Pertronix Ignitor II bench test fail

[timsch]

I recently put a Pertronix 91247 Pertronix Ignitor II in my 12v '49 front mount dizzy 8N w/ original coil. It never did anything but sputter on trying to start. Today I finally pulled it back off to bench test it and I'm getting no voltage at all, at any point in the rotation of the shaft.

I've hooked it up like this and double checked my connections and made sure nothing wasn't touching that shouldn't be. Igniter sleeve was still in the dizzy base. The magnet sleeve I assumed to be the aluminum plate everything is connected to - that's what it looks like to me below:

Is there anything I should check before assuming it's a bad module?


edit: I should have added that when checking for spark before pulling it off, only one of four had a decent, constant spark across 1/4" gap. 2 had no spark at all, and another had a weak spark occasionally. Battery was checked good

 

[zuhnc]

How old is the unit? DO NOT use solid core wires; they will kill the module, and, per Pertronix, will void your warranty. They specify resistor-type wires. BTDT. My first on my 8N lasted about a week, and had to walk back to the shop for the points I took out. Put a new module in, with proper wires, and haven't had any problems for four years now.

 

[timsch]

Unit is brand new. I didn't use solid core wires. They're the stranded copper core type, and they are brand new also. I made those up to replace my old ones when I was having spark issues after putting in the EI.

 

[zuhnc]

Is the copper core a resistance wire? By solid, I mean no resistance built into the wire, whether stranded or solid. A stranded copper wire would have no resistance, but be flexible. You MUST use some sort of resistance wire. It will not affect operation of the ignition system at all.

I have used Accel brand resistance wires on all my equipment I have a Pertronix unit installed on with no issues. Some have been in operation for six or seven years.

 

[timsch]

Damn. Looks like I fried my unit. Ignorance is not bliss.

I sure wish the terminology were more intuitive.

 

[wore out]

Damn. Looks like I fried my unit. Ignorance is not bliss.

I sure wish the terminology were more intuitive.

Don't feel too bad, sometimes the #&@* things just die out of spite, right out of the box. Others are still working after 25 ir more years.

 

[zuhnc]

Yes, sometimes electronic stuff just dies, for no apparent reason Pertronix states in their literature to use some type of resistor wire, or a block resistance in the lead. I remember when little screw-on resistor blocks were available for plug wires, mainly to mitigate interference with the (AM) radio. Sometimes Pertronix might replace the unit for free/warranty; won't hurt to ask. zuhnc

 

[wore out]

Yes, sometimes electronic stuff just dies, for no apparent reason Pertronix states in their literature to use some type of resistor wire, or a block resistance in the lead. I remember when little screw-on resistor blocks were available for plug wires, mainly to mitigate interference with the (AM) radio. Sometimes Pertronix might replace the unit for free/warranty; won't hurt to ask. zuhnc

The bottom line is that for the price they get for a buck or two of electronic components they are not overly reliable or robust.

 

[zuhnc]

Seven years on a Pertronix ignition is not "overly reliable or robust"?

In the 60's I built a lot of electronic ignitions for our vehicles. Even then, most were more than "a buck or two". Parts prices HAVE come down, but that is due mostly to improved manufacturing and engineering processes.

Regardless, the EI sure beats cleaning, regapping, changing, etc., points and condensers after a few hours of operation, in the dark, raining, Not to mention erratic operation if the distributor gets some moisture in it and fouls the points. zuhnc

 

[wore out]

Seven years on a Pertronix ignition is not "overly reliable or robust"?

In the 60's I built a lot of electronic ignitions for our vehicles. Even then, most were more than "a buck or two". Parts prices HAVE come down, but that is due mostly to improved manufacturing and engineering processes.

Regardless, the EI sure beats cleaning, regapping, changing, etc., points and condensers after a few hours of operation, in the dark, raining, Not to mention erratic operation if the distributor gets some moisture in it and fouls the points. zuhnc

When the kits were fifty or sixty bucks, a failure now and then probably wasn't a big deal, now that they are a couple of hundred bucks, not so much.

It would be interesting to know the failure rate vs. the much maligned Ford TFI modules.

 

[Factotum]

It unfortunate that they aren't 100% reliable. Or at least put into the "that never fails" category. My son has a "77 Kawasaki KZ650 that he'd like to
"upgrade" from points. But if the electronic ($250) one fails, he's stuck at the side of the road, if the points fail, they usually can be made to work enough to get you to a better place than the side of the road. I would think this is the same on a tractor, minus the stormy rainy weather, but you'll get back to the barn. Electronic? Not so much. Tough call.

 

[HFJ]

The bottom line is that for the price they get for a buck or two of electronic components they are not overly reliable or robust.

i believe their biggest problem (or at least easiest to solve) is their wording of the instructions about the plug wires. i've seen a lot of people that think multiple solid wires are ok and were led down the path to the same mistake.

if there's a metal conductor in your plug wires, or any other number of them wrapped, twisted, etc in parallel, do NOT use these wires with a pertronix. i think their failure rate would drop significantly if they cleaned up the instructions on the plug wires.

in the meantime, 3 years on a pertronix 91247 here. my arthritic hands love it.

