3G not charging... ????

[BLOWN 5.0 FOX]

I took my car out for its maiden voyage... and it ran the balls!!

Right before I got to the gas station.... it started to buck and the rpms gauge was going nutty!!

filled up thinking i might be low on gas, started the car----- click click....battery was dead (been sitting for a few months) got a quick jump and was on my way. When I pulled out the car had no power and had a hard time keeping it going at 1500-2k rpm. pulled over and called my buddy, charged it for 10min with his truck and again, off it went, this time, no issues. I drove it right home.


When I got it home , I did battery test: GOOD BUT RECHARGE 330CCA on 600CCA Batt, and the voltage was at 11.4V.

Tested the alternator- came up with "high ripple current detected" with an output of just 9.8V.

what the duece???

I am wondering what to do next to determine the failure.

background:
Its a 3G alternator, ran fine last year.

this year it got a new motor/blower. same alternator and wiring has not been changed or is not connected (double checked). Any input would be excellent as I dont want to simply throw in a new 3G for the fun of it.


Thanks guys- I cant wait to get the bugs figured out this thing is MEAN

 

[LaserSVT]

I took my car out for its maiden voyage... and it ran the balls!!

Right before I got to the gas station.... it started to buck and the rpms gauge was going nutty!!

filled up thinking i might be low on gas, started the car----- click click....battery was dead (been sitting for a few months) got a quick jump and was on my way. When I pulled out the car had no power and had a hard time keeping it going at 1500-2k rpm. pulled over and called my buddy, charged it for 10min with his truck and again, off it went, this time, no issues. I drove it right home.


When I got it home , I did battery test: GOOD BUT RECHARGE 330CCA on 600CCA Batt, and the voltage was at 11.4V.

Tested the alternator- came up with "high ripple current detected" with an output of just 9.8V.

what the duece???

I am wondering what to do next to determine the failure.

background:
Its a 3G alternator, ran fine last year.

this year it got a new motor/blower. same alternator and wiring has not been changed or is not connected (double checked). Any input would be excellent as I dont want to simply throw in a new 3G for the fun of it.


Thanks guys- I cant wait to get the bugs figured out this thing is MEAN

When you say tested, do you meen a bench test, or with a meter with the car runing? Throw out a couple things, did you fuse your wire? If so hows the fuse and connections. Check to see if your excitor wire is hooked up. Is the alt making any bearing noise?

 

[jrichker]

High ripple current usually means one of the diodes inside has gone bad. Time for a replacement alternator unless you are really into tearing the alternator all apart and replacing the diode.

 

[LaserSVT]

High ripple current usually means one of the diodes inside has gone bad. Time for a replacement alternator unless you are really into tearing the alternator all apart and replacing the diode.

Yah, what he said

 

[BLOWN 5.0 FOX]

i agree on that one- luckily I had it made custom for me at a local electrical systems shop, lifetime warranty. It was nice to see them test it right in front of me but I guess parts do fail. Ill yank it off and have them check it over. THANKS

 

[stykthyn]

I had a diode crap out a month ago. I turned on my A/C for the first time this year and the little needle on my batt guage plumetted like a rock.

 

[BLOWN 5.0 FOX]

Call it a hunch, but I want to double check my wiring skills (circa 2 yrs ago when I did the swap)

Ive searched out the procedure and all, but there seems to be clear pictures of before and afters, but not durings!! I cant confirm if my wiring is correct as compared to the instructions.
I am having my alternator sent out tomm to be tested, but for now, give me your .02....

my factory harness has cut 2 cut wires:
the black 10awg
yellow/white tracer

my 3G is wired as follows:
white with black tracer to stator spade (on alternator)
yellow with white tracer to charging post
green with red stripe to factory green with red stripe

I have a 4awg on the charging post that has a 175A fuse 2 ft away, which then goes to the shutoff switch on the trunk.

For some reason, memory has not served me right and I dont remember where I got this wiring scheme from, but I do remember following some sort of schematic, which does not match any on this forum. (?????)

Let me know if my wiring is lagit- then I can feel 100 % on the alternator diodes when I speak with the electrical shop tommorrow.

 

[BLOWN 5.0 FOX]

found the link!!! heres my setup. The only hidden wire in the loom is the green with red stripe.
http://fordfuelinjection.com/?p=75
Anyone?

 

[jrichker]

For a battery cut off switch, see http://www.moroso.com/catalog/categorydisplay.asp?catcode=42225
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 http://fordfuelinjection.com/?p=7 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 power
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
http://www.veryuseful.com/mustang/tech/engine/ 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..

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.

 

[HISSIN50]

Cool stuff from JR.

I'd also reconsider the fuse - that 4 AWG charge cable should be rated for much less than 175 amps. WIth a long cable like that, the possibility of an issue goes up exponentially IMHO. I'd fuse it 'tightly' (tailored for the weakest link in the system) if you can.

 

[BLOWN 5.0 FOX]

I am going to rewire my car per the moroso setup. I currently am using a porsche factory provided Hella shutoff, its cheasy but it has a removable key which is a bonus for me for car theft at the track etc. Anyone know of similar setups with removable keys in the batt shutoff switch?

Also- what did you mean about the 175A fuse? I was mistaken when I said I had 4awg, its actually 2awg made by Taylor, came with the trunk mount kit.....

Do you think the 2awg is too suficient?
I plan on running the 2awg to th starter solenoid than still using my 1/0 cable to the rear.

Thanks guys

 

[HISSIN50]

I am going to rewire my car per the moroso setup. I currently am using a porsche factory provided Hella shutoff, its cheasy but it has a removable key which is a bonus for me for car theft at the track etc. Anyone know of similar setups with removable keys in the batt shutoff switch?

Also- what did you mean about the 175A fuse? I was mistaken when I said I had 4awg, its actually 2awg made by Taylor, came with the trunk mount kit.....

Do you think the 2awg is too suficient?
I plan on running the 2awg to th starter solenoid than still using my 1/0 cable to the rear.

Thanks guys

If you have a 130 amp alternator, I'd probably run something more like a 150 amp fuse, given the distance the power runs (from the alt to the battery in the trunk). All in all, it's not a big deal but if something ever goes wrong, you won't second-guess yourself that an electrical fire could have been lesser had a smaller fuse been used. The nature of slow-burn fuses is they they take a bit of time (depending upon the severity of the short) to burn anyways.

Jrichker's thoughts might vary from mine. It has been some years since I had a trunk mounted battery.