Disco 1 Fire on top of the gearbox

Brand new, first time Landy owner here. Bought a '93 Disco 1 a week ago, been running ok despite being somewhat beat up (drove it home some 100 miles without issue etc.). Yesterday, however, I ran into a big problem.

I was driving home and noticed I was trailing some smoke and caught a whiff of a weird smell. As I stop at traffic lights, I noticed the clutch was suddenly completely limp and went straight to the floor without much effort. Next thing is smoke billowing from under the car. The engine shut down at this point as well and I lost electrics, too. I tried to apply the handbrake, but there was no resistance. I got out and looking under the car, noticed actual flames on top of the gearbox. I had an extinguisher on board and managed to put the flames out easily.

I had a friend with me and we pushed the car to the side of the road, as it would not start even though the electrics returned after a while. The handbrake lever is completely loose, i.e. the cable has no resistance, and yet the car could be pushed, so it seems the brake is not doing anything. I took off the handbrake gaiter, and it seems the cable has some melted plastic on it and has fused to the rubber plug it runs through. In short, the handbrake cable is not moving in any direction.

Later on in the evening I got a tow back home from a friend, and we actually got the Landy started in my yard with a battery booster, and it could be driven as well, so mostly everything seems ok in that regard. The handbrake is still non-functional.

Any ideas what could have caused the fire and what to diagnose next? I'm not too experienced with cars in general, but I have an idea what it could be. Still, I'd rather hear from someone with more experience first so as not to lead anyone astray with my own, possibly erroneous, diagnosis.

Handbrake cable has become live from touching a live cable or a bad earth from the battery has used the cable as an earth which it can't handle so has melted.
If the clutch hose melted in the fire that fluid would feed any fire and would give your clutch symptoms.

Welcome

Now the first thing is to get underneath and have a good look underneath, and try to see if fluids oil/ clutch fluid has been leaking onto the exhaust.
You may also have a large earth connection gearbox to chassis and the plastic cover near exhaust can catch fire.

Sounds like a lucky escape.

J

usual cause for melting hand brake cable is poor earths for engine/transmission to chassis and battery, but to start a fire when your not cranking the engine over or using much electrical current might suggest a live short

Welcome aboard

Your earth straps have almost certainly failed ..... thus the handbrake cable has become the only earth return - and melted - it's a known issue on D1's

I suppose you should be grateful that it didn't do it whilst you needed the handbrake for any reason, like being parked on a hill .... with a heavy trailer on ......

There are two earth straps on a D1 - plus the HB cable ( ) ..... IF this was your problem - I'd suggest you fit 3 new ones ( and a HB cable ) ..... adds some redundancy into the system ...

You can guess how I know this

Wow, thank you all for these responses
Makes it so much easier for me to figure out what happened. I was pretty shaken and almost certain something had gone wrong in a big way in the powertrain or something as it all happened, but it seems I'll get away with getting a new HB cable and checking the wiring. The previous owner had done some electrical work on the car, so this seems like the most obvious reason things went south.
I'll let you know how it goes later. Quite a start to owning a Landy

Very unfortunate but lessons can be learned nonetheless. My question here is this - why would the clutch go completely limp and straight down to the floor and then seemingly come back to normal that same evening ? I mean, what's the connection between the clutch system and what happened here ?

NPG said:

Very unfortunate but lessons can be learned nonetheless. My question here is this - why would the clutch go completely limp and straight down to the floor and then seemingly come back to normal that same evening ? I mean, what's the connection between the clutch system and what happened here ?

Click to expand...

I wondered that too but he says it could be driven ,which you can do without clutch release so I just assumed that.

Arttu Korppivuori said:

The previous owner had done some electrical work on the car, so this seems like the most obvious reason things went south.

Click to expand...

Shame he didn't check the Earth straps then ...... .......

They're part of my maintenance regime now ( ) - we've both got D1's - and they've both got 3 earth straps - and nice shiny connections to their respective areas .... all covered in vaseline ......

Arttu Korppivuori said:

Quite a start to owning a Landy

Click to expand...

Baptism of fire ........................ ( sorry, couldn't resist )

NPG said:

Very unfortunate but lessons can be learned nonetheless. My question here is this - why would the clutch go completely limp and straight down to the floor and then seemingly come back to normal that same evening ? I mean, what's the connection between the clutch system and what happened here ?

Click to expand...

I'm still pretty puzzled by the clutch issue as well, haven't had time yet to check anything. However, could possible air in the hydraulic fluid react to the heat of the fire and result in something like this? Once I got the Disco back home, the clutch seemed to work completely normally again, I could put the car in gear without issue etc.

Maybe, just maybe, the clutch pipe got hot and too flexible, when you applied pressure it simply expanded it and the fluid did not have enough pressure to operate the clutch. Once it cooled, it would harden again and then operate like normal? give it a real good look to see if there is evidence that happened. I expect you'll change it anyway, if you haven't already.
Clutch going while driving has happened to me a few times and it is a pain changing gear without it. Never even tried it on a LR but i expect it is more difficult than in a car.

