63 amp cable - short to earth - Oops ! - AA recovery

[tweetyduck]

So my new 100amp alternator is connected to the starter by the standard ~63 amp cable. Not doubled it up yet....

So the wire has been rubbing on the back of the engine block....why does it take that route? Finally it rubbed through on the way back from North Yorkshire around Thirsk....So its got 100amp going into it from the Alternator end and the entire battery from the other. Needless to say its got VERY hot and burnt all its insulation off completely, end to end. In the process it took out the thin wire to the alternator,,,,battery light came on,,,the oil temp wire,,,oil light came on,,,the thermostat wire,,,needle went to red,,,,I poo in my pants and pull over and switch off the engine. Look under the bonnet to find no end of melted plastic. The fuel cut off wire is also trashed but still has a copper path. The pipe from the top of the injector is also slightly melted as is the red white one at the back with that large plug. The pipe i think is a vacuum pipe?? and the red white is unknown (poss a cable to starter relay?)

Miniture swiss army knife in hand (you know the key ring one) i trim all the wires out and remove them all back to the good part. Call AA.

AA turn up and refuse to do anything and insist on taking me back home. All i need is a piece of cable for the alternator to get it back running and the fuel cut off wire sorting. About 30mins work. They said "no". The vacuuum pipe needed a bit of tape to cover the hole and the red white could also be taped up.

So towed all the way back home. Not happy.....

Got up at 8am this morning and 1:30 later all wires temporarily relaced and new ones crimped in replacing the melted bits. Trip to Motosave and got some new ~60 watt cable and connectors,,,trip to farm shop to get some 100amp for the alternator and some new crimps. Another job for the list.

If western reads this, please i need the part number for the vacuum pipe?? and that red white cable with the big connector. To everyone i need to know how best to replace the melted bits. Should i just use automotive crimps? or something better?

If i can fix this on my drive with limited knowledge and parts....how come the AA wouldn't. They have that nice box on the form that says "he told me to do it, its not our fault". They cost themselves a 90 mile recovery......idiots......

[crwoody]

" ...They cost themselves a 90 mile recovery......idiots....."

Free ride home, must have saved you 3 or 4 gallons of juice - don't knock it

[tweetyduck]

it crossed my mind.....I get 9 recoveries but my parts cover has another 7 days till it starts. Doh !

[steve b]

In the field fix = gas soldering iron+solder+heatshrink+new wire...are these items in your on-board list? , at home fix , I 'd get a new engine/gearbox loom and make sure its clipped up properly

..you are getting some cool breakdowns and things to deal witth Neil, its gonna help you lots when you do put the key in the ignition for the main event

cheers

Steveb

[tweetyduck]

Thanks steve but i don't really want to replce the loom. Do you think twist and solder could substitute permanent? Need to go to Vehicle Wiring Products me thinks to get some proper stuff for long term,,,,is my telecoms twist and solder good enough for auto long term.

I'm really getting to know the 110. I already knew what all the cables that melted were for (amazed me that i did) apart from the red white (which i guessed) and the vacuum pipe which goes to the injector (which is a technical monster)....i didn't do bad. If i'd had my tool chest in the back I would have been back moving in under an hour. Even if i couldn't fix it properly i would have bypassed the fuel stop and bumped it although no electrics would have meant hand signals all the way home...hehe

not sure i've ever bumped a diesel......or fixed one (yet) in the field for that matter

However i know i could have fixed this with little more than a swiss army knife,,,if only i'd got some cable.

[western]

I would go for a new engine loom after a fairly big meltdown like that, then you can be fully confident it'll hold up for a long time,

a 300tdi engine loom isn't mega expensive, a 200tdi engine loom from autosparks is around £34, can't see a 300tdi engine loom though.

[JeffR]

Had a similar problem a few years ago whilst on a short break in the Lakes. I had just fitted a set of shiney headers to a V8, but had not lagged them. Heat from header melted all the starter wiring resulting in a starter that would not stop. Now in a normal vehicle, one would merely disconect the F**kin battery - but I had none standard seats..... To the swines in the Ambleside one way system who refused to stop so we could put out the fire I wish you all a great deal of ill will (that's the nice way of putting it).

