1986 Daihatsu Skywing - Progressive wiring loom failure?

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Sat 3 Sep 2022 14:11
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

Temperature gauge and radiator fan control switch relay earth circuit have been out for a while, though I ran a bypass wire from the temperature switch for the fan relay earth which restored fan control function.

Now the fan relay solenoid live side is out, and I've lost one (out of 3) indicators on the drivers side, and 2/3 on the passenger side. Bulbs and bulb holder contacts seem OK.

Maybe just age/heat/ozone/humidity causing perished insulation and corrosion. I could run some more bypasses, but I should probably open up the wiring loom. Groan!

If I un-tape it, which I don't fancy much, I'm thinking I should put it into that corrugated conduit stuff (if I can find it here) or some split tubing, to maybe make tracing easier in the future, if there is a future.

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Sat 3 Sep 2022 23:24
1986 Daihatsu Skywing - Progressive wiring loom failure? - Andrew-T

Sounds like a scurrilous plot by the CCP on the mainland .... ?

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Sun 4 Sep 2022 01:02
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

Sounds like a scurrilous plot by the CCP on the mainland .... ?

I think getting China to do your wiring (and nuclear reactors!) is more a Yook thang.

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Sun 4 Sep 2022 00:54
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

These "signal injector" thingies any good on cars?

www.youtube.com/watch?v=Y0HjaR0tj7Q

Demo isn't very convincing, and that's with the loom out and on the ground, which one might want to avoid.

I've heard (and may have posted) of a trick exploiting crackles on the car radio when the wire is waggled, but I'd have to fix my car radio.

Catch 22.

Suppose I could get hold of an AM radio somewhere.

Edited by edlithgow on 04/09/2022 at 01:11

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Sun 4 Sep 2022 07:55
1986 Daihatsu Skywing - Progressive wiring loom failure? - paul 1963

Sounds like the end is in sight for the skewing, time to move on to another car ...

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Sun 4 Sep 2022 08:30
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

Sounds like the end is in sight for the skewing, time to move on to another car ...

The end was in sight when I bought it, and remains so, but if I move on it'll likely be back to The Yook, where I probably couldn't run a car.

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Mon 5 Sep 2022 12:26
1986 Daihatsu Skywing - Progressive wiring loom failure? - galileo

Sounds like the end is in sight for the skewing, time to move on to another car ...

The end was in sight when I bought it, and remains so, but if I move on it'll likely be back to The Yook, where I probably couldn't run a car.

I'm sure if you wanted a car to run here you would find helpful advice on this forum in finding one meeting your preferences and budget?

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Tue 6 Sep 2022 01:46
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

Sounds like the end is in sight for the skewing, time to move on to another car ...

The end was in sight when I bought it, and remains so, but if I move on it'll likely be back to The Yook, where I probably couldn't run a car.

I'm sure if you wanted a car to run here you would find helpful advice on this forum in finding one meeting your preferences and budget?

A bridge still to be crossed, but I doubt its doable.

Essentially, I have an old tech (pre-cat) banger. I like old tech (pre-cat) bangers

Old tech (pre-cat) bangers, pretty much by definition, no longer exist.

You can have an old tech (pre-cat) classic (rather rare in Taiwan, essentially restricted to the original Mini, VW Beetle, and Datsun 340, more choice in the UK, pricy both places) or you can have a new tech banger.

A new tech banger has limited appeal and would be difficult to maintain.

I have a small flat in Edinburgh. I used to maintain my old tech (pre-cat) bangers in the street, but it was pretty miserable in winter, unlike Taiwan there was a high risk of getting your tools stolen, granite sets (like square cobblestones, the local road surfacing) are fantastically dangerous to jack a car up on, and increased parking restrictions since I left would complicate things further.

I'm probably too old and creaky for all that hassle now, and it wouldn't be a suitable regime for a non-disposable classic.

So, given all that, and the UK's uniquely unaffordable fuel prices, I think I'd be relying on a bus pass back in Blighty

Edited by edlithgow on 06/09/2022 at 02:11

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Wed 7 Sep 2022 10:45
1986 Daihatsu Skywing - Progressive wiring loom failure? - Bolt

I think I'd be relying on a bus pass back in Blighty

if you suffer arthritis or back trouble you wont be using a bus, I only used one once and never again, but agree with the rest car prices for what you get second hand are extremely overpriced and good cars even harder to find than years ago imo....in fact looking for bil a few weeks ago after a Vauxhall Zafira gave up as either overpriced, all had slight damage poor repair, or not at all, all needed work done that owner couldn`t afford to do.... so keeping his old 2004 car in better condition than all of them

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Wed 7 Sep 2022 13:52
1986 Daihatsu Skywing - Progressive wiring loom failure? - galileo

Essentially, I have an old tech (pre-cat) banger. I like old tech (pre-cat) bangers

Old tech (pre-cat) bangers, pretty much by definition, no longer exist.

