We think that it is possible that the module for the points conversion may not be getting close enuf to the distributor shaft. So may file the screw mounting holes so they are even more elongated than originally and get it closer yet. When we do the test (according to instructions) with a test light on the coil it says the light should flash on and off as the motor turns over (distributor rotates). IT DOESN'T The light just goes dimmer and pulses but NOT off and on. So we feel the module is not switching FULLY on and off as it should.

Great post wrc69v. I got a second opinion (another mechanic that is better at electrical and he started at your step 1 and carried on thru most of the rest. I'm thinking it is a problem with the new points conversion system and am willing to go back to just plain old points and worry about electronic LATER. (I want to drive and am going with impatience)

Enuf for tonite ... will get back at it after work tomorrow. Thanx for everyones help and ideas. Keep 'em coming.

shmoky

 

Its not a cheap alternative but the MSD billet corvette dist was one of the best purchases of my ignition system. I have never had a single problem and it has moved with me through all of my 4 engines.
Good Luck!

 

This car does not have a firewall mounted ballast like a C2. The resistance is built into the wire itself. I'm not sure if these conversion kits should have a resistance wire or not.

 

Thanx Mike, I'm not sure if this system should have a resistor wire either. We tried running it without and with but still have problems.

Battery was dead today, (charger screwed up) so will get at it tomorrow. If it doesn't give us something right away we are pulling the conversion kit and going back to original points to see if we have anything with them.

shmoky

 

Took off that crappy piece of junk (conversion kit) and put the old points back in. First turn of the key and we had VROOM VROOM.

Will take it for a drive on thursday as I have to go out of town tomorrow. A friend has a video camera and we should have a clip for you all (if I can figure out how to post it).

shmoky