To cut a long story short we had a bit of a meltdown ended up attempting a re-wire of the engine/starter loom on a campsite with very basic tools (asked wife "Where's the tool box?" "You put it in" , "No you put it in" - bloody tool box was still in Devon landrover was in Ambleside. Still ended up with a nice new socket set, £200 taxi bill and "temporary wiring" that lasted 4 years. Always carry an assortment of different ampage wiring and connectors now. And have a battery cut out switch. Still got the none standard seats though.

Mind you the kids thought it was just bloody fantastic going up over the Struggle on the back of a recovery truck

[nickwilliams]

I spent Saturday morning making a new loom for my 300tdi engine. Very straightforward. You will need:

- about a metre of 6mm sq cable, brown with red stripe (heater plugs cable - goes from bulkhead loom to glow plug: note that the wire between the glow plugs themselves is a different colour)

- about 1.5 metres of 4 mm sq cable, white with red stripe (engine crank cable - goes from bulkhead loom to starter solenoid)

- about 2 m of 25 mm sq cable, brown (alternator main terminal to starter battery terminal) (10mm sq is adequate for a normal alternator, but I'd go for 16 or 25 mm on 100A one).

- about 1.5 m of 1 mm sq cable. white with black stripe (stop solenoid - from bulkhead to injector pump) (NB this colour combination is also used for the rear window heater!)

- about 2m of 1 mm sq cable, brown with yellow stripe (alternator exciter/ignition light - from bulkhead to alternator)

- about 2m of 1 mm sq cable, white with brown stripe (oil pressure warning light - from bulkhead to oil pressure switch)

- about 2m of 1 mm sq (whatever you want - it's not standard, I used black/brown which is the recommended colour in BS AU 7) - (rev counter, if fitted - goes from bulkhead connector to 'W' terminal on alternator)

- about 1.5m of 1mm sq cable, green with blue - engine temperature sender - from bulkhead to temperature sender below thermostat housing)

- about 1.5m of 1mm sq (whatever you want - it's not standard, I used blue/green) - (a/c compressor clutch, if fitted)

- about 1.5m of 15 or 20 mm ID split trunking to protect the wires where they run along the side of the block - needs to have adequate temperature rating.

(All wire lengths are approximate - best go and measure up if you have to pay for your wire!)

- about 300mm of polyolefin self adhesive heatshink sleeving to protect the ends of the trunking (you could use PVC insulating tape, which is what Rists use when the make the loom for LandRover, but I HATE the stuff).

- 8mm ring tag for the starter solenoid end of the brown wire, 6mm ring tag for the other end

- 5mm ring tag for the alternator end of the ignition light wire

- 4mm ring tag for the alternator end of the tacho cable

- 4mm ring tag for the heater plugs end of the glow plugs wire

- 2 x 1/4 in push-on connector (female) for oil pressure switch and stop solenoid

- Matching connector for the a/c compressor (if fitted)

- Bullet connectors for the bulkhead ends (assuming your 300tdi is a conversion - otherwise if it's got 300 tdi wiring you will either have to pay for a loom with the correct connector on, or you will have to chop the 300tdi multiplug off and replace it with bullet/splice connectors).

I can provide instructions for assembly as well, but it's all pretty obvious for anyone who knows which end of a pair of crimping pliers to use. And without wishing to seem elitist, if you don't know how to use a set a crimping pliers then this probably isn't a job for you - bodging this harness has a reasonably high chance of setting the vehicle on fire.

The main thing is to preserve the original 'C' shape of the loom. This means that the heavy duty cable from the alternator to the starter seems to go the long way round but it avoids having to run it past the hot parts of the turbo/exhaust.

Nick.

PS, the remainder of Saturday, and most of Saturday morning, was spent trying to troubleshoot why the panel lights and the engine crank no longer worked correctly, but that's another story, and, it turned out, was nothing to do with the engine loom...

[tweetyduck]

The question is can you run the alternaltor to starter run the short way? Keeping it way from the very hot bits of course...Surely this must be semi normal practice for the split charge, winch, bigger alternator types? Its a lot shorter run so must be better for volts drop.

[FridgeFreezer]

If a new engine loom is ~£50 or so I'd just buy that and then buy some nice thick cable to go from alt to starter, re-doing a loom DIY from scratch is possible but if it's standard it's hardly worth the effort for £50 (even for £100 I'd say it was a marginal waste of time unless you're really bored). By the sound of it the damage is extensive enough that you really want to be replacing the whole lot anyway - there could be all manner of singed stuff hiding where you can't see it.

