Hi, my alternator on my 1990 Ford 460 no longer charges my battery and I cannot figure out why.

I will try to describe my problem and the steps I took to fix (make it worse ) it.

First off, my vehicle is a 1990 RV with a Super Duty chassis and a 460 engine.

So my problem started like so: At one point, when I was parked at a grocery store, my starter relay (solenoid) clicked once and did not turn the starter over. So I just figured I'd spend the night there and try to fix it the next day. I didn't know what the problem was, at that point. The next day, as I woke up, just for the hell of it, I tried starting it again, and it started as if nothing had happened. So then I just hit the road and continued on my trip.

Only a few hundred kms later on the same trip, as I stopped for gas, it did it again. So from that point on, I began starting it by shorting the starter relay. and roughly 1400kms later, still on the same trip, I finally replaced the starter relay. and drove it for another 3000kms without problems.

And then, another problem came up. when I tried to start it, the engine would start but the starter kept cranking even after I turned it off. The only way to stop the cranking was by disconnecting the battery. So, I replaced the starter relay again and I also replaced the starter itself since it was from 1990 and I did not wanna have to worry about the starting ever again. Big problem though. After I replaced the relay and the starter, the alternator would not charge the battery anymore. And it cannot be just a coincidence. I must have reconnected something wrong. But I checked everything and it all seemed fine. So I checked the battery (fully charged with the engine off, it sits at 12.6V) and it's all good. For the hell of basically having all new components except the alternator itself, I also replaced the Voltage regulator. Did not fix the problem. There is a few fusible links in the system, but I am not sure how to check them because my multimeter does not reach both ends of the wires. A little hint how to do it? I also cleaned up, sanded and greased (electrical grease)all my wire endings.

- how do I check if the problem is the alternator itself (and knowing for sure it's the alternator and not the wires or the fusible links)?

My alternator wiring is as follows: My BATT terminal on my alternator has a big (prob'ly 8-10ga) red wire going to a weird blue box (looks like a car aftermarket sound system's amp). Here is a picture of that blue box

. Out of the blue box is a Green wire (same size as the red one) and a black/blue one that is slightly smaller prob'ly 12Ga)The green one is connected in a marette located near the alternator to a black and yellow one that goes into the starter relay (solenoid).



If it's not the alternator, what could it be? And is it just coincidental that it stopped charging the battery up right after I replaced the starter?

Thanks in advance for the help.

 

I also forgot to mention that my starter relay still only does the click once without cranking the starter, so I still have to hotwire it to start the engine (not related to my alternator problem?)

And does the starter relay have a ground wire? if so, on which post is it?

 

The starter relay grounds through its mounting ears.
Take it off and sandpaper a little spot behind each. Grease to keep corrosion away.

No comment on why you need to jump your new solenoid except that if it has welded itself closed before it is all pitted on the contacts.
Given that you have changed the starter I would look at the block ground connection. If poor it will cause excessive amperage to overheat the solenoid contacts and weld them together. This is why it won't stop cranking.
Next time give it a whack before pulling the battery cable. If might just stop.

 

Check voltage while running.
It should be 14+.
If so the alternator is charging.

All wires should be connected to the same stud as the battery cable.
Only the starter cable connects to the other side.

 

The blue item is a DUAL BATTERY MULTI ISOLATOR and it will charge the house battery with the engine running.
Make sure that black wire with an orange stripe (the one the green wire is hooked to) is on the battery side of the starter relay or the alternator will not charge.

 

Thanks for the replies, guys. I will take the alternator to the shop to get it bench tested because it is deffinitely not charging up the battery. When the engine is idling, there is no difference in battery power (it remains at 12.59volts). If there is any other way to check if my alt is not working properly, please let me know. Thanks.