Melty wires to Ammeter
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Melty wires to Ammeter
Hi all,
There is always a reason someone sells a car or stops using it. So, I have probably just found out why the '65 New Yorker I have just obtained seemed a bit too good to be true. Was investigating wiring around steering column with a view to converting my reversing lamps to yellow indicators and found burnt insulation. I reckon smoke came out of the dashboard at one point.
It turns out that the thick black and red wires that run to the ammeter have shorted to each other where they ran across a metal edge on the dash structure (see yellow arrow on picture). They were bundled with 3 other smaller wires which seem undamaged. The rest of the loom to the bulkhead I have since dissected out using surgical forceps and super sharp scissors that cut right to the point, in the "Lotus position" (lying on back, head under dash) and the other smaller wires all look OK or salvageable. On the wiring diagram there is a fusible link in this circuit between the main black wire and starter relay in engine bay so assume this failed to work or was too slow to work.
Amazingly most things seem to still work on the car. Since the short was before the dashboard components I am hoping they are all still intact.
Why do they run "neat" bundles of wire across sharp edges? Disaster waiting to happen. People talk of dodgy wires in old cars, I often find the wires themselves to be OK, it is they way they are routed that creates the trouble.
There is always a reason someone sells a car or stops using it. So, I have probably just found out why the '65 New Yorker I have just obtained seemed a bit too good to be true. Was investigating wiring around steering column with a view to converting my reversing lamps to yellow indicators and found burnt insulation. I reckon smoke came out of the dashboard at one point.
It turns out that the thick black and red wires that run to the ammeter have shorted to each other where they ran across a metal edge on the dash structure (see yellow arrow on picture). They were bundled with 3 other smaller wires which seem undamaged. The rest of the loom to the bulkhead I have since dissected out using surgical forceps and super sharp scissors that cut right to the point, in the "Lotus position" (lying on back, head under dash) and the other smaller wires all look OK or salvageable. On the wiring diagram there is a fusible link in this circuit between the main black wire and starter relay in engine bay so assume this failed to work or was too slow to work.
Amazingly most things seem to still work on the car. Since the short was before the dashboard components I am hoping they are all still intact.
Why do they run "neat" bundles of wire across sharp edges? Disaster waiting to happen. People talk of dodgy wires in old cars, I often find the wires themselves to be OK, it is they way they are routed that creates the trouble.
Re: Melty wires to Ammeter
We have all been there.
As Steve said in a previous post, the Ammeter bypass mod is the safety option for most Mopars where all the power runs through ONE Spade Terminal....
As Steve said in a previous post, the Ammeter bypass mod is the safety option for most Mopars where all the power runs through ONE Spade Terminal....
Pete Wiseman; Cambridge.
Mopar by the grace of God
Mopar by the grace of God
Re: Melty wires to Ammeter
Find the ‘madelectrical’ post - mandatory reading. Will sort you out.
( i’d put link but in phone! Just ‘search’)
( i’d put link but in phone! Just ‘search’)
"Cum homine de cane debeo congredi." Woof.
Current Charger status - "Working !"
Current Charger status - "Working !"
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Re: Melty wires to Ammeter
I had mine bypassed when the alternator was replaced/upgraded. Just a dash fire waiting to happen.
-Jon.
Re: Melty wires to Ammeter
Thanks for the advice, I have read that article and in the process of bypassing the ammeter. At least the whole loom has not melted, just the section from the short back to the bulkhead.
Have unwrapped the entire engine bay loom too to work out if anything else melted, seems OK surprisingly.
Only other wire that looks suspect is the one to the heater fan motor, although the fan does seem to run OK. I will probably put a separate fuse in that wire just for safety. Not sure what current that fan would normally pull however. Start with a 5 Amp I suppose.
John
Have unwrapped the entire engine bay loom too to work out if anything else melted, seems OK surprisingly.
Only other wire that looks suspect is the one to the heater fan motor, although the fan does seem to run OK. I will probably put a separate fuse in that wire just for safety. Not sure what current that fan would normally pull however. Start with a 5 Amp I suppose.
