I've got a 89 saleen and i've been having alot of work done to it. It is finally done however the car won't charge. The alternator I had in it was an overhauled 130 amp which apparently went bad. So, put another one in, that was bad. Put another in, this one works(confirmed on bench) but it still won't charge in the car. Checked all associated chassis wiring, all checked good. Tried eliminated the chassis harness all together and still no joy. So, decided to try a one wire alternator. Same problem. :bang: Has anyone come across something like this and do you have any suggestions. I NEED HELP. The only other thing I can think of is Electronic Specialists and I don't have the money for that NOW. Please help

 

You probably would have had the money for proper diagnosis if you hadn't kept buying more parts. :bang:

 

Gonna try but, not sure it will help.

I had a similar problem on a 1983 Buick Regal

In this instance I use a 12 volt test light.
(Looks like a pointy screw driver with a light in handle and a wire attached to handle}
On the back of the alternator there was a big red wire
I tapped into it with the test light and got no light.
Thats putting the clip on a good ground and sticking the needle looking end into the bid red wire on back of alternator. (KEY ON)

That big wire on the back of the alternator goes to the postive post of the battery.
Of course I am talking about a GM product here.
But it would be my guess that a ford is not much different.

In my case a previous owner had spliced the wire back together poorly.
Thus every time the battery shifted just a slite bit it caused a no charge situation.

The point is a 2 or $3 test light can tell you a lot when looking for an all out short circuit.

Basicly you test each end of same wire for juice.
If they are different than go to the middle of wire.
than imagine a new mid point from the original.

To put the mildly I find it a very valuable tool.

The light don't lie.................

Not sure this will help
since you say wires were replaced?
bad plug at altenater? maybe?

Oh one more. but. since you bench tested it its not likely.

When I was rebuilding an alternater once I used a straightend out paper clip to hold the brushes in while putting it back together.

I put back it back on car and got NO charge.
Well until I removed the paper clip.
Felt like a dufous but, never forgot the experience.

 

This may sound like a stupid question but often its the little things we over look...is the battery itself ok? Maybe the alternator is charging but the battery is not holding it.
A test light is the best tool to use in any wiring or electrial system problem as the first tool for diagonsing the problem.
Also for about $50 they sell hand held tools that not only load test the battery but also test your charging system and some can even tell you how many amps your alternator is giving out.

 

If the alternator is functional, and assuming that the battery is okay, have you checked the voltage regulator? Also, keep in mind that if when any of these three items fail, they have a bad habit of taking one, or both of the others with them. So, if you replaced the alternator because it failed, now would be a good time to look at the battery and voltage regulator.

 

if the battery works than it has to be either the battery, regulator, or a short somewhere. question, have you had the car running??? boost it if you have to, and see if it will run. Afterwards, check and see if and what the charge is on the battery. Not sure how much more to tell you. keep us posted.