Almost had a fire need help please!!

[KyleEBK]

Ok so jsut got my car back from the body shop the other day been having problems with it starting , when he wroked on it the battery got drained well it charged back up and ahs been working fine for a couple days

well iw ent to start my car 30 mins after i drove it home from work ( 7 minute ride) and i get no crank jsut the solenoid buzzing and hear this crackling so i try it again with same results then look back in my hatch (where battery is) and see buncha smoke so i rushed back there and the things that connect to the battery post melted right through on the negative and positive side and there was molten metal on my carpet

so i tried another battery and had a buddy hold it on there and it smoked abit again and he pulled it off less then 1400 miles ago last october i got the solenoid ,alternator and starter replaced

whats goin on here? is there a way to isolate a short? i have a digital multimeter and a test lamp. it was only sparking and smoking when i tried cranking

help please!

oh i also put the DMM parralell between battery + cable and + post on battery and it read same voltage as puttin it on negative and positive post on battery, is that normal?

 

[KyleEBK]

i talked to the mehcnaic that replaced the starter he said it may be the ignition box or starter or solenoid, he said try to bypass the solenoid to narrow it down a lil more

anyone know how to do that? should i jus buy another solenoid and try that? im thinking the starter is bad and shorting out inside it,

they cant look at it till wednesday man this stuff is a headache its always soemthin else with this car

 

[BlownFiveLiter]

What gauge cable did you use when you relocated the battery to the rear? Also, how clean are all your attachments (positive and negative). I had a negative melt off at the battery before, but I also had a bad cable that was full of resistance. Using too small gauge of cable could have the same effect when the wire gets too hot.

 

[jrichker]

For a battery cut off switch, see Moroso : Category Display
is the switch http://www.moroso.com/catalog/images/74102_inst.pdf is the installation instructions.
Use the super duty switch and the following tech note to wire it and you will
be good to go.

Use the Moroso plan for the alternator wiring and you risk a fire. The 10
gauge wire they recommend is even less adequate that the stock Mustang
wiring.

There is a solution, but it will require about 40' of 18 gauge green wire.

Wire the battery to the two 1/2" posts as shown in the diagram.

The alternator requires a different approach. On the small alternator plug
there is a green wire. It is the sense lead that turns the regulator on when
the ignition switch is in the run position. Cut the green wire and solder the
40' of green wire between the two pieces. Use some heat shrink to cover the
splices. See Ford Fuel Injection How To Solder Like a Pro for some excellent
help on soldering & using heat shrink tubing.

Run the green wire back to the Moroso switch and cut off the excess wire.
Try to run the green wire inside the car and protect it from getting cut or
chaffed. Crimp a 18 gauge ring terminal (red is 18 gauge color code for the crimp
on terminals) on each wire. Bolt one ring terminal to each of the 3/16" studs.
Do not add the jumper between the 1/2" stud and the 3/16" stud as shown it the
Moroso diagram.

How it works:
The green wire is the ignition on sense feed to the regulator. It supplies a turn
on signal to the regulator when the ignition switch is in the Run position. Turn the
Moroso switch to off, and the sense voltage goes away, the voltage
regulator shuts off and the alternator quits making power.

The fuse & wiring in the following diagram are for a 3G alternator. The stock alternator uses a dark green fuse link wire that connects to 2 black/orange wires. Always leave them connected to the starter solenoid even if you have a 3G alternator.

See the following website for some help from Tmoss (diagram designer)
& Stang&2Birds (website host) for help on 88-95 wiring
Mustang FAQ - Engine Information Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg


Rear mounted battery ground wiring. Follow this plan and you will have zero
ground problems.

One 1 gauge or 1/0 gauge wire from battery negative post to a clean shiny spot
on the chassis near the battery. Use a 5/16” bolt and bolt it down to make the
rear ground. Use a 1 gauge or 1/0 gauge wire from the rear ground bolt to a clean
shiny spot on the block.

One 4 gauge wire from the block where you connected the battery ground wire to
the chassis ground where the battery was mounted up front. Use a 5/16” bolt
and bolt down the 4 gauge engine to chassis ground, make sure that it the metal
around the bolt is clean & shiny. This is the alternator power ground.

The computer has a dedicated power ground wire with a cylindrical quick connect
(about 2 ½”long by 1” diameter. It comes out of the wiring harness near the
ignition coil & starter solenoid (or relay). Be sure to bolt it to the chassis ground
in the same place as you bolted the alternator power ground. This is an
absolute don’t overlook it item for EFI cars
Note: The quick disconnect may have fallen victim to damage or removal by
a previous owner. However, it is still of utmost importance that the black/green
wires have a high quality ground..

The screwdriver points to the common body ground for the alternator, battery and computer.

Picture courtesy timewarped1972

Crimp or even better, solder the lugs on the all the wire. The local auto stereo
shop will have them if the auto parts store doesn't. Use some heat shrink tubing
to cover the lugs and make things look nice.

