Help!! Burned Up Engine Wire Harness

[Sunroof]

My wife and I were taking a drive last week in the 73.5T and we both smelled something funny through the vents. The alternator light came on and the car died. We towed the car to an Atlanta repair shop for what we thought was a simple alternaotr replacement, when we leared that the REAR ENGINE WIRING HARNESS has serious burn damage. From what we were told, we were fortunate that the car did not catch on fire!

So, I am now plagued with trying to locate a used or remanufactured engine wiring harness for a 1973.5T, 2.4 engine.
Where does one go? Can you rely on another 30 year old harness? The repair shop is not crazy about building a new one and the existing harness is too badly burned to repair. I suggested we just build a new one and map out the colors for any future repairs, but that would be time consuming.

If anyone can chime in and give me some advise, I would be grateful.

Thanks
Bob

[RickM]

May want to give these folks a call:

http://www.ynzyesterdaysparts.com/

or

http://www.ignition-system.com/wiring_harness-porsche-parts.html

[RickM]

From the first link

According to their site they also sell complete wiring diagrams for $5.

[304065]

Bob,

For $289, I'd make a new one. If you are going to concours I would do YNZ. You can take the middle ground and order the original german faston connectors for the engine end, and you can get the silver pins from pelican or a dealer (I used Stoddard before I found Pelican). Fabrication time a couple hours if you are good with a soldering iron and heat-shrink gun.

If you have the old harness, that's where to start. With the wiring diagram, you have the colors, so it's pretty easy.

[ChrisBennet]

Look on page 184 of May 2004 Excellence. There is an ad for "Wiring Harnesses Made in Germany" $595 including shipping, 2 week delivery.
Fax (29) 9462/2628

Since all your harness didn't burn up (just the engine harness) maybe it would be cheaper than that?
-Chris

[Sunroof]

Thanks Fellas.
So far batting ZERO on getting a new harness. YNZ has no pattern and the other site does not have anything! Porsche dealer cannot find one on the entire planet and the dismantlers are not giving me much hope either. Aside from trying to make one myself, I am running out of options. Anyone know of any other dismantlers anywhere?

Thanks
Bob

[304065]

Bob,

Even if you get one from a dismantler, it's going to have issues. The wires work-harden from vibration over the years, and the insulation turns brown and brittle. Around the silver-plated brass pins, you will find oxidation, and the pins themselves tend to spread, making a loose connection. Even if the Porsche dealer can help you, they're probably going to say that the part has been superceded.

Did ALL of the wires in your harness fuse together, or did just a couple melt together? A complete new harness may not be necessary.

[Tim Walsh]

I recreated dtw's harness from his spare 72 MFI harness in an evening. How close would a 74 harness be since the 72 and 73 MFI harnesses are the same maybe it's the same for 73.5 and 74's?

[RickM]

Give it a little time. Someone here will come up with something. Is the burnt harness totally destroyed? Know what caused the burn?

[rattlsnak]

Bob, you'll have to tow it over, but bring it to me, ill fix it for you. Call me.

[Jim Sims]

Three years ago; I ordered both sections of the 73.5T engine harness new (perfect match) from Germany through the Porsche OEM parts system. In fact two came, as they were tangled together, (I returned one back to the dealer). I will get you the part numbers tonight and maybe that will help the dealer locate one. Jim

[Thomas Owen]

Just be careful that you are not working with a 'symptom' and rather the 'problem'. In other words, make sure something connected to the harness did not cause the problem. Hate to see you plug in the new one and have it melt as well...

[Sunroof]

The OEM part number is 91161201730 and it retailed for $133.50, however, according to Porsche, "not one exists on the planet". I am in agreement about a junkyard unit, its risky. I will let you know as this progresses, but the way I see it, the fittings are just fine, its the bundle in the center thats alittle melted together. I will probably opt for splicing, soldering and getting it back together with the original fittings.

Bob

[paulo]

Bob,
I own a '73.5 911T coupe which has been completely stripped of all components including wiring. I probably will not re-use the 31 year old original wiring harnesses. In my research, I asked my Porsche dealer to get a quote on replacing all the wiring in the car with Porsche OEM pieces. They are available from Porsche as a special order. I believe they make up the harness(es) when requested using all new material.
The original 1973 911 spare parts book lists the "cables on the regulator plate (Bosch) in the engine compartment as part number 911.612.004.10 available from Germany for $365.98 (Canadian). That quote is about one year old. Delivery would take three to five weeks.
I don't know the extent of the damage but you may need to replace some of the wiring coming through the tunnel from the front of the car.
You are not alone with this problem; as these cars age there are serious problems with the wiring, fuel and brake systems that will have to be addressed by owners. My advice is not to take the easiest/cheapest solution but to take your time and effect a permanent and safe fix. Electrical problems can sometimes morph into serious fires with bleak results.
Cheers for now!
Paulo

[paulo]

Bob,

Just read your post with part number 911.612.017.30 for wiring harness to engine (alternator). This along with 911.612.050.01 cable set for the ignition coil may be the more specific wiring that needs replacement than the one I quoted (612.004.10). Just to clarify, your Porsche dealer may say that none exist in stock (on the shelf) but I have been assured that any Porsche dealer can order them from the factory in Stuttgart as a special order that must be manufactured, therefore the delivery lead time of three to five weeks. Ask your dealer to run a query on the part number thru PCNA to Porsche Stuttgart. The computer should provide current pricing. I have not actually placed a firm order for 911 wiring from Porsche so cannot actually confirm what my dealer says is possible.

Paulo

[Sunroof]

Paulo.
I greatly appreciate the response. I picked up the harness from the shop and the damage is located more in the center portion of the wiring between the two largest fittings. None of the fittings seem to be damaged. The original fittings are all in good-excellent condition and with that said, splicing in fresh wires (cut, clean and solder), inspecting and cleaning the others and adding additional protection is the most cost effective and best fix.

My repair is in great hands.............unfortunately I cannot gain any extra horsepower out of the fix!!

Regards
Bob
73.5T

[rattlsnak]

Bob, your harness is done.