Battery Relocated...starting issue...

stock didn't have a fuse from the battery to the solenoid, so why try to fuse this one? everything else connected to the solenoid is fused or has a breaker/relay.

i'd remove the fuse

bypass it, for giggles. have a fire extinguisher with you. see if it fixes it without a fireworks show in your trunk.

all i'm saying is, if it didn't come from the factory like that, why mess with it?

I originally had a 200 amp in-line fuse but ended up deleting it with no problems. I had put my fuse in the fenderwell using an audio distribution block. I have had no problems after removing the fuse.

I'd get rid of the fuse and wire the system so the ground wire is the long one from front to back and the positive wire and solenoid are in the trunk. It's more work, but makes for nice reliable starting since the Positive wire is only about 3 feet long instead of 10.

Remove the fuse, it's pointless, i fail to see the safety value of it at all.
Each circuit on the car has it's own fuse anyway.

Ditch the fuse

Here's the correct way to do it...

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..

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.

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

I understand your reasoning for the fuse, you have about 8ft. of 4ga (or larger) running through your vehicle. If it should happen to short anywhere along that 8ft, chances are good you'd have a nice fire before you could unhook the wire from the battery. (The unfused factory posative wire is much shorter than the one running to your battery and dosent lay against the body of the vehicle for any distance.) Sounds to me like your first start with a new fuse is enough to make the fuse begin to blow, then the second attempt finishes it off. Try using a circuit breaker. Or a "slow blow" fuse if you can find one that big. Until your starter motor starts spinning, when you engage it, for a split second it puts a huge load on your electrical system. (Maybe more than 200 amps) The Circuit breakers usually trip a little slower than fuses blow, but will still protect your system in case of a short. To make sure that the fuse is actually the problem you can jumper it, but as has been stated, have a fire extinguisher handy, just incase you do have a short.

Dont have a part# on hand but I worked in car audio shops for a while and we used the breakers all the time. If you have a Circuit City, Best Buy, or local install shop, maybe even Radio Shack, one of them should have one. The other thing about the breakers is if they trip, you just reset 'em you dont have to spend money on a new fuse every time. If you cant find one, let me know and I'll see what I can do to find one online.

Hmmmm.... still not sure why you feel you need a fuse for the starter cable....

Ditch the fuse!

Cobra912 said:

Hmmmm.... still not sure why you feel you need a fuse for the starter cable....

Ditch the fuse!

Click to expand...

I've seen an un-fused 4ga with a dead short, it's like a cutting torch on sterrorids, but in this case it would run from your trunk to under your hood. Error on the side of caution...