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MG TD TF 1500 - Pertronix ?

Friend of mine just recieved a pertronix for his 51 TD. (possitive ground car)
The question is:
Is something missing here?
This is all they sent him.


David Sheward 55 TF1500 # 7427

I know that the unit for my TF (negative ground car) came with a "collar" that goes on the shaft under the rotor. I was under the impression this was needed to "read" the impulse from.
Is this something new, so it no longer requires this...or did they short him a piece?


David Sheward 55 TF1500 # 7427

He got shorted...need the collar..it has 4 magnetic rods that trigger the firing.
L E D LaVerne

LaVerne's got it right. When your friend gets the right parts, I'd suggest that he might take a look at http://www.ttalk.info/Tech/PerPosGndWiring.htm before he starts installing it. There's a tendancy for folks to just green thumb the installation the way they would a negative ground unit. Bud
Bud Krueger

Kind of what I figured. They are telling him something different. My hope is he can kind of prove to them that is the case.
Thanks Bud allready pointed him that direction!
David Sheward 55 TF1500 # 7427

LED and Dave are right on! The collar has to be coordinated with the type of cam you have in the distributor and the pickup has to be matched with the ground polarity.
Jim Merz

Keep the OEM points & condenser, you will need them!
And the tools to install the factory parts on the road!
Len Fanelli

Len ,
My advise was the same. I keep my OEM in the boot, however it has only been "out" once in 10+ years. That was as a loaner for another car to get him home.
(He was not running a Pertronix.)
David Sheward 55 TF1500 # 7427

I might have a spare in my box Dave if it doesn't work out Dave. You can keep the points in the tool box but you better keep a test light and a wrench in there also. Switching it back to points requires re-timing because of the funky way the positive ground pertronix works...been there done that. Same when installing one. Let him know that its "firing" when the test light is out and not lit as it would be for a point system.
L E D LaVerne

I've heard more pertronics users continue to keep their old points plate as a spare and a couple that have even had to employ it for their or another's failed pertronics. Get the points that Jeff at Advanced distributors sells and put a points file in your tool kit... Fully road servicable!

Alex
Alex Waugh

I carry an extra Pertronix sender unit. Makes mkore sence, but a bit more expensive. But this hobby isnt cheap anyway is it?

regards,

Jan
Jan Kristoffersen

Does anybody see anyway this would work?
http://pertronix.shptron.com/p/ignitor-lucas-4-cyl-12v-pos-gnd

Makes no sence to me!
But this is what they "show" and what they sent!
David Sheward 55 TF1500 # 7427

I can't see this working. Without a collar the sensor would have to recognize the bump in the distributor shaft that moves the point. Theoretically possible with a proximity sensor but much too inaccurate to work

Mike
Mike Fritsch

Learn something new every day ...this just in from Pertronix:

"The LU-146LSP12 is a lobe sensor kit, which means that the module triggers off the lobes of the cam rather than a magnetic sleeve/collar.
You are not missing parts. The older kit, LU-146 did come with a magnetic sleeve.
If you would like to speak to our technical department you may contact them at 909 547-9058
Thank you,
Customer Service
PerTronix, Inc."
David Sheward 55 TF1500 # 7427

They are describing it as a "lobe sensor". To me that says that Mike is right, it's not a Hall effect device, it's a proximity sensor. I suspect that it would be very sensitive to wobble in the distributor shaft. Bud
Bud Krueger

Definatly a different unit. Notice the base is a horse shoe shape while the other one is a full circle and mounts as the points plate does. Looks like it will retain the original points plate for mounting...just guessing.
L E D LaVerne

Maybe I'm crazy ...but seems to me this is going to be a lot harder to set-up correctly.
(Possibility of 3 different "lobes" in our cars makes me wonder if still sold specfic for this.)
I wonder if all of them are being made this way now?

I have a spare set-up (plate,points,condenser) I carry along with circuit tester (as well as throw a timming light w/advance in there for longer trips).
Think I will continue to do so.

Kind of wish I had purchased a spare pertronix 10 years ago. Too many times I have seen a great product go into "mass-production" and end up not quite being "up to spec" of the orginial!
David Sheward 55 TF1500 # 7427

Was just in the shop and had a look at some points. Looks like this thing takes the place of the points on the original plate. No possibility of adjustment..it either works or it doesn't. Wonder if the wiring is still as funky for the positive ground?
L E D LaVerne

Well, it seems I stand corrected as far as the accuracy is concerned - if they got this to work, it is an impressive piece of technology !

But I agree with Bud, it is probably sensitive to wobble in the distributor shaft (my "deduction" would be that with a point, the shaft will get under tension when it opens the point so it will have no wobble as long as the point is engaged. Without any point, it can wobble freely in any direction..)

Mike
Mike Fritsch

Mike I actually put a Pertronix in a 6 cylinder Continental fork lift engine a few years back because the dissy was so worn that the points would only open intermitently. It was a collar type trigger and apparently isn't that sensitive to the distance. It has kept the seldom used Hyster running to this day. Thing needs a complete rebuild but there isn't any money in the budget for it.
L E D LaVerne

La Verne, I do believe the collar type would be robust, even more than the point, since it has an active trigger element that produces a strong signal
Not so sure about a proximity sensor, though, but maybe they got it to work fine...

Rgds, Mike
Mike Fritsch

This thread was discussed between 28/11/2012 and 04/12/2012

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.