Wiring harness strategies.

Keep in mind that the engine harness is a separate item from the chassis harness.
And never forget that the 1974 harness is completely different in the chassis and engine harness.
 
There is probably no need to replace all the harness, most of it will be ok, usually it is the connector ends that get damaged or where there may be a little movement in the harness. I have fixed lots of wiring by just replacing the connectors and what ever damaged wire. I DO NOT use heatshrink connectors ( too bulky, not original ) Get the double crimp connector's like the original set up and either the rubber boots that go with the connectors or heat shrink tubing I know some guys like that braided split plastic loom covers but in a BMW ( or any European car ) but I think that it looks hideous Use the proper PVC black tubing that BMW uses . Also make sure that the crimpers that you have will do the proper double crimp Here some pictures of some of my electrical supplies The bunch of those long clear connectors are what BMW uses to have something in the loom that has to come apart These pictures are from a 70 ti that i am restoring for a fellow, this is the wiring connections for the driving lights

Thanks, Rick
 

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jmackro said:
Ha ha. Looking at their website, all their car-specific harnesses are for 'mericun cars. Click on "MAKE" on this site and you'll see what I mean: https://www.painlessperformance.com...mOXy2pNdyHAGR2r75FpeeELmsoM3cR90aAtP0EALw_wcB

I guess the universal harness would be Painless' solution for an e9, though I would think that once you had adapted it, it would have been simpler/cheaper to fabricate a harness from scratch (though I see that user "nosmonkey" reports using the universal harness in post #7, so I should defer to him).
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I agree. I would at least want to try toi maaintain the same wie color codes, since that matches the diagrams...So a gneric harness, however convenient, is just adding a new problem...
 
Having looked under the dash a tiny bit, looks like the lighting circuit wires are the most stressed and melted. Also some melting in the relay connectors by the batteries. I think I'll try to make a flat platform I can lie on and look under the dash. I so hate trying to contort myself trying to figure out what is going on under there .Must be torture if you are tall.
 
sfdon said:
Remove the seat and steer wheel?
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Yes, I will remove the seat eventually. Steering wheel is just trial fitted so it just pulls off. My car is on jack stands , so if I lie on my back flat and looking up that would help. As it is now it is very un ergonomic for my body to have a look up there.
 
Nicad said:
Yes, I will remove the seat eventually. Steering wheel is just trial fitted so it just pulls off. My car is on jack stands , so if I lie on my back flat and looking up that would help. As it is now it is very un ergonomic for my body to have a look up there.
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I have a cut in half matrass for those jobs in my garage. Works wonders, and makes the upside down jobs at least 50% less annoying.
 
stphers said:
Also, for tape, I use Tessa cloth hockey tape We have that in abundance here in Canada

Thanks, Rick
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I am wondering, if we are seeking OEM originality, including using the same somewhat long-term unreliable connection technology, shouldn't we also be using OEM tape for the harness? I mean, HOCKY STICK TAPE? that's not what BMW used!! :D

www.wwiisoldier.com

German Friction Tape, WWII Reproduction - WWII Soldier

German Vorwerk Friction Tape is a WWII era reproduction wax wrapped friction tape.
www.wwiisoldier.com www.wwiisoldier.com
 
Scott, don't take this the wrong way but being from California, have you ever used hockey tape? HA HA It is so close to original, I don't think that you could tell the difference AND you can beat the crap out of it and it stands up to it. It is even hard to cut with razor knife. Think of the beating it takes on a stick on the ice, hmmm Plus, it doesn't cost over 15 bucks US, only about 4 bucks Can. which is what these days about 80 cents US ? ( just kidding about 3 bucks US )

Thanks, Rick
 
stphers said:
Scott, don't take this the wrong way but being from California, have you ever used hockey tape? HA HA It is so close to original, I don't think that you could tell the difference AND you can beat the crap out of it and it stands up to it. It is even hard to cut with razor knife. Think of the beating it takes on a stick on the ice, hmmm Plus, it doesn't cost over 15 bucks US, only about 4 bucks Can. which is what these days about 80 cents US ? ( just kidding about 3 bucks US )

Thanks, Rick
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What's hockey? o_O LOL!
But ooofhz! Zat Canuck hooky tapez. Icht nicht original! :cool:..

Sure, of course it is made to last, and probably does the job better!. I'm just pullin' yer chain mate..

Hey $15 per yard of WWII crap vs modern technology at $0.15 per yard? Why not?

Sometimes these E9 folks get mighty particular about perfection, ya nooo.

S
 
A rewire is definitely not for the faint of heart. A dash out job imo. What I liked with the painless harness is having the wires labelled on the wiring as well as more modern blade fuses. however being a rhd car some pieces for the cluster wiring were a bit shorter than I'd have liked. Horn, hazard and indicators are relayed on the fuse box, lights have a seperate relay box along with cooling fan hidden behind the front left headlight assembly. I ended up also replacing the factory hazard and fog light switches with some more universal ones and headlight switch is off a beetle which is very similar. This is more for future parts availability than anything else.

A very time consuming job, this took the best part of 2 months on and off.
 

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FYI, some other information on isolation tape and comparisions to original here:

Quest for originality; Cable wiring harness tape & PVC connectors?

I've purchased some tape to refresh the wiring harness. However seeing it side by side I see difference. The original is a genuine textile with a warp and weft , the new roll of tape is just fuzzy fibrous. Does anyone have a source for a textile tape that is matching (better?) Preferably in the...
e9coupe.com e9coupe.com

it also has some experiences noted from my side about how i tackled things, with the pro's and con's listed...
 
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