Green "dizzy" wire replacement help@

[Hawks911]

First "dead on the road" experience with our '78 SC last weekend. Got it started again and was able to keep it running if I kept the revs high. Had a few "rolling restarts" and a rather exciting ride home with the wife on the edge of her seat! Great way to bond with the 911.

Turned out to be the short green distributor signal cable pigtail. PO had a failure of the male plastic connector housing, which was completely missing from his pigtail! The two loose metal male pins were just pushed into the female connector with no clips, tape or anything. I had just taken the car on a three hour road trip the previous weekend. Fortunately, this trouble showed up only a block from home.

Ordered a new pigtail from our host - $$, but looks to be a well made Bosch harness. Thought it would be a 5 minute install untill I realized that the distributor end connector looks to be held in place by a metal clip, held in place by a small screw, of course on the back side of the distributor. Picture here of another Pelican's distributor with the new pig tail installed.



Looks like it will be a bear to get the screw out without clearing out an oil line or two, rotating or pulling the distributor.

Am I missing something here? Any tips appreciated.

Thanks.

Mike

[j_mancini]

Hi Mike, it was pretty easy to pull the distributor to get at that clip on my SC. Just set the motor to TBD (Z1 mark on the pulley). Then make an alignment mark (I used a black magic marker) at the base of the distrib, pull off the cap, unbolt the distrib and pull it out. Install is reverse...

[onboost]

+ 1 on above procedure

Just replaced the same on a 78 SC two weeks ago..

Paul

[john walker's workshop]

mark both the distributor base to engine case and where the rotor is pointing. there's a notch on the top edge of the distributor body for #1 TDC position. you can also scribe around the hold-down washer and return it to that position to keep the timing virtually unchanged.

[Gunter]

JW said it.
When you have the pulley at the Z1 mark, open the cap and make sure that the rotor points to the little notch on the edge of the distributor indicating combustion stroke for #1 cylinder.
If the rotor points to the opposite side, turn the engine one more rotation to Z1.
To turn the engine, use a big socket on the Fan-pulley, squeeze the V-belt withe the other hand to prevent slippage.
I find it easiest to get the distributor out by using the U-side of a small pry-bar and applying leverage from underneath.
Also, do you have the special plug needed to complete the connection with the pig tail?
Some soldering is required.
DO NOT mix the signal wire with the ground wire inside the cable when making the splice.

[fredmeister]

Gunter brings up a great point.....you need to be aware that the green wire is a coaxial cable and making the splice if that is what you are gonna do is tricky. Otherwise the cable will not function.

[Hawks911]

Gents,

Thanks for the prompt feedback. This support community is awesome. On my '78, I have a connector in place in the main harness that should receive the connector from the short pigtail. I may decide to rebuild that female connector, on the harness side, to address the damage that comes from 30 years of heat and vibration. Just wasn't sure about the best method to get the connector off of the distributor. Your advice has given me the courage to remove the distributor and get better access to the connector.

When I did my first complete rebuild of an engine 26 years ago on my first real car ('72 Monte Carlo with 350 Small Block), the only problem I had was the re-installation of the distributor (off be a few teeth). When I corrected that, the engine ran fine for another 30,000 miles, until I sold the car to my brother-in-law.

I guess I'm just distributor-averse, due to the psychological damage. This will be helpful therapy to work through the deep wounds of my childhood.

Thanks again.

Mike

[Hawks911]

It's alive!

Armed with the advice of the above Pelican advisory board members, tore into the distributor removal, green wire replacement, distributor reinstal and most importantly, the attempted restart.

Took a few pictures for those that may follow....

As is condition, with "patched wire with only 1/2 of a connector...











The fan shroud / crank pulley markings lined up at TDC (Top Dead Center)...




Sharpie markings on the distributor orientation for reassemble at same timing condition...



Orientation of rotor at first attempt at TDC (out of phase 180 degrees)...



Orientation of rotor at second attempt at TDC with rotor aligned with mark / notch on distributor...



Distributor removed with the culprit pigtail clip...





More pics in next post

[Hawks911]

Distributor with new pigtail installed...



Gratuitous pic of the interior of the wonder motor...



Distributor reinstalled (note missing wire bail to mechanically lock the connector and poor state of boot and wire on harness end of the connection...



Temporary "patch" with electrical tape to hold connectors together until I can rebuild harness end with new connector and leads...





Best news is that it roared to life on the first crank. I've fought the distributor demon and won!

Many thanks to all who helped with their advice.

Mike

[Gunter]

Mike:
It looks to me that this distributor could use some internal TLC.
For an easy DIY clean and lube, go here:

Distributor service (Clean and lube) real easy without removing the pinion gear!