Twist and solder can be good or bad, as can crimping. Both, if done properly, will be fine.

[Francois]

Im busy with similar problems..... Bad connection on the starter finally caused my glow plug relay to melt. 25 year old wiring isnt looking to good now...

[tweetyduck]

If a new engine loom is ~£50 or so I'd just buy that and then buy some nice thick cable to go from alt to starter, re-doing a loom DIY from scratch is possible but if it's standard it's hardly worth the effort for £50 (even for £100 I'd say it was a marginal waste of time unless you're really bored). By the sound of it the damage is extensive enough that you really want to be replacing the whole lot anyway - there could be all manner of singed stuff hiding where you can't see it.

Twist and solder can be good or bad, as can crimping. Both, if done properly, will be fine.

to be honest it wasn't that bad. the melted bits were limited to the section under the injectors all down the left side of the engine. So no damage really anywhere else. I've tinned the end of new cables today and crimped them in with heat shrink over the butt crimps.

The fuel cut off has a new male spade

The oil pressure has a new male spade.

The thermostat connector is the old one so that has two crimps in the copper path.

The Alternator sense has an new ring crimp.

I've ordered a new vacumm pipe for the injector

The Starter cable is a little more difficult as the connector is a bit weired. Its C449/C203 off the Rave CD. the other end is a spade so no problem.

In all about 4 inches of the loom was damaged and not where its all in a bunch so i think its all going to be fine. I've spira wrapped the parts again and am ordering some more conduit the same as the origional.

Do you think going direct from the Alternator to the starter with 25mm and taking the short route will be OK ???

[PaulMc]

The Starter cable is a little more difficult as the connector is a bit weired. Its C449/C203 off the Rave CD

According to RAVE, that male/female connector goes between the Starter Relay and the Engine Immobilisation ECU.

Polevolt sell a 2-way and 4-way version of that connector - Circularseal Connectors

Which uses .250" (6.3mm) tangless terminals (not standard Lucar type)

These are available separately, from Polevolt, on that page.

If C449/C203 uses the larger .305" (7.8mm) tangless terminals, you can get replacement terminals here -

CN(A) 250-312 Series (Tang-Less)

.

He calls them .312", but they are the correct size - I've ordered them from him before, to use with the same type of connector as C449/C203, and others.

.

[tweetyduck]

Thats the one.. Thanks a million.

I have no Immobilisation so the damage cable just goes from the starter female spade to the relay via the intermediate plug.

[UdderlyOffroad]

All wire lengths are approximate - best go and measure up if you have to pay for your wire!)

Apologies for the slight thread hijack but: Am about to attempt something similar, in that I'm going to redo the loom on my 200 TDi before it gets installed into my 110, as it's not looking too clever. Unfortunately I do have to pay for my wire, does anyone know of a good-value source of cable?

Polevault as mentioned above and Vehicle Wiring Products both seem quite spendy...I appreciate that copper ain't cheap these days but still.

[nickwilliams]

Autosparks are cheaper than VWP per metre, but they are more expensive on delivery.

I have purchased wire from both VWP and Autosparks in the last month. It's worth noting that the VWP lengths came carefully coiled in the separate colours, whereas the Autosparks delivery was all in one big coil which then took me about an hour to separate.

I may be able to help with sourcing enough for an engine loom out of the leftovers I have got. PM me if interested.

Nick.

[UdderlyOffroad]

Thanks Nick, Will PM you.

Am going to make a custom loom with several deviations from the standard one (on board air from a/c compressor, oil pressure sender wiring, boost at the inlet manifold etc.), hence why I don't just put my hand in pocket and buy an Autosparks jobbie.

Might even take pictures/upload a schematic/BOM should anyone think it's of use?

Back O/T, Neil how's yours looking?

[Jim1]

Try car builder solutions prices seem ok but add vat & delivery

[tweetyduck]

Well to update this.

All is done and replaced. I used butt connectors to join the wires and soldered also them for good measure, covered in heat shrink, then sections of new conduit. The ends all had new crimps.

The alternator wire went up to 16mm and again new crimps and glued heatshrink. Covered in heat resistant fibre glass and then routed the short way to the starter and cable tied out the way of anything super hot.

The cable i was having trouble getting was replaced. Used the origional housing but new crimps and again covered in some new PVC sleeve.

Jobs done. Should be good for another 200K. I hope.

Next job is the split charge.....Friday with any luck,,,, and then its neary done.