You can have an old tech (pre-cat) classic

There is a programme we watch called "Bangers and Cash", which follows Matthewsons car museum and auction business in Thornton-le-dale.

They regularly sell old-tech 1950s/60s cars for as little as £2000 - 3000, those over 40 years old are MOT- exempt and road tax is free!

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Wed 7 Sep 2022 14:09
1986 Daihatsu Skywing - Progressive wiring loom failure? - Andrew-T

There is a programme we watch called "Bangers and Cash", which follows Matthewsons car museum and auction business in Thornton-le-dale. They regularly sell old-tech 1950s/60s cars for as little as £2000 - 3000, those over 40 years old are MOT- exempt and road tax is free!

I watched them sell the remains of a 1960s Mini a few months back. I think only about three-quarters of the car was left, but it still fetched silly money.

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Thu 8 Sep 2022 02:44
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

There is a programme we watch called "Bangers and Cash", which follows Matthewsons car museum and auction business in Thornton-le-dale. They regularly sell old-tech 1950s/60s cars for as little as £2000 - 3000, those over 40 years old are MOT- exempt and road tax is free!

I watched them sell the remains of a 1960s Mini a few months back. I think only about three-quarters of the car was left, but it still fetched silly money.

I once paid 1800 quid for a vehicle, but that was a Renault Dodge ex-BT workshop truck camper about the same size as my flat. Everything else has been under 500.

Some adjusting to current reality might be required.

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Sun 4 Sep 2022 09:20
1986 Daihatsu Skywing - Progressive wiring loom failure? - Bolt

Temperature gauge and radiator fan control switch relay earth circuit have been out for a while, though I ran a bypass wire from the temperature switch for the fan relay earth which restored fan control function.

Now the fan relay solenoid live side is out, and I've lost one (out of 3) indicators on the drivers side, and 2/3 on the passenger side. Bulbs and bulb holder contacts seem OK.

Maybe just age/heat/ozone/humidity causing perished insulation and corrosion. I could run some more bypasses, but I should probably open up the wiring loom. Groan!

If I un-tape it, which I don't fancy much, I'm thinking I should put it into that corrugated conduit stuff (if I can find it here) or some split tubing, to maybe make tracing easier in the future, if there is a future.

I think i would be inclined to check the wiring to connection joints rather than cable itself as they tend to corrode inside the crimped joint, most old cars i have looked at for wiring faults were caused by where cable copper had corroded inside the crimps or at the connection on a block connector

Only on exposed wiring did i find cables insulation cracked mosly on flexing cables and causing either a short or very high resistance to prevent full power being given to supplied component. I know age makes insulation brittle over time anyway but dont usualy break untill you move them then the problems start ie they have to be replaced

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Tue 6 Sep 2022 02:05
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

Temperature gauge and radiator fan control switch relay earth circuit have been out for a while, though I ran a bypass wire from the temperature switch for the fan relay earth which restored fan control function.

Now the fan relay solenoid live side is out, and I've lost one (out of 3) indicators on the drivers side, and 2/3 on the passenger side. Bulbs and bulb holder contacts seem OK.

Maybe just age/heat/ozone/humidity causing perished insulation and corrosion. I could run some more bypasses, but I should probably open up the wiring loom. Groan!

If I un-tape it, which I don't fancy much, I'm thinking I should put it into that corrugated conduit stuff (if I can find it here) or some split tubing, to maybe make tracing easier in the future, if there is a future.

I think i would be inclined to check the wiring to connection joints rather than cable itself as they tend to corrode inside the crimped joint, most old cars i have looked at for wiring faults were caused by where cable copper had corroded inside the crimps or at the connection on a block connector

Only on exposed wiring did i find cables insulation cracked mosly on flexing cables and causing either a short or very high resistance to prevent full power being given to supplied component. I know age makes insulation brittle over time anyway but dont usualy break untill you move them then the problems start ie they have to be replaced

Thanks

Taking the front off to get at the loom, but having a lot of trouble with some recessed shouldered nuts. (outside portion round, inner flush portion with a very shallow hex) holding the bumper.