John
Re: Melty wires to Ammeter
OR
you make up 2 new wires
and if suspect you take your ammeter apart
you make sure the insulation between the 2 studs and the plate metal backing is in very good order
i.e drill out the holes to twice the size
press in plastic tube
trim flat with small cutting disk
glue fibre washers on either side
shrink wrap the studs
do up first nuts with spiky washers
you locktight the whole thing back together
bolt on the wires with spiky washers tight up against first nuts and slap the threads with epoxy mastic so they never come off again
and then Never put an alternator bigger than 45 amp in the car.....
good for another 30 years
you have a red wire coming into the car from the battery side
it hits a splice in the loom down in the middle where it splits into 3 or 4...all hidden under the tape. basically 4 wires crushed in a crimp and soldered
my wiper switch is in the middle of the dash the splice is near the branch to it and the ciggy lighter. buried deep in the loom
1 bit up to ammeter
1 bit off to the fuse box. covers parking lights and horn + anything else on the NOT SWITCHED side of the fuse box
1 bit into the ignition switch
you have a black wire coming into the car from the alternator
both can be replaced with new wire.
run red from battery to fuse box
take a run to the input to the ignition switch and ammeter just use piggy back spade adaptors
way into car can be made by drilling through the bulkhead connector just pass the wire right through
run a new black from alternator direct to ammeter
job done...
none stick loom tape like orginal https://www.autoelectricalpartsuk.co.uk ... gJM5fD_BwE
Dave
you make up 2 new wires
and if suspect you take your ammeter apart
you make sure the insulation between the 2 studs and the plate metal backing is in very good order
i.e drill out the holes to twice the size
press in plastic tube
trim flat with small cutting disk
glue fibre washers on either side
shrink wrap the studs
do up first nuts with spiky washers
you locktight the whole thing back together
bolt on the wires with spiky washers tight up against first nuts and slap the threads with epoxy mastic so they never come off again
and then Never put an alternator bigger than 45 amp in the car.....
good for another 30 years
you have a red wire coming into the car from the battery side
it hits a splice in the loom down in the middle where it splits into 3 or 4...all hidden under the tape. basically 4 wires crushed in a crimp and soldered
my wiper switch is in the middle of the dash the splice is near the branch to it and the ciggy lighter. buried deep in the loom
1 bit up to ammeter
1 bit off to the fuse box. covers parking lights and horn + anything else on the NOT SWITCHED side of the fuse box
1 bit into the ignition switch
you have a black wire coming into the car from the alternator
both can be replaced with new wire.
run red from battery to fuse box
take a run to the input to the ignition switch and ammeter just use piggy back spade adaptors
way into car can be made by drilling through the bulkhead connector just pass the wire right through
run a new black from alternator direct to ammeter
job done...
none stick loom tape like orginal https://www.autoelectricalpartsuk.co.uk ... gJM5fD_BwE
Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
Re: Melty wires to Ammeter
Thanks for the advice, doing something along these lines, taking pictures as I go.
Have dissected out the whole front loom in engine bay and from bulkhead up to ammeter so I can get my head around what is meant to be going on.
Have isolated the ammeter. Alternator now runs to big connector on top end of starter relay with fusible link.
Really thick wire straight through bulkhead then powers everything on the dash side again with a fusible link.
I have found the splice, I could not work out what it was initially, I thought a set of wires had all melted together, then realised it was meant to be like that!
Any idea how much current the heater fan motor would take in normal use? I ask because one of the wires to that looks as if it has been melty in the past, it is still working however. I would like to separately in-line fuse the motor just to be sure I am on the safe side.
Have also removed long lengths of wire threaded in and out of the frame dangling under the car, rubbing on it, which ran from the electronic trailer brake resistor board in engine bay, to a socket under rear bumper. Whoever fitted that just got it all to work and handed the car back to customer with no thought whatsoever for how long it might or might not last before whole thing shorted out.
Also have a big fire extinguisher ready for the first ignition test after all this is done.