Also, don't assume that the timing was correct in the first place.
Buy a nice strobe light and check. (The 12 connection is on the rear fuse panel)
5 deg at idle 950 RPM - steady advance throughout increased RPM to 30 deg at 6000 RPM.
With the help of a caliper, make a notch/mark at 30mm on the pulley.
Z1 is 0, the 5deg mark is 5mm, measure 30mm from Z1 and mark.
With the white paint mark on 5- and 30deg, you'll see the range with the strobe light.
Protect the new green wire with an extra tubing.
You can buy these protective tubings in various sizes; I use them on all wires/cables and don't allow them to touch anything with heat.

[Hawks911]

Gunter,

Thanks for the tip. My first focus was to get the distributor out and back with the new cable and at the same position as before. I have a good induction timing light that I used for the '72 Monte Carlo, in it's day. Will check the timing per your instructions. Liked your well documented procedure on the refurbishing of the distributor internals. That's on the list of next steps. Looks like a worthwhile project that gives me a chance to use those circlip pliers that I use once every five years!

Good idea also on the protective sleeves. Will keep an eye out for a local source.

You're awesome!

Thanks again.

Mike

[fredmeister]

Congrats you just saved yourself $200 or more by doing it yourself......Porsche dealers get $100 per hour or more around here. That pays for alot of engine mods......
You might want to seal the openings in the sheet metal by the distributor as well. This acts as a barrier to letting the cooling fan pull warm air from under the sheet metal into the engine compartment.

[Gunter]

Yeah, plug those holes.
Looking at the big hole: How are the heater ducts routed through the tin on that side?
The ignition cables look "Well used"
Time for a new ignition harness?
Check this:
The Beru plug connectors should show ~3k OHMS
The cap connectors are 1k OHMS.
Check each wire from end to end: ~4 OHMS total resistance; anything else means a problem.
If you get/make a new set, you don't need the type with steel sheeting, it's just a ground.

[Hawks911]

One step forward, two steps back! You guys are real task masters. The big hole is from the air pump that was on the car for California emissions, back in '78. It was removed by a previous owner, but still had a large rubber gasket that had turned rock hard due to age and heat. It rattled against the sheet metal with the engine running, so I pried it out last week.

Here's what's left of the gasket:



Appreciate the advice on plugging the holes for better engine cooling.

Gunter,

The heater hose routing, I believe, is quite stock. I replaced all of the lines and rebuilt the rear blower motor this last winter, along with replacing the flapper box control cables and the front fresh air blower motor. The heater system on this baby is one area that is up to par.

Here's a few shots of the hoses:



Gratuitous angle to reveal new engine compartment sound pad, purchased from our host, and installed last weekend:








All of the hoses were pretty straightforward to replace with the exception of the lower end of the right hand side hose which was buried by the freon compressor. The SSI's, new hoses and rebuilt blower finally resulted in my wife asking "could you please turn down the heat?" which was my ultimate objective!

Also, someone asked about the relationship of the shielded braid on the green wire versus the inside lead as they go into the connector at the distributor. I peeled back the old connector and determined that the outside coax shield is on the right side, going into the distributor, looking from above and outside the distributor.

This pic is from the top of the connector, facing into the distributor:



Thanks again to all who helped, and a special thanks to those who have added to my to do list!

Mike

[Gunter]

If you have SSI's, this is what your engine bay should look like:



NO A/C compressor, NO extra fan blower, NO cruise control:

Wonderful to work on, lot's of room

[Hawks911]

Very nice! On a '78, the rear blower is not an extra, there are no blowers in the floorboards. The most important accessory in my 911 is my sweet baboo on the seat next to me. If she needs heat, the blower stays. You have a point about the A/C. It doesn't work and doesn't seem to be worth the effort to update to new style freon. But it does get hotter in central IL than BC.

At least I don't have the cruise control deal with.

Cheers.

[RWebb]

I can't find "sweet baboo" in the Pelican parts catalog...

[Gunter]

Originally Posted by RWebb

I can't find "sweet baboo" in the Pelican parts catalog...

Yeah, same here. Maybe under accessories?

Mike:
The fan blower was added by Porsche because some of the folks who don't eat whole wheat felt that there was not enough heat when idling at a red light or being stuck in traffic.
Many people, including myself, found out that with SSI's, there was more heat than with the regular heater boxes and the blower could be eliminated; thank heavens!
So, with SSI's, and Granola for breaky, the blower can RIP.

[AngM018]

do you know what terminal on the connector is for the internal wire, and which one is the terminal for the wire that wraps around it? as you can see the notch on the connector, which is only on one side, is facing the camera.

[Hawks911]

Ang,

The pic I posted 10/13 above shows that the external coax braid is on the right hand side, going into the distributor, when viewed from the top.

Good luck.

Mike