Arttu Korppivuori said:

I'm still pretty puzzled by the clutch issue as well, haven't had time yet to check anything. However, could possible air in the hydraulic fluid react to the heat of the fire and result in something like this? Once I got the Disco back home, the clutch seemed to work completely normally again, I could put the car in gear without issue etc.

Click to expand...

I'd check the level of the clutch (brake) fluid and top it up if it's low. After that, keep checking it at regular intervals as I suspect that the heat may have caused the rubber inside the slave cylinder to become soft and allow fluid to go past. Once it cooled down, it started sealing again but may not have regained its original strength.

Finally had time to do a bit of digging and crawling last night. Under the bonnet things seem more or less ok. To begin with, I'm not seeing any leaks anywhere, and the fluid in the clutch and brake reservoirs looks clean and the level is correct.

The clutch pipe has obviously been quite hot, as the vacuum hose to the brake booster has melted a bit on two spots where the two have been in contact. The booster has been leaking since I got the Landy so that's up for a replacement anyway, might as well swap out the hose as well when the time comes. A plastic hose near the clutch slave cylinder has also melted a bit.

Checked the battery with a multimeter, the voltage was 12.13, so obviously a bit low, but that was to be expected. I also see a constant draw of 0.64 amps. The chassis earth points clearly haven't been touched in ages, so there's that. Also, I'm not finding an earth to the bodywork anywhere in the engine bay, should there be one? All I found were battery negative to chassis and starter to chassis.

Under the car, the handbrake cable plastic coating has burned / melted off, and there is a pair of exposed wires on top of the transfer case. Not sure if these were what shorted out originally or if they've burned as a result of the HB cable heating up. I've tried figuring out what these wires are for, but I have no idea.

EDIT: Ok, tried inserting links to images but they're not showing. I can't forum, I guess. Images here on imgur

Wires on gearbox are for reverse light switch.
Wires on transfer box are for diff lock warning switch.
This is on defender though but disco should be the same.
Handbrake 'on' warning switch will be around there somewhere too but I've never owned a disco and my 110 has never had one so I'm not sure where that would be in relation to the fire.
I've also no idea where body earth's would be on a disco but I bet @Disco1BFG knows.

Flossie said:

Wires on gearbox are for reverse light switch.
Wires on transfer box are for diff lock warning switch.
This is on defender though but disco should be the same.
Handbrake 'on' warning switch will be around there somewhere too but I've never owned a disco and my 110 has never had one so I'm not sure where that would be in relation to the fire.

Click to expand...

Makes perfect sense, I'll don my dunce cap
I don't remember the diff lock warning ever working, to be honest. And the handbrake on switch is next to the handbrake handle in the cabin, that one I found and figured out earlier.

Flossie said:

Wires on gearbox are for reverse light switch.
Wires on transfer box are for diff lock warning switch.
This is on defender though but disco should be the same.
Handbrake 'on' warning switch will be around there somewhere too but I've never owned a disco and my 110 has never had one so I'm not sure where that would be in relation to the fire.
I've also no idea where body earth's would be on a disco but I bet @Disco1BFG knows.

Click to expand...

Yep - plus on a D1, there's the wiring to the speedo transducer instead of a cable..... ( edited to add - yours may be old enough to still have a cable drive for the speedo - maybe ....)

The body earth point on a RHD D1 is behind the battery and in front of the main fuse box where the inner wing is at 45 degrees - the battery -ve cable is bolted to the inner wing ....

@Arttu Korppivuori if a picture would help, let me know and I can take one for you later......

Also - if your earth straps are all like the one pictured - it might be better to replace them with new ones - I got mine from the local lorry repair place - so they're heavy duty braided ones .....

Disco1BFG said:

Yep - plus on a D1, there's the wiring to the speedo transducer instead of a cable..... ( edited to add - yours may be old enough to still have a cable drive for the speedo - maybe ....)

The body earth point on a RHD D1 is behind the battery and in front of the main fuse box where the inner wing is at 45 degrees - the battery -ve cable is bolted to the inner wing ....

@Arttu Korppivuori if a picture would help, let me know and I can take one for you later......

Also - if your earth straps are all like the one pictured - it might be better to replace them with new ones - I got mine from the local lorry repair place - so they're heavy duty braided ones .....

Click to expand...

Mine's a LHD, but I'll have a look at the wing on the battery side. The imgur link above should open to a gallery of pics I took last night, shows the the two earths I found and the melting damage etc.

The body earth connection is behind the battery as shown for my disco. 100mm or so from the battery terminal.

Arttu Korppivuori said:

Mine's a LHD, but I'll have a look at the wing on the battery side. The imgur link above should open to a gallery of pics I took last night, shows the the two earths I found and the melting damage etc.

Click to expand...

Thanks - just looked at them. The brake servo hose looks like it just worn over 25+ years from the picture ....

The two spade connectors will almost certainly be the diff lock warning light switch wiring - I have a 200 TB in my "spares" pile - I'll have a nosy later...

The HB cable is absolutely kaput - but you knew that - You might struggle to get a new clutch hose IIRC - but it should be possible to have a hydraulics place make one up .....

I notice that your front prop looks the wrong way round - the sliding joint should be at the TB end IIRC - certainly is on our 300's