GT mediated Awesomeness

[Jaba]

Good work Tom. I am glad it is you doing it not me. BTW some of those extra relays are probably for the twin rad fan operation.

[saintjamesy89]

It's getting a bit serious to be honest! I didn't think that the instrument cluster wiring would be a part of the whole front/engine bay harness

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You're absolutely correct John, I've drawn diagrams of each relay and exactly where each wire goes, three of the TRS' relays involve operating the twin fans, one controls the a/c compressor and another is connected to the smaller engine connector under the battery tray (the GT doesn't have this connector and the other end was unplugged, i woudl guess its somethingto do with the emissions conntrol system, as there are extra electrical connectors on the TRS' old carb).

I've started splitting the TRS loom this morning, but before cutting anything I will do the same for the GT loom now it's off to make sure i know what needs to stay on each car and what needs to go. The last thing I need is two inoperable cars and a pair of butchered looms!

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I have a few more hours today and tomorrow aswell, then it's back to shifts - so I need to get as much done as possible. If I could finish the electrics, that would be amazing as I'll probably forget what I'm doing if i stop for a week.

[saintjamesy89]

A good day yesterday, I was really getting my head around dividing the looms, we went out for dinner last night so had to stop early to clean up, walk the dogs etc. Unfortunately I had to leave the wiring in a bit of a mid-processing mess!

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After much head scratching, note writing and unfortunately a few wires needing to be cut, I believe the TRS loom is ready to go back in! It's laid out in the pics below with rough locations for each headlight area, battery, fibreboard and instrument cluster - these are obviously where all the main connections are.

This loom came from the TRS and is going back in

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This is the portion of the original TRS loom WITH the section of the GTs loom that needs to go into the TRS. The main bits needing to go from GT to TRS was the rad fan stuff, simple on the GT but much more complex on the TRS stuff with all the twin fans controls.

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[saintjamesy89]

This is the portion of the GTs loom that it will keep, getting there!

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I will hope to have the looms installed, plugged in and hear the cars run today, so fingers crossed.

Edit to show the complete new GT loom, with all a/c extras!

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[panky]

Why do I fancy spaghetti all of a sudden

[saintjamesy89]

A bit if a tricky afternoon, it took ages wrangling the loom back into the car and in the process, some of the crimped wire connections came loose and two even came out of the crimp.

I've not read into/understood the crimp connections, of which there are 5 in the whole loom, but I have a hunch its a switched. 12v power supply to various items.

I also had issues with the coils, the GT and TRS seem to have different wires on the top posts if the coil. As I'm sure many know, two of the coil wires come from the ignition module and two from the fuseboard. Perhaps different coils or ignition modules for the 16 and 19?

TRS with the remaining two wires from the IM in different places!

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GT with the two front wires coming from the ignition module.

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[Jaba]

Can't wait for the next bit when the reconnected and repaired loom starts the motor up instantly.

[saintjamesy89]

Can't wait for the next bit when the reconnected and repaired loom starts the motor up instantly.

Let's hope!

I'm busy elsewhere today and am back to work tomorrow, next opportunity is a few hours Wednesday afternoon and all day Thursday. But progress is good

[saintjamesy89]

Bloody work is getting in the way! I have quite a heavy shift pattern over the next two to three weeks before we're off to France for 10 days - I really want to get this wiring as finished as possible before we go or I'll forget what I am doing.

I popped over to the cars this morning before pre-nigh shift sleep to get my notebook with all the crimp wiring routes, I have bought a few distribution blocks to replace these crimped wires in the hope that no more come loose, I plan to move them to safer locations too, there are two by the bulkhead that can be moved inside the car, one in the middle of the bumper/rad fan section and another just in front of the passenger headlight, the latter two can be moved to behind the passenger headlight for a but more wet/weather etc protection.

What I call a 'crimp'

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The GT has 4 crimped junctions that connect one side of the circuit for quite a few of the lower powered items such as sidelights, indicators, instrument cluster lights etc. I'm still unclear if these provide the earth or switch/12v for certain things, I am not very good at understanding Haynes wiring diagrams, but I don't think I need to understand it all here as long as the original wire still has the same connections and destination - I'm hoping we're good!

