Hey.

What alternator came stock in a 79 F-150 Reg. Cab long box. 302 w/c6.

65Amp or 70Amp ?

I need to know because I can get either one for 35$ at wreckers, but I can get a new 65amp for around 70$. The 70Amp new is 140$. SOO if its 65Amp then I will just get a new one, if its 70 then I'll get used.

Is it just one size for that truck or could it be more then one? If so how can I tell the difference. (keep in mind even though its a nice day its still cold so the less time standing under the hood the better ;-)


CK

 

Ford alternators usually have a part number and amp rating stamped in the case. You may have to scrap some crud off to read it.

 

Ok new problem.

I changed alternator and I've still got the alt. light on.

Now, I'm going to just be sure that the thing wasn't dead (since it sent back as a core now can't prove one way or another) but the thing is the three things that attach to the alternator aren't on all that good.

The first one (red one) has an insulator thing and I can bolt it on no problem.
The other 2 are just clips and they aren't staying on.

Is one of those wires telling the light inside to shut off and maybe its not attached...or?

Also how tight should the belt be ?

It's not tight enough that it has no give, it has a little give but not much....

C

 

All connections should be tight, Period !

 

Thanks for stating the obvious!!!

I guess a better question would be to ask you how to get those to stay connected better. Should I cut the wire and crimp some new ends on (I dont have any thing to do that with guess radio scrap would have it?)

Thats kinda what I wanted to know.

I also wanted to know if my alternator is charging hte truck based on that one wire...or if their is no way to know until I find it doesn't start one day ;/


CK

 

The Fld terminal must have voltage on it or the alternator will not put out any current. This is an easy check to find out if the alternator is ok. The regulator supplies voltage to the Fld, short for field.

 

Ok. **Begin pride sucking in here*


I have no idea what you mean.

Going off of what I took apart.

Their are three terminals (btw they colours are in different spots on the new boshe one as opposed to old one, guy at part source told me to use same location and disregard the colours) I hooked the one terminal up that was a circle (meaning I had to unscrew something slip it over, put screw back down) That was the top most one. The one right beside that but down a little sort of slipped over it just had a rubber cap with a copper ring inside and I couldn't get it back on nice. I think tomorrow I am going to try and use some needle nose to straighten it to see if that makes a difference.

Then the last terminal down closest to the engine has the same type of rubber cap ring thingy and its not on well either.

Now are these standard connectors? Is their something else i should do other then trying to straightn the copper/brass (whatever) connectors inside and sliding them over the screw as they were on the old one?

The slide on doesn't make half as much sense as the nice screw on ones but whatever.


*end of sucking up pride*

Thanks in advance,
CK

 

The big wire with the eye terminal and the nut is the "hot" wire to the battery. Actually it goes to the battery terminal on the starter solenoid through a fusible link. The other slip-on connecters go to the field and stator terminals. The field connection is the one to make sure is good. The copper ring can get bent out of shape and you can bend it back into shape to hold better. If the regulator isn't supplying voltage/current to the field it won't charge. One quick test to see if the field is energized is with the engine running hold a screwdriver near the rear bearing on the alternator. If it's magnetized, the field is energized and it should be charging. If it's not, look at the regulator or the wiring.
Hope this helps.
Greg

 

I know it's too late for this now (since you've already sent your old Alt back to the store), but...

Most battery specialty stores (around here it's Battery Warehouse), and many parts stores will test your alternator for free. It's a shame the store you bought your new one from, didn't test the old one if it turns out the problem was only in the wires.

 

The easiest way to know for sure if the alt is charging is to use a voltmeter. Touch one contact to the + bat post and one to the - bat post. If charging, it will read about 13 volts or higher - if not charging, it will read about 12 volts or lower.

The last time I had trouble with mine not charging, it was the regulator (box between battery and radiator), luckily I had a used one in the tool box. But like you, I assumed it was the alt, so I had bought a new alt for nothing.

With those loose connectors I've had to use some pliers and lightly squeeze them so they hold tighter to the bolt. Might give that a try. Carefull not to squeeze to hard - it's tough to 'unsqueeze' them...

Marty

 

macguyver that cleared up my prior confusion, exactly what I wanted to know.


I think its the alternator because the alternator light came on and, getting the wires off was difficult I think I bent the insides myself when pulling them off with pliers (they were on well enough I couldn't just yank off by hand, but I had no idea that the insides were so senstivie so I think thast that)


But ya I thought they should of tested or something to, but he just stuck it in the box my new one came in and gave it to me.




Now I am HOPING it wasn't the regulator.

Did the ALT light come on in truck when that was dead? I assume it would since regardless no charge was getting to teh battery correct?

 

Ok,

so just had a few minuites and I went out to pull the alternator out and tripe check those connections.

They are all on their good now and aren't going anywhere.

Light is still on

So, I'm going to take a stab and say I spent 80$ for no reason on this new alt. well its nice and new ;/ I am kinda hard up for cash atm and that sucked.

Now.

I'm going to try some of the tricks you guys said for seeing if the alternator is charging the truck before I go further.

Maybe the light is just messed up (ya right)

So if its the regulator hopefully thats not expensive


CK

 

Charging circuit

[IMG][/IMG]

 

Do you have a bigger picture of that? Even on my 22" monitor I cant read all the print.

I have replaced the alt. And my girlfriend was kind enough to goto Partsource and get me the regulator today (it was only 20$ so I figured since I'm already down 80 may as well try this as well) so I am going to install that tomorrow.

If thats not it I may just rip it all out. Run brand new wire to it all and hell replace the screws while I'm at it.

This truck is my project truck now since I have nuff cars for my whole family lol. 2 on the road.

Thanks for all the help guys I wouldn't even of had a clue to try the regulator had you not mentioned it.

CK

 

Regulator was the problem.


So I've got a new regulator and a new bosch alternator in their and its working like a charm.

Only thing that I was curious about is the wires that come out of the regulator have one that goes about 4" and just ends..it has a cap looking thing on it. Any idea what that would hook up to?

If you guys have no idea what I'm talking about I could take a picture and post it... Just curious I've got all the time in the world with this truck so if its not supposed to be like that...


CK