Have dissected out the whole front loom in engine bay and from bulkhead up to ammeter so I can get my head around what is meant to be going on.
Have isolated the ammeter. Alternator now runs to big connector on top end of starter relay with fusible link.
Really thick wire straight through bulkhead then powers everything on the dash side again with a fusible link.
I have found the splice, I could not work out what it was initially, I thought a set of wires had all melted together, then realised it was meant to be like that!
Any idea how much current the heater fan motor would take in normal use? I ask because one of the wires to that looks as if it has been melty in the past, it is still working however. I would like to separately in-line fuse the motor just to be sure I am on the safe side.
Have also removed long lengths of wire threaded in and out of the frame dangling under the car, rubbing on it, which ran from the electronic trailer brake resistor board in engine bay, to a socket under rear bumper. Whoever fitted that just got it all to work and handed the car back to customer with no thought whatsoever for how long it might or might not last before whole thing shorted out.
Also have a big fire extinguisher ready for the first ignition test after all this is done.
Re: Melty wires to Ammeter
You did well to find the splice - I couldnt find mine, so I bypassed and took the main-load engine side with only acc running through the bulkhead at all !
Pop a voltmeter somewhere subtle (like in the ashtray or something) and it'll tell you what going on when you are done. Costs about £3 from ebay.
Pop a voltmeter somewhere subtle (like in the ashtray or something) and it'll tell you what going on when you are done. Costs about £3 from ebay.
"Cum homine de cane debeo congredi." Woof.
Current Charger status - "Working !"
Current Charger status - "Working !"
Re: Melty wires to Ammeter
fan motor will spike up to 30 amps on the instant it starts
i think it will settle down to between 6 and 12 amps, depending on speed setting when running.....fuse for that section will be a strong indicator .
Dave
i think it will settle down to between 6 and 12 amps, depending on speed setting when running.....fuse for that section will be a strong indicator .
Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
Re: Melty wires to Ammeter
Thanks, will definitely put a fuse in there.
Powered the dash up today, indicators worked, headlights worked, without any smoke. However I had replaced the indicator flasher relay with one of the solid state ones that flash on a fixed time interval. The indicators worked for a few seconds and then just stayed on + burning smell; the semiconductors getting hot type, not melting plastic type.
Opened it up and it just has a transistor and a few other bits inside, which had melted. Put ancient original bimetallic strip one back in and flashed away no problem.
There is a another type of timed flasher relay that has a timer circuit and an actual physical relay inside, which I have used in other cars with no problems. Have just ordered one of those instead.
The websites always say there are 2 types of flashers; old school bimetallic strip relays and modern solid state. In fact there is also another type i.e. solid state timer operating an old school relay (which is probably more resistant to burning out if current draw is not exactly within spec).
I like the timed ones as when I alter the rear bulb wiring to create separate rear indicators, altering the total number of flashing bulbs in the process, the flash rate should stay normal.
Powered the dash up today, indicators worked, headlights worked, without any smoke. However I had replaced the indicator flasher relay with one of the solid state ones that flash on a fixed time interval. The indicators worked for a few seconds and then just stayed on + burning smell; the semiconductors getting hot type, not melting plastic type.
Opened it up and it just has a transistor and a few other bits inside, which had melted. Put ancient original bimetallic strip one back in and flashed away no problem.
There is a another type of timed flasher relay that has a timer circuit and an actual physical relay inside, which I have used in other cars with no problems. Have just ordered one of those instead.
The websites always say there are 2 types of flashers; old school bimetallic strip relays and modern solid state. In fact there is also another type i.e. solid state timer operating an old school relay (which is probably more resistant to burning out if current draw is not exactly within spec).
I like the timed ones as when I alter the rear bulb wiring to create separate rear indicators, altering the total number of flashing bulbs in the process, the flash rate should stay normal.
Re: Melty wires to Ammeter
yeah you have
old flasher bi metallic for bulbs
new solid state flasher for bulbs
new solid state flasher for LEDs
old flasher bi metallic for bulbs
new solid state flasher for bulbs
new solid state flasher for LEDs
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying