Electronic Ignition and Timing Question...

As I told you all before, I just replaced my stock ignition system in my '62 CJ-5. I used a Pertronix Flamethrower coil and an electronic distributor I got from Quadratec, I believe. Could have been Novak?... It is a nice setup. The distributor even has a fake oiler spout with a spring-loaded cap to keep with the looks of the early jeeps that actually had them. Nice for restoration.

Anyhow I have it installed and set the timing by ear, so to speak, until I could buy something I haven't used in years -- a timing light. The one I got is a nice Bosch unit. They have come a long ways since I got my first one. This one has all kinds of features on it.

When I hooked it up, I found that I wasn't too close on the "timing by ear" I was 15 degrees advanced. So I bought it back down to 8 degrees BTDC, which was the recommended value for the setup I have. Seems to idle nicely and accelerate quickly off of idle, too.

The questions I have are these: 1 -- I know that in systems with vacuum advance, etc., like I used to work on, you were supposed to disconnect the vacuum advance hose and plug it before measuring your timing. On an electronic system like I have, once the idle is set correctly, is there anything I need to do to ensure the distributor is not advancing my timing at idle so I can get a correct timing measurement? I don't see how it could, but then I have been blindsided before.

I see no means of the spark being automatically advanced when the accelerator is hit. How is this accomplished? Anyone know? I should have kept the timing light hooked up and hit the accelerator to see if the spark advances at all. If not, then what? Seems to run fine, but if the spark is not advancing, this goes against everything I learned as I grew up.

Please advise...

 

"I should have kept the timing light hooked up and hit the accelerator to see if the spark advances at all."

This. Wouldn't it answer your concerns?

 

So if the distributor does not have a vacuum adv canister then you will have all the advance done mechanically by weights and springs.

 

Yeah, but I was wondering how advance was done on an electronic distributor. I am just always curious how things are done when a meld takes place between old and new technologies. Like Walt says below, there must be some kind of centrifugal advance under the reluctor/pickup plate. I will have to check it out. The centrifugal advance was frozen on my old distributor and I was getting no spark advance at all. Thanks for the input...

 

Did a full investigation on this thing today, trying different things, and if anyone gets a setup like I have, here is what I found...

The distributor does advance the spark, but it seems to follow rpm increase with a very slight lag, so I would assume there must be a mechanical advance system in it. RPM's have to increase before the system operates and that is the way the centrifugal advance should operate by design.

The other thing is that you do not have to change anything to set the initial timing. Set it and forget it. The distributor takes care of the rest.

Later....

 

Yep the advance system is under the plate.

 

Walt, being one who tests complex high voltage electrical power systems, I like the quote in your signature. However, I have fixed many an electrical piece of gear with hammers. Have a good day...

 

That goes along with ... "If your only tool is a hammer, every problem looks like a nail." ??

 

Haven't heard that one before, but I am adding it to my repertoire. One of my favorites for describing overkill is, "That's like putting a candle out with a hammer". Working on jeeps, I think this statement is applicable at times...

 

I don't remember exactly, but it went something like as soon as you start swinging a hammer under the hood, everything fragile or close needs to be replaced afterwards and you probably still have the same problem you started with.

 

Good reason not to carry a hammer in your under seat tool box!

 

They just bounce around and make a lot of noise, anyway...

 

I know, I know this needs to get on topic, but you guys got me chuckling!

 

or... "if at first you don't succeed, try a bigger hammer."