XJS Ignition pick up

(Poppa) #1

Hi All,
Have a question about the distributor ignition pick up module. Just replaced mine and was just finishing off the job and went to plug in the lead for the amplifier and noticed the polarity on the plug is opposite from the old one.
This unit was bought as an original part (have my doubts about that too!) and the plug can only go one way, does anyone have any experiance of this job.
1988 v12

cheers all

(Greg) #2

I went through the exact same problem last month. I created a connector to reverse polarity, and it ran worse, very very advanced. If you look at the two pick ups, the same wire that connects to the male plug goes to the same part of the pickup. My guess is they messed up the wire color.

There is a huge conversation about it buried halfway in my thread about my engine “running rich, I’m at a wall after two months”

And I don’t think you can get original part anymore. I ordered from a Jaguar dealer, and the bag said SNG Barrett.

You would actually help verify…was your engine running fine before? Is it still running ok with the new pickup?

(Poppa) #3

thanks for the reply gregma, engine was running ok but had a “miss”, not just a one cylinder miss but whole engine would “die” for a millisecond. Got less noticable when engine got warmer. So far have replaced plugs, leads amplifier, coil and now pick up. I did notice that the male part of the multi-plug has a + written on it (red wire) so that doesn’t agree with these units being wrongly wired.
Further I bought this as an original, in fact paid a lot more than the “replacement” part but doesn’t look like my unit I took out. Me thinks I have been duped…
Will phone the supplier tomorrow and see what they say

(Greg) #4

I paid $130, that’s the going price of aftermarkets. I did notice that the metal circular frame was of cheaper quality, and in fact, didn’t fit perfectly, so I couldn’t get it exactly level. Ended up using original oem metal frame with new pickup coil/wires transplanted in.

(Poppa) #5

I paid £150 for a so called original replacement, thinking this was worth the extra, not so , still had to slightly bend the locating pins to make it fit. Anyway, did you manage to make it work properly eventually?
what would happen if I plugged in the connector as is (opposite polarity) would it blow the amp or fuse anything??
thanks again for the advice gregma!

(Greg) #6

Yeah, I bet the original quality manufactured one is NLA. You probably have a decent aftermarket like mine. It’s a simple coil, why so expensive? They tend to not go bad, I found most people on forum still had originals. If it plugs in backwards, the trigger wave just reads backwards, no problems other than timing issues.
Again, read halfway through my marathon post a few weeks ago, a lot of experts including Kirby chimed in about it.

(Poppa) #7

thanks for that gregma. just a quick update. I contacted the supplier (not sure if I’m allowed to mention who) they agreed that this ignition pick up has been badly manufactured with the wiring reversed. They are contacting Jaguar to find out the true story. Probably been made in China…
Once they get an answer they will sort something out. Not sure if this helps as it sound like you were right about being NLA, what do I do then as I’m fairly sure the original one is faulty?

(Greg) #8

I’m still betting that the actual wires are correct, except that they got the red/black colors reversed. Meaning, the black is actually the positive, and the red is actually the negative.

The actual pickup part is just a simple coil and magnet, pretty hard to mess that up. Same with the wires and the plug.

The metal part is where I see cheapness. Inferior metal, and not machined perfectly to fit.

Only reason it’s expensive, I guess, is that it only fits Lucas distributors on Jag HE V12s? Not a lot of demand.