 

[zuhnc]

From the Pertronix web site:

Its very important to verify that your spark plug wires are compatible with the ignition system, or any on-board electronics in general. Solid core wires have a copper or stainless steel conductor and generate excessive Electromagnetic Interference (EMI). This EMI can create confusion with electronics and ultimately damage them. With all PerTronix ignitions we recommend that a suppression style spark plug wire (also called carbon core) be used. The suppression wires do an excellent job of controlling the EMI with no degradation to the ignition performance.

If, you don't know how to identify the type of wire on the engine. Here's a articular written by our friends at Hot Rod Network showing pictures of the different wires. It should help with figuring out the spark plug wire being used on your engine. Keep in mind PerTronix ignitions need carbon-suppression, or spiral-wound wire: https://www.hotrod.com/articles/1006rc-ignition-wiring/
Also, in regards to leaving the ignition switch on:

With Ignitor electronic ignition systems, leaving the ignition switch in the run position when the engine is not running, can cause permanent damage to the ignition system, and related components. This does not apply to the accessory position of the ignition switch. Ignitor II and Ignitor III ignition systems have protections built into them that turn off the system prior to damage.

Bold and color mine. Seems pretty clear to me. Once again, most of us tend to forget to RTFM! zuhnc

 

[TheOldHokie]

When the kits were fifty or sixty bucks, a failure now and then probably wasn't a big deal, now that they are a couple of hundred bucks, not so much.

It would be interesting to know the failure rate vs. the much maligned Ford TFI modules.

Well I can tell you the failure rate om my TFI was a lot worse than reports of Pertronix failures.

As bad as the TFI was the failure rate of crankshaft position sensors on the two Caddilac Cateras I owned was much worse. They werr so bad I kept a hot spare in the glove box of both cars.

The ignitor module embedded in the distributor on the Ford Probe GT my son owned was on par with the crankshaft sensors. Kept and still have one of those on the shelf.

My point (no pun intended) being electronics fail and you have to weigh the advantages of Pertronix over points knowing you might have a failure you cant fix with a screwdriver and your girlfriends emery board

TOH

 

[Eman85]

Well I can tell you the failure rate om my TFI was a lot worse than reports of Pertronix failures.

As bad as the TFI was the failure rate of crankshaft position sensors on the two Caddilac Cateras I owned was much worse. They werr so bad I kept a hot spare in the glove box of both cars.

The ignitor module embedded in the distributor on the Ford Probe GT my son owned was on par with the crankshaft sensors. Kept and still have one of those on the shelf.

My point (no pun intended) being electronics fail and you have to weigh the advantages of Pertronix over points knowing you might have a failure you cant fix with a screwdriver and your girlfriends emery board

TOH

Also the fact that you're not going to go to local parts store and buy another Pertronix part, it would have to be ordered and deliverd. TFI you could buy most anywhere 24/7 if needed. A filed set of points will get you up and running for quite a while if you have to wait for a new set.

 

[TheOldHokie]

Also the fact that you're not going to go to local parts store and buy another Pertronix part, it would have to be ordered and deliverd. TFI you could buy most anywhere 24/7 if needed. A filed set of points will get you up and running for quite a while if you have to wait for a new set.

So keep a set of points in the toolbox. That and a screwdriver will get you out of the field.

TOH

 

[JMOR]

When the kits were fifty or sixty bucks, a failure now and then probably wasn't a big deal, now that they are a couple of hundred bucks, not so much.

It would be interesting to know the failure rate vs. the much maligned Ford TFI modules.

Well, Ford did pay for towing, TFI and labor.

 

[TheOldHokie]

Well, Ford did pay for towing, TFI and labor.

That is news to me. It was always on my dime.

 

[Eman85]

So keep a set of points in the toolbox. That and a screwdriver will get you out of the field.

TOH

I just came across my special socket for TFI module the other day, used to carry it and a module with me in the glove box.

 

[Tim PloughNman Daley]

I recently put a Pertronix 91247 Pertronix Ignitor II in my 12v '49 front mount dizzy 8N w/ original coil. It never did anything but sputter on trying to start. Today I finally pulled it back off to bench test it and I'm getting no voltage at all, at any point in the rotation of the shaft.

I've hooked it up like this and double checked my connections and made sure nothing wasn't touching that shouldn't be. Igniter sleeve was still in the dizzy base. The magnet sleeve I assumed to be the aluminum plate everything is connected to - that's what it looks like to me below:

View attachment 61224


Is there anything I should check before assuming it's a bad module?


edit: I should have added that when checking for spark before pulling it off, only one of four had a decent, constant spark across 1/4" gap. 2 had no spark at all, and another had a weak spark occasionally. Battery was checked good

Yet another reason not to muck with EI. One false move and the system is toast. I have no need nor desire. I can tune up and time a front, side, or backwards distributor in my sleep.

But, your issue is likely in the distribuitor. Get a verified 12V coil to start with. Contact PERTRONIX for tech support if they even have any.

Tim Daley (MI)