More head scratching going on with my Land Rover Defender 90, 1986 200TDi (Discovery engine). So I completed some work in the dash, getting the instrument illuminators to work correctly on the proper switch rather than being hardwired to the ignition and fitted some nice LEDs. I also had a go with the fog light as this had been rewired with a dedicated cable all the way to the back - bypassing the fuse box.

Put everything back. Left it a night and went to start. Nothing. Recharged the battery and I got it to start. Took it for a spin and noticed the Temp gauge climbing right up to red on a short 1 mile journey. Slightly panicky, stopped and turned off the ignition. Went to start again and nothing.

After I got recovered home, I switched off and was immediately able to start again, twice. Left it a 10-15mins and tried to start - nothing again.

Each time I try to start there is a clicking down under the fuses. Is there a starter relay there? Some people on other threads say not. I’m getting no voltage engine bay side on the white and red cable.

Perhaps I’ve disturbed some wiring? And what’s going on with the temp gauge to make it climb so quickly?

Any ideas?

Thanks all.

Ignition switch maybe and dash instrument earth. Obviously it's something you have touched so check your work.
Hard to know what previous owners have done during an engine conversion.

Thanks Anaconda. I should add that there was a brief short at one point when i was doing the work (at a time I had the battery connected) between the fog light live feed and another connector and some clicking came from the relay area below the fuses. Could I have upset something there?

Sounds to me like you have a short in the system some where that is draining the battery. Someone bypassed the main loom to the fog for a reason.
An 86 could well have a relay for the starter under the fuses, my 1990 did.
But now has a direct feed from ignition to starter [the little wire] Some issue I found to be in the loom from ignition to relay resulting in irregular start. However I was not going to dig into the loom looking for it.

Have you got a good earth connection to the battery?
And another good connection from the engine to the chassis? If this one is bad the electrikity will try and complete the circuit any other way it can, resulting in odd things happening.

tottot said:

Have you got a good earth connection to the battery?
And another good connection from the engine to the chassis? If this one is bad the electrikity will try and complete the circuit any other way it can, resulting in odd things happening.

Click to expand...

Thanks. Yes, I think the earths are good. It's had a recent professional rebuild onto a new chassis. It was starting fine before I got my mits on the instrument panel. But I'll check through that.....

tottot said:

Sounds to me like you have a short in the system some where that is draining the battery. Someone bypassed the main loom to the fog for a reason.
An 86 could well have a relay for the starter under the fuses, my 1990 did.
But now has a direct feed from ignition to starter [the little wire] Some issue I found to be in the loom from ignition to relay resulting in irregular start. However I was not going to dig into the loom looking for it.

Click to expand...

Thanks. Yes, I did suspect a drain. I hooked up a multimeter between the neg terminal on the battery and the neg battery cable and read no amps. Is there any other test I can do for a drain? I did end up returning the fog light wiring to the way the PO had done it in the end. But I need to look at the other change I made with the instrument lights. I might end up going down that route with the solenoid wire - I recently had to do it on my mini-digger as something in the ignition wiring was causing the starter to continue to turn over after ignition - but that's another story....

To have. a proper look at the loom I probably really need to get more of the dash off. Is it easy to remove the lower part of the dash? Where do you start? Sorry, probably a basic question but I'm a newbie!

The lower dash is just about the only area I have not been into. I could do with re sealing the cabin air flap in there.
As for looking at the loom itself you may well find there is nothing to see unless there has been a big melt down. I have found that it is the case that when melt down happens it is often at the terminal ends were damage is most obvious.

I have done it and involves time and a birds nest mess of wires which will most likely involve manufacturing more problems.
Your symptoms, except temp gauge, was the ignition switch when we had the problem. They are cheap but you need to buy the correct one. Was your battery flat or did you just assume it was flat.

Anaconda said:

I have done it and involves time and a birds nest mess of wires which will most likely involve manufacturing more problems.
Your symptoms, except temp gauge, was the ignition switch when we had the problem. They are cheap but you need to buy the correct one. Was your battery flat or did you just assume it was flat.

Click to expand...

I take your point about the birds nest. I assumed the battery was flat. It was reading 12.2v which I assumed was low. After recharge, the landy started up fine. But then wouldn't restart after a 1 mile journey - battery still should have been strong. So far I do know that, when it won't start, I getting 0v engine bay side on the white/red wire but there is always clicking in the fuse/relay area indicating that there must be current somewhere?!. I'll check what voltage I'm getting nearer the ignition switch. If I can just get to the back of the fuse box / relays AND the back of the ignition switch (and test), I'll have to assume that the white/red wire is intact along the loom. I'm assuming there will be a live cable (brown) connected to the ignition as well.

12.2v is a good voltage, may be an issue with the relay, swap with one of the others to test.
When I was having start on the key intermittent issues I had a stand by rig of a wire from a known 12v feed with a switch in it and a double spade to connect up at the starter, It was under the bonnet so had to be careful when using it [out of gear] Saved the day a number of times.