One other thing here, one of the horns doesn't work, the fog lights don't work and the new LED headlights don't go full beam on the normal switch (but do in the flasher button!) - so I am thinking there is an earth issue on this circuit, I plan to run a new earth from the inner wing earth point (behind and below battery) to the horns, hopefully this sorts the problem. I will also be replacing the 'crimp' wire that goes to the LHS fog light, the existing wire has partly melted, another potential fix for that circuit.

Where things are right now, pretty much the loom is in and good, apart from the repairs needed for the crimped sections and minor jiggling to allow enough length, I'll have to cut open some of the tape as the LHM reservoir and indicator connectors are now not long enough!

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Thursday is the next day I have for the GT, it should be a night shift recovery day but I do need to get on! Until I hear the car run I am going to be anxious about cocking it all up
I am also about to order some LEDs for the indicators, sidelights and will investigate instrument cluster LEDs, I'm going to look into tidying up the relays aswell.

[Jaba]

The two horns are wired in parallel so that if one fails the other one still works. Trouble is they are are up in the LHF wing and difficult to get to on a Mk2 don't know if yours is different.

[saintjamesy89]

It is the same on the MK1 as far as I can remember, I have been in and looked a year or two ago - I even bought two replacement horns, IIRC I moved a connector around so at least one was working. I do need to revisit them though!

[saintjamesy89]

In other news, yeaterday I finally sorted the drivers front caliper on the C6, I rebuilt the passenger front a few months ago which was by far the worst of the two.

Crusty! No wonder this brake was dragging.

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The bleed nipple was unsurprisingly reluctant, an 8mm spanner was immediatelmy no good and my twist grips were with the GT half an hour away! So I had to be very careful with a pair of vice grips, just about managed it by the look of things! New bleed nipple installed of course.

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New pistons, seals and gaiters - much better.

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The MOT is due in a week or two, apart from a clicking driveshaft (probably related to both front brakes dragging) i hope all will be well with it.

[saintjamesy89]

I have more progress to report! Another half a days work saw the finishing of the engine bay wiring loom, installation of the compressor (i forgot how fiddly that is on a BX!) and getting the car running again - so good stuff.

I ordered some terminal blocks off the jungle website, they are much larger and more substantial than expected! Probably way overspecced for this car tbh, unfortunately only two out of 4 were delivered before I set off this afternoon, so I couldn't repair and move the crimped wires by the bulkhead.
I unfortunately also.found more crimped sections, but these were on thicker/larger wires which seem to have held up better, let's hope they are still good!

So, the two crimped wiring sections around the radiator fan area have been relocated to the base of the LHM tank, repaired and sorted. I tiied up the loom aswell and the connectors are all plugged back in in the entirety of the engine bay.

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Moving on to get it running again, I checked the ignition coil wires, put the inner wing and battery earths back together, installed the battery and checked all the fuseboard connections inside - a twist of the key, and we have a running BX again! Albeit, very birefly. She keeps starting, then stalling shortly afterwards (video to follow). She can be made to.run with throttle, but is msifiring/lumpy.
Not sure what I have done here, the ignition system from the fuseboard is only 3 wires

As she rose up on her stilts, I could get underneath and remount the compressor - fiddly bloody job!
Dirty sump but with new metal spacers, although in this phoro I have them the wrong way around it seems, the larger spacers in fact go on the RHS lugs of this berlingo XUD alloy sump to provide the proper belt alignment with the alternator.

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Curiously there was a small gap between the compressor and rhs sump mounting lugs, I had a few rubber washers handy so one of these slotted in the gap just right - might even help with the vibrations too

Back again on Monday, which will.be my last time before were off to France, I really want to get these electrics sorted before then...

[saintjamesy89]

What the GT is doing, apart from ignition wiring the only thing I have changed is to replace the crusty autochoke coolant hoses, same routing - just new hoses. Perhaps an air lock is causing the choke to stay closed? Therefore causing a too rich splutter and stal

[saintjamesy89]

It also occurred to me that this behaviour is exactly what the TRS was doing with its new carb, that also has had new autochoke coolant lines but I do remember the choke flap being open on that one.
Both dashboards are out of course and so not all fuseboard connections are present, I shan't worry about it until everything is back together I think.