Pertronix failure...

Yes, infant mortality, as we say in the maintenance trade.

Been reworking an old ('86) Four Winns and it's 170 Mercruiser. New interior, Smart-tabs, new charging system (Hunn-Finn conversion to a Delco alternator), and Pertronix ignition to replace the breaker points.

Finally got her out today to test everything and found:

1. The charging system worked fine - 13 to 14 volts all day.
2. The Smart-tabs were a big improvement, as I could plane in less time and at lower throttle, and didn't have to zig-zag at low throttle.
3. The interior upgrades (New seats, motor cover, etc.) impressed the lady, which is a BIG advantage in numerous ways...!
4. My Pertronix pooped out.

Been starting her in the driveway (muffs) for about six weeks to check all my upgrades and the ignition system showed no signs of malfunction. But today I got her under load for the first time and:

1. As I approached 4000 RPM, she began to bog - run-stop-run-stop.
2. I throttled back and this reduced, but then began to occur at lower RPMs.
3. Soon I was unable to accelerate, as she backfired and chugged whenever I pressed the throttle.
4. Finally I tried to bring her down to an idle, but she stalled as I did so, and would not start.
5. Checked for fuel in the carb (it was there).
6. Had the lady work the ignition key and checked for spark at the no. 1 plug wire (it wasn't there).
5. Replaced the new "Flame-Thrower" coil with the original, which I had aboard as a safety measure. -- No help.
6. Pulled the "Igniter II" ignition module and magnet out and reinstalled the original breaker plate with the original points and condenser. She started right up and ran the rest of the afternoon without incident.

I was fortunate that the weather was good, that someone in this forum had suggested keeping the old stuff in the boat when first running new stuff (and that I had seen the post!), and that the lady was patient.

I'll be in touch with the vendor tomorrow regarding a replacement.

Thought you might be interested.

Re: Pertronix failure...

I would leave the points in there.

Re: Pertronix failure...

I actually just replaced my Mercruiser 170's points with the Ignitor II and Flamethrower coil. The directions does a bad job explaining this but the old coil doesn't have an internal resistor, so you either have a ballast resistor or resistor wire on the outside of the coil. Mine had two wires: purple w/ yellow stripe, and plain purple. The plain purple was the resistor wire.

What you have to do is remove that resistance wire because it only supplies about 6-8v to the Ignitor module. The module needs a full 12v to run properly. Run a 16g stranded wire from your ignition switch back to the motor at attach to the positive side of the coil, along with the purple yellow striped wire, and the red positve wire from the electronic module.

The Flamethower I/II coils have an internal resistor, hence the need for discarding the external resistance and providing a good, full 12v.

I DIDN'T run a dedicated wire at firstand had to paddle from the middle of the lake and pull the boat on nearly a mile long shoreline and push the boat on the trailer. The plugs weren't firing right causing my engine to flood and not restart.

I fixed the issue with the above mentioned intervention and wallah, all is well now!

It really is a great system. Get some 8mm plug wires, new high end plugs. I've got mine gapped at .040" with the Flamethrower I coil. They say with the Flamethower II coil you can regap up to .045".

Keep the Ignitor on there and never mess with points, dwell, or condensors again.

Re: Pertronix failure...

If all that is correct, you should be able to just replace the purple (resistance) wire, with a regular stranded wire.

Re: Pertronix failure...

Typical Pertronix...I have now removed more defective ones than I have installed as I don't recommend them anymore. What a half-baked POS. Keep the points, save a tow!

Re: Pertronix failure...

zbnutcase said:

Typical Pertronix...I have now removed more defective ones than I have installed as I don't recommend them anymore. What a half-baked POS. Keep the points, save a tow!

Click to expand...

Yeah never did get mine to work right, put the points back in, kept the Flamethrower coil thought, really like that.

Re: Pertronix failure...

Is the Petronix the same as the Siera Conversion kit?
I have a Merc 140 3.0 that I just put the Siera kit on.
I have not taken the boat out and did not modify the resistor wire either.
The way I read the instructions were that if you had the Ballast resistor then you have to change the wire.
I will definately keep the old stuff in the boat just in case.

Re: Pertronix failure...

I agree with stonyloam, you should just be able to remove the resistor wire and crimp in a new non-ballast wire in it's place to get the 12V. Also, there isn't anything wrong with the Pertronix units, or any other electronic conversion kit if they're installed correctly.

Re: Pertronix failure...

I guess I've been lucky I replaced my points with a pertronix(89 omc 3 ltr).I've put on over 80 hrs no problems.I do keep the points in the boat just in case.

Re: Pertronix failure...

zbnutcase said:

Typical Pertronix...I have now removed more defective ones than I have installed as I don't recommend them anymore. What a half-baked POS. Keep the points, save a tow!

Click to expand...

Well of course, if you're a boat mechanic nobody is going to bring you a properly working unit, right?

Just kidding, anyways to each their own, some people have decent luck some people have bad luck..

Re: Pertronix failure...

jgoeden said:

Well of course, if you're a boat mechanic nobody is going to bring you a properly working unit, right?