 

[KyleEBK]

im running 4 gauge wires to battery i drove it all last year without any real problems cept the starter seized up and before that solenoid went to hell and i added new 3 g alt the loops on the battery terminals melted right off on both sides and made a puddle of molten metal which almsot caused a blaze

times like this made me wish i woulda jsut boguht somethin newer however when its running right i have no such thoughts


I upgraded all wiring when i did 3 g swap and wiring has been fine for a year almsot now i think i have a serious short or soemthin i dunno i dont have a battery cutoff switch but i am running large fuse between alt and solenoid

 

[KyleEBK]

after really looking at that diagram thats basically the one i used a year ago to hook it all up, i have my alt ground going to common ground with computer and such

im just running 4 gauge in place of the 0 gauge which i dont think would make tat much difference I do have 0 guage left over from my 4500 watt rms stereo in a previous vehicle but i dont think its gonna make that much difference

tommorow i have off and i am going to try short wires from a battery straight to solenoid to make sure it isnt my positive wire running all the way back to hatch and also make sure it isnt a bad ground back in the hatch area, i never thought to check ground in hatch so im gonna be looking at that tonight yet i think

 

[95Vert383AOD]

Check the solonoid....They can either go the good way or the bad way. Had an old 83 towncar once and the solonoid stuck and literally melted the wire between the battery and solonoid. Just an idea if its not so new.

 

[KyleEBK]

well i checked my hatch ground and it looks terrible in my opinion

its grounded to where the roll cage is bolted to the hatch floor and it looks like theres paint on it yet too
wheres a proper place to ground it in the hatch? i was thinkin maybe ill run a 4 gauge wire from the engine ground in front straight to the battery negative, that would be if i cant find a good spot to ground in the hatch i guess

so as of now im charging up 2 batteries the one in the car was at 12.36 volts and 70%

tommorow im gonna try short wires to a battery outside the car instead of using long positive cable and poor ground in back and see what happens,,, anyone know what this mechanic was tlakin bout when he said bypass the solenoid? is that evne possible? the solenoid is less then a year old

the smoking and sparking only happened when tryna crank the engine( which didnt crank just solenoid buzz) I also forgot to mention that the positive battery cable was jigger rigged and semi loose (positive post was missing on battery and just used a long bolt with buncha washers to make it somewhat tight) could this cause such an issue???

 

[ID89GT]

Well if its only doing it when you crank then its gotta be between the solenoid and the starter. Try a different solenoid and if it still does it have the started tested.

 

[KyleEBK]

K i will just buy another solenoid they arent very expensive and give it a try and if it does it then i know its prolly the starter huh,

as far as getting the starter tested, not sure if thats gonna be possible i dont have a jack or jackstands here and not able to get udnerneath the vehicle without such things so wont be able to take it off and take it to autozone

 

[jrichker]

after really looking at that diagram thats basically the one i used a year ago to hook it all up, i have my alt ground going to common ground with computer and such

im just running 4 gauge in place of the 0 gauge which i dont think would make tat much difference I do have 0 guage left over from my 4500 watt rms stereo in a previous vehicle but i dont think its gonna make that much difference

tommorow i have off and i am going to try short wires from a battery straight to solenoid to make sure it isnt my positive wire running all the way back to hatch and also make sure it isnt a bad ground back in the hatch area, i never thought to check ground in hatch so im gonna be looking at that tonight yet i think

The wire size is important. Too small wire will cause voltage drops and hard starting. The slower the starter turns, the more current it pulls. More current means more heat and more voltage drop. It is a vicious circle.

 

[KyleEBK]

alright progress update went to autozone bought solenoid 2 battery clamps i put in new solenoid and ran 2 short wires to a battery on a chair outside the engine compartment

now the car is cranking but not starting so now im in a whole nother list of problems

JRichter - In lieu of your advice I will be running 1/0 gauge wiring from front to back im going to make 2 runs. from positive of battery up to the alternator + post and im going to make a run of it from engine block ground straight to battery negative

so now im bringing out the DMM and going to follow the crank no start list, anyone have an idea of what could be the problem now after my serious short yesterday?

the type of solenoid i boguht from autozone is different then the one that an autoshop put in the car I have no wire on the I post of the solenoid.... could this be a problem? i hooked i up the way the previous one was hooked up..

 

[Cobra912]

The wire size is important. Too small wire will cause voltage drops and hard starting. The slower the starter turns, the more current it pulls. More current means more heat and more voltage drop. It is a vicious circle.

Exactly! I had the same thing happen when I relocated my battery I used 4 guage and almost burnt my car down. The battery actually boiled and I had to take it out with gloves 4 hours later it was so hot to the touch!!!!

I put in proper 0 gauge and have never ever had a problem since!

 

[KyleEBK]

another progress update

CAR IS RUNNING, i forgot to hook a wire onto the positive side of the solenoid, a medium size blue one and it fired up so im thinking the shrot may be in my wiring from solenoid to the battery that was in rear hatch

i think it may have been pinched when the body shop guy lifted the car to work on it... not sure, im gonna run new wires now.... thanks for all the help throughout my ordeal soon i will post pics of new paint job .. black with cardinal red pinstripe through moulding

 

[KyleEBK]

After removing the wire i inspoected it and it appears to be intact

I installed 1 run of 0 gauge from the starter solenoid to the positive on battery and tried the vehicle, no start which leads me to believe the main cause of this problem was a bad ground, so i ran another run from the negative on the battery up in the front to a bolt on the fender wall

starts right up, i feel safer knowing my electricals are up to par and strongly suggest anyone running abattery in the rear to use 0 gauge wire and make sure your ground are very good! or risk the possibility of your car burning up like mine almsot did