Dizzy question

bowlsby · 07-07-2000, 02:16 PM

Stock 74 2.0 914 with FI

I recently pulled the distributor to install the Crane XR700 and new FI points. While cleaning things up, I noticed that the copper braid connecting the 2 stacked breaker plates was missing, (thank you PO)although their connection points still existed on each plate. I fortunately had a back-up dizzy, which had the plates with the braid intact, which I promptly installed into my original dizzy.

I've had the car for 2 years and the engine has worked fine without the braid. My car won't start now, but I need to review everything related to the XR700 install again.

Is the braid needed, and what is its purpose?

S Schroeder · 07-07-2000, 02:24 PM

That is the ground. I had one side of that wire come loose and wreak havoc for a week before I found it. Once I replaced it, all was great. Bummer that the car won't start now that it's "fixed". Hopefully it's just a misplaced wire on your electronic ignition.
Good Luck-
Scott S

djs · 07-07-2000, 05:41 PM

I have this same setup in my '75 2.0. Although my copper ground wire inside the dist. never broke, I can comment on the Crane installation.

The XR700 unit has a wire on it that is meant to be grounded. I simply attached it to the negative side of the battery, since the XR700 itself was screwed to the firewall. If you are assuming that simply screwing the case to metal is grounding it, that may be your trouble.

Also, if you have grounded it properly and it still won't work, make sure that you have followed the instructions for aligning the LED pickup with the 4-slot plastic aperture. Note that when you have followed the instructions, you may find that the distributor now needs to be turned slightly from its original position, necessitating that you re-time the motor (27 deg. @ 3500 rpm).

I recall that I needed to do this after switching from points to XR700. The LED aperature may not be position on the distributor cam exactly where the points were.

But when you get it all dialed in, you won't regret the effort. I have run an XR700 now for about 3 years with absolutely no problems. My timing never varies and my car starts on the first turn of the key every time. Definitely a worthwhile upgrade!

Hope this helps.

Dan

Jim Smolka · 07-07-2000, 05:58 PM

You can fix your old Dizzy copper braid if you like. If the copper is broken in the middle, solder a new piece of braid to connect the two end pieces.
Where to get the copper braid you ask???

Go to radio shack, buy a small role of solder wick (solder removing stuff), solder, and container of solder flux.

Tin the two ends on the dizzy braid with flux and solder. Hold old braid with needle nose solder in such a manner that to ack as a heat sink to prevent the solder from wicking up from the end of the old braid.

Tin new braid. Solder new braid. Be sure to use needle nose on old braid to prevent wicking (has to stay flexible).

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Smoke Daddy

bowlsby · 07-10-2000, 12:53 PM

Thanks for the helpful replies...I'm chasing the appaent electrical problem now...I hope I haven't fried anything...

I am puzzled about the missing ground braid from my original dizzy. The car ran ok for the 2 years I've had it, without the ground!

I can't figure out why the car would run at all without it...any ideas?

jmcleod · 07-10-2000, 02:05 PM

interesting, just today i installed a pertronix system in my 74 2.0. i had an extra dist. so i disassembled and cleaned it, checked the vacuum ablility of the advance "thingy", noticed the broken braided wire but figured if it's a ground, the plates are already in contact so i didn't solder it back up. it started ok and i adjusted the timing. (how do you hold the throttle at 3500, pull the trigger of the timing light and turn the dist. all at the same time?). took it out for a test run and it seemed to run better, will hold judgement until after some more driving. it did require me to adjust the idle speed up and previously i had reached the limit of the idle speed adjustment and couldn't get any lower. now i seem to have some adjustment left. now my question is about reading the plugs to see if the mixture is ok. guess i'll have to build one of those O2 sensor mixture indicators as i can't keep going to the mechanics shop.