Just kidding, anyways to each their own, some people have decent luck some people have bad luck..

Click to expand...

Well said. It's like hearing a GM mechanic talk about how many Chevys he sees with problems . . . rarely does a person bring in a perfect running vehicle just for an inspection by a mechanic. If Pertronix were that bad, they wouldn't be in business this long.

Re: Pertronix failure...

Good comments everyone.

I contacted the vendor and told him the story. He said that the ground connection is always suspect in cases like this - that anything over .2 ohm from coil negative to battery ground may be a cause of poor operation. And, of course, he recommended replacement of the resistance wire to the positive of the coil. (And he said that if I shipped it back he'd "check it for proper operation", whatever the h_ll that means.)

Couldn't get out to it today, but tomorrow I'm going to:

1. Measure the resistance from coil negative to engine ground with a digital ohmmeter. (Just so I know...!)
2. Regardless of the result, I'll run a new, external ground from coil negative to the battery negative.
3. Run an 18 gauge machine tool wire from the ignition switch to coil positive.

These steps remove the elements he indicated could reduce Pertronix performance.

And:

4. I'm going to send it back so that he can "check it for proper operation". (I emphasize that there was NO SPARK when I tried to restart the engine. Not a weak or erratic spark - NONE!)

I too believe in electronic ignition, and have no reason to doubt the Pertronix. I think I simply got the one in a thousand that fails in service.

I'll repost the results of all this here.

Thanks for the interest.

Re: Pertronix failure...

generator12 said:

Good comments everyone.

I contacted the vendor and told him the story. He said that the ground connection is always suspect in cases like this - that anything over .2 ohm from coil negative to battery ground may be a cause of poor operation.

Click to expand...

That sure doesn't sound right. The negative side of the coil only goes to ground when the pertronix unit activates and provides a path to ground. You sure he didn't mean the ground connection from the pertronix unit to ground?

Re: Pertronix failure...

Whoops! I mis-spoke. Yes, the grounding of the plate, distributor housing, etc.

Thanks for correcting me.

Re: Pertronix failure...

I think the rep meant that he would check the unit you have to verify it is still operating correctly. I'm sure they have specialized equipment to diagnose a faulty unit pretty quickly. If it's broken, he'll issue you a new unit, if it is operating correctly, you may just need to get the wiring figured out.

Re: Pertronix failure...

oh yeah points are awesome (insert sarcasm here) thats why GM,Ford,Chrysler and every other manufacture still us them (again more sarcasm). The marine industry realy needs to get out of the 70's when it comes to inboards!!
From experiance, conversion kit failures are generally caused by installer errors with the ocasional bad item leaving the factory. Gotta love mechanics that always blame the part for there lack of troubleshooting ability.

Re: Pertronix failure...

Shamus O'toole said:

oh yeah points are awesome (insert sarcasm here) thats why GM,Ford,Chrysler and every other manufacture still us them (again more sarcasm).

Click to expand...

And GM, Ford and Chrysler use Pertronix units...NOT(even more sarcasm)

Shamus O'toole said:

The marine industry realy needs to get out of the 70's when it comes to inboards!!

Click to expand...

In case you haven't noticed, There haven't been points in marine engines since the very early 90s. The difference though is that they use electronic ignition distributors that are more reliable than these Pertronix units.

Re: Pertronix failure...

bruceb58 said:

And GM, Ford and Chrysler use Pertronix units...NOT(even more sarcasm)



In case you haven't noticed, There haven't been points in marine engines since the very early 90s. The difference though is that they use electronic ignition distributors that are more reliable than these Pertronix units.

Click to expand...

and the GM HEI dizzy came out in the late 70's and the marine industry used pionts until the 90's....hows that for being up on new technology! I'm not saying points conversions are the newest best deal on the market. But it's ****load better then points. If installed properly. magnetic pickups DO NOT wear out.


Modern engines don't even use dissy's anymore. How many boat manufactures are using coil on plug technoology? How many high dollar modern boats are using GM LS motors, Ford overhead cam motors...??? again the marine industry needs to get the the program when it comes to inboards. Lets not even get into the newer more modern diesels. With the current cost on a new boat you are getting outdated inboard technology at a high premium cost.....end of story.

Re: Pertronix failure...

Nice..changing the subject. The subject is the reliability of Pertronix vs points. Stick with the points vs Pertronix or go with a real electronic distributor like the Delco EST.

The other stuff is all trade offs of cost vs reliability vs performance. Certain automotive applications just are not feasible in marine applications.

Re: Pertronix failure...

bruceb58 said:

Nice..changing the subject. The subject is the reliability of Pertronix vs points. Stick with the points vs Pertronix or go with a real electronic distributor like the Delco EST.

The other stuff is all trade offs of cost vs reliability vs performance. Certain automotive applications just are not feasible in marine applications.

Click to expand...

pionts wear out.....magnetic pick-ups (ie. pertronix,MSD) don't wear out. If it was me I would replace that old school distributor with a more modern dizzy. But thats just me..