Reinstalling Ignition Points 2.7 CIS - Tuneup Gone Bad

[94teener]

Hi all - in the course of tuning up my '77 911S the Pertronix magnet donut came apart when I pulled the rotor off the dizzy. The 6 little magnets fell out because the donut upper actually separated from the bottom portion. I have run the Pert. unit for probably about 10 years now so it did last for a good while. I attempted to super glue them back in but eventually just bought a new donut. Before I noticed this however, I had put the rotor back on, buttoned it up and attempted to start the car - when it didn't start that is when I noticed and found the six magnets all stuck to the dist. shaft - I do not see any apparent damage done to the distributor anywhere.

Ever since that time, after the tune-up (very simple tune-up, plugs, valve adjust, dist. rotor and cap, oil, oil filter, air filter, timing check, idle adjust - done it many times) the car has run worse than ever. Typical CIS complaints - poor starting (revs way up to 3000 whether hot or cold), lots of backfiring (thank goodness for pop-up valve), difficulty idling smoothly. The car accelerates and runs at speed just fine. There is a very distinct tinny pop-backfire that sounds like it is coming from the center of the engine - as well as lots of backfiring thru the pop-up valve - stumbling and all sorts of bad things when it attempts to idle and air screw adjustment does not help.

The symptoms remind me almost exactly of when the brake booster vacuum hose that comes off the engine was cracked - it took me several years to figure that one out - but along with the poor running conditions produced by that vacuum leak the brake booster was also not working - but I didn't have the knowledge/experience to put 2 and 2 together - my local wrench had to solve that one and when I got it back it was like heaven to have the car idle properly.

This time it runs even worse than that - but the brakes have plenty of pressure.
So, obviously I have attempted to look at all the hoses that I know about and can see - I don't see any cracked or loose hoses anywhere, nor did I unattach anything.

I have adjusted the timing every which way - a little BTDC (this model is timed at Z1 according to the manual) - and also at the 5 ATDC mark - but that didn't seem to change the overall condition. At 6000 or so the timing checks out on the 35 BTDC mark okay - but the manual does not specify checking advance for this model. And yes, on this model the vacuum can is plugged as is the little vacuum line.

Since the only thing that really changed was the magnet donut I thought I might try going back to points at least for a quick try - but after installing the points the car is not starting at all. Whilst the dist was removed I noticed the wires to the dist. were all funky and fragile - barely held together by a few strands - this is the coax wire that splits off into 2 wires - I spliced a nice new wire to the outer coax - and ran that end to ground on the chain case cover. Spliced a nice new wire to the center of the coax and attached that to the points male connector that comes thru the dist. body. I can tell this is not right - or I am missing something - the car acts really weird - like it will try to turn over just for a second when I switch the ignition off.

I searched this forum for a couple of hours for a diagram or explanation of this wiring but unfortunately am not finding what I need - and the manuals don't seem to be much help as the Haynes and even the factory manuals are very skimpy on dist. info. Problem is - I really don't see any other way of wiring it. Points gap is set at .012 as per the specs.

Since the car DID run with the Pertronix Ignitor (albeit not very well) - does that indicate all is well with the unit? Or can it still be doing something funky like missing, etc?

Please can someone help set me right on the original dist. wiring so I can eliminate this possibility? Other input appreciated as well. I feel strongly it is most like a vacuum leak - but where?

Thank you in advance.