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Thu Sep 09, 2021 1:44 pm

Hey all, long time no see. My current project on the Beetle is installing electronic ignition with a Pertronix distributor. In the process I noticed that the firing order on the current distributor is completely opposite of what the diagrams show ( #1 is where #3 should be, # 2 is where #4 should be). It runs fine in this order but why is it like this?

Thu Sep 09, 2021 1:52 pm

The engine firing order is 1-4-3-2 clockwise and that doesn't change.

Don't get confused with the spark plug wire location on the distributor cap. Once you have located #1, the wires go 1-4-3-2 clockwise.

Thu Sep 09, 2021 2:11 pm

Glenn wrote: The engine firing order is 1-4-3-2 clockwise and that doesn't change.

Don't get confused with the spark plug wire location on the distributor cap. Once you have located #1, the wires go 1-4-3-2 clockwise. Thanks. Any idea why the distributor is aligned completely opposite of what the diagrams show?
This is what I’ve got….(looking from back to front)

Thu Sep 09, 2021 2:15 pm

Yes, the driveshaft that spins the distributor has 11 teeth, so it's off a few teeth. This doesn't matter as long as you can turn the distributor body when setting the ignition timing.

Thu Sep 09, 2021 2:20 pm

Alright. That helps me a lot. As usual, Thanks for the info!

Mon Sep 27, 2021 3:59 pm

Ok so I’m back at this project. Can someone tell me what these wires are for? Particularly the fused one. The pos. side of the coil only has 3 prongs but I have 4 wires including the one from the new distributor. The opened up the fused link on the fused wire & the fuse was blown. I traced that particular wire & it connect s to something in what looks like the front of the transmission.

Mon Sep 27, 2021 4:08 pm

The blue wire goes fro the choke and idle cut off to the positive side of the coil.

The fussed wire 8s for the reverse lights and also goes to the positive side of the coil.

The thicker black wire from the wiring harness is the keyed positive and goes to the positive side of the coil.

The wires from the pertronix, black to coil negative and red to coil positive

Mon Sep 27, 2021 4:25 pm

Thanks Glenn. Since there’s only 3 terminals on the positive side of the coil & I have 4 wires is it safe to splice any 2 of those wires together?

Mon Sep 27, 2021 4:45 pm

You want the idle cutoff and choke on the same wire.

If the drive on the bottom of the distributor is installed backwards, it will move the wires 180*

You can remove the distributor, use a pick and take the circle spring off, and use a drift to remove the drive ears. Spin it 180* and reinstall.

But really it doesn't matter as long as the wires are in the right order starting at the compression stroke on #1. It only makes a difference if you have a vacuum advance distributor and it's hitting the case.

Mon Sep 27, 2021 4:52 pm

Hammerhead69 wrote: Thanks Glenn. Since there’s only 3 terminals on the positive side of the coil & I have 4 wires is it safe to splice any 2 of those wires together?
Better to use something like this:

Mon Sep 27, 2021 5:27 pm

That works.

Tue Oct 05, 2021 3:06 pm

Ok. So I got the new Bosch coil & the Pertronix distributor in. I then got the timing in range using the test light method. We got it started yesterday but it wouldn’t idle & it was randomly dropping a cylinder & now it won’t start at all. I pulled a plug to see if it was getting fire & now I’m completely baffled. When the key is turned from “off to on” without actually turning the engine over the plug will spark but when the engine is turned over there’s no spark. Has anybody ever seen anything like that?

Tue Oct 05, 2021 4:48 pm

Give Speedy Jim's page on troubleshooting engine start up a read: http://www.speedyjim.net/htm/eng_strt.htm
Remove all four spark plug wires from the distributor cap and follow the steps in the section "The test" to identify where #1 plug wire goes on the cap. Install the remaining wires CW around the cap in the order 1-4-3-2.

Oh, and replace the distributor cap with a solid colored one and not the cheap see-thru type.

Tue Oct 05, 2021 5:15 pm

ashman40 wrote:

Oh, and replace the distributor cap with a solid colored one and not the cheap see-thru type. Thanks for the link, I’ll check it out. As far as the cap goes, I replaced the entire distributor & cap with the Pertronix electronic ignition setup, & that’s when my problem started.

Tue Oct 05, 2021 5:18 pm

Hammerhead69 wrote: As far as the cap goes, I replaced the entire distributor & cap with the Pertronix electronic ignition setup, & that’s when my problem started.
Another endorsement for Pertronix :roll:

Tue Oct 05, 2021 5:19 pm

Hammerhead69 wrote: I replaced the entire distributor & cap with the Pertronix electronic ignition setup, & that’s when my problem started.

i have heard this scenario before !!!!

Wed Oct 06, 2021 7:31 am

Make sure the pos. side of coil is getting 12 volts as the electronic "points" don't like lower voltage.

Wed Oct 06, 2021 7:46 am

Hammerhead69 wrote: When the key is turned from “off to on” without actually turning the engine over the plug will spark but when the engine is turned over there’s no spark. Has anybody ever seen anything like that?
Check this...
Remove center wire from distributor cap and hold it near ground (2mm) so you can confirm ignition coil is sending a spark.

With the ignition ON, rotate the crank pulley by hand and watch for a (blue-white) spark to jump the gap from the wire end to ground as the rotor passes each of the four posts positions in the distributor cap. Rock the crank back and forth around the point where the spark fires and it should throw a spark each time the electronic points trigger the coil to spark. Repeat for each post on the cap. This confirms the electronic points are triggering the coil to spark as the rotor passes each of the posts.

Have someone crank the engine while you still hold the coil wire near ground and you should see the coil sparking at regular intervals. A starter bump switch is a big aid if you are by yourself. Odd spark intervals while cranking means one or more cylinders are not firing and you have a problem with the electronic points and its magnetic pickup.

If there is no spark from the coil wire while cranking... measure the voltage at the #15 (+) terminal of the ignition coil while the engine is not cranking and while it is cranking. You should see a voltage drop while cranking but if the voltage drops below 11.0v while cranking it will likely result in the electronic points no longer working. This is a common problem with old wiring creating high resistance such that insufficient current makes it to the coil/points.

To confirm it is a problem with voltage reaching the coil... run a wire from the battery positive post (use your battery jumper cables) and power the coil #15 directly from the battery. This is the highest voltage you can get. Test the voltage while cranking. If it still drops below 11.0v it means you have a weak/old battery (or a starter that is drawing too much current away from the battery). If powering the coil from the battery allows the coil to spark, reconnect everything and try to start the engine while the coil is powered by the battery. If you get the engine running when the coil is powered directly from the battery you know the no spark while cranking was caused by lack of current making it to the coil.