I dunno what special function this shape has (IIRC nyloc's are often like that) but it doesn't include engaging with any of my spanners. 10mm seems too small, 11mm seems too big.

If I ever get them off I wont be putting them back on again.

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Tue 6 Sep 2022 10:16
1986 Daihatsu Skywing - Progressive wiring loom failure? - Andrew-T

<< If I ever get them off I wont be putting them back on again. >>

You will gradually wind up with a go-kart ....

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Tue 6 Sep 2022 20:18
1986 Daihatsu Skywing - Progressive wiring loom failure? - Bolt

I dunno what special function this shape has (IIRC nyloc's are often like that)

some have opposing slits that clamp to the screw or thread, others were tapered so they locked to the thread without damaging the thread but are tighter to remove if rusty/dirty, ps not 3/8th nut are they?

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Fri 9 Sep 2022 00:48
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

You can apparently get non-metric sockets here which MIGHT give a better fit, though I wouldn't be very confident.

There isn’t much hex there, its corroded, its in a recessed web,bracket with flanged edges which isn’t very substantial, and the fastening was originally mostly perfectly round when it went in before it corroded.

IOW they were specifically designed to be a PITA to remove.

Hammering a socket on wont work.

I broke my nice spring-loaded centre punch trying to drive one around, and I got my nice bought-in-Japan Lobster brand adjustable (or at least nice for an adjustable) immovably wedged on another open end I was using as a tommy bar.

Thats it. These’ll probably need cut off but there are a few of them, access is tricky, and I probably havn't found all the fastners. It isn’t worth it right now. Some other time, maybe.

I unplugged all the lights, labelled the wires, put strings on them to hopefully help pulling them back, and worked them out backwards, skinning my hands a bit more. A local mechanic came up to "practice his English on me" over my shoulder, which I found unreasonably irritating.

I removed the battery which was in the way.

No problem thinks I, I'll just hook it up with jump leads for a quick test before the light finally goes.

Then I made a very stupid schoolboy/silly old f*** mistake.

Edited by edlithgow on 09/09/2022 at 00:57

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Fri 9 Sep 2022 20:48
1986 Daihatsu Skywing - Progressive wiring loom failure? - Bolt

There isn’t much hex there, its corroded, its in a recessed web,bracket with flanged edges which isn’t very substantial,

Not sure about this, but didn`t some countries use threaded rivets where you tightened up a bolt into what looked like a nut and when tight compressed the nut, if so they can`t be removed they have to be chiselled out, some used them in places where a rivet could shake loose where a threaded rivet once in place couldn`t be removed or fall out?

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Mon 12 Sep 2022 03:40
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

I've got about a 4 amp key-on-engine-off drain, which seems a lot, and suggests short(s)

Removing the fuses one at a time, fuse 7 ("engine") reduced the drain to about 3.5 amps, possibly due to eliminating a "normal" ignition circuit drain.

Removing fuse 7 (15 amp fuse labelled wiper/indicator) reduced the drain to about one amp. This fuse blew earlier, making this circuit prime suspect.

I repeated this procedure next day after removing my non-generating alternator, which I thought might be a leakage path.

Removing fuse 7 now made no difference. I interpret this as suggesting the short now bypasses that fuse, either via another circuit or shorting to earth before it.

IOW its spread in the loom. Melt-down

I have continuity to earth from all the indicator + terminals I have ready access to (sidelight and bumper. Havn't checked the wing lights) with the switch / hazards off. I initially assumed this means they are shorted, but I've never checked it before

If a thermal flasher unit was "on" initially, I suppose it might be normal

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Wed 14 Sep 2022 05:31
1986 Daihatsu Skywing - Progressive wiring loom failure? - edlithgow

I took all the 10 panel fuses out, and (with battery and alternator out and key on) checked continuity between the half-circuits

Excluding earths (some of which could of course have been shorts-to-earth) I found no dead (buzzer-triggering) shorts between circuits, which was nice

BUT there were quite a lot of worryingly low values of resistance, about 7 in the 3-400 ohm range and 7 around 100 ohms for the "upper" half of the panel (10X10 matrix minus 4 earths and selfs) and 4 around 700 ohms for the lower half of the panel. (10X10 minus 4 earths and selfs)

I assume this is not normal and that these are partial shorts, say between melted wires, or between tracks behind the instrument panel, but I havn,t done this before so am not certain.

Does this interpretation seem reasonable?

Visual inspection has so far revealed no obvious damage, but I havn't done much dismantling yet.

Edited by edlithgow on 14/09/2022 at 05:39

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