I'm having electrical problems non-stop and don't know where to go from here. It all started back in the summer with the brand new battery not able to hold a charge, had it tested and it was good so now I've put in a new alternator, starter solenoid, and voltage regulator and it still is having these problems, the truck still will only start once and the battery won't have enough juice to start a second time and now the latest issues was today after I put in the new voltage regulator I hit the defrost and the radio lights went crazy and wouldn't turn on after that and the wipers started working super slowly then a mile later everything on the dash that's electrical went out, all gauges zeroed out as if the battery was not there and the lights don't turn on now. I'm at a total loss as to what would be the issue this time. I'm not sure on the fuse block yet because when I got back if I'd have done any more work I'd have stuffed it with tanerite and blown the thing sky high.

Any ideas? I've tried the new alternator and voltage regulator like what was mentioned in my last thread and I tried a test light as well with the negative cable off and it wasn't drawing any current with the truck off so it's something that's not working right with the truck on.

The new alternator is a 60 amp alternator if that matters. That's what I was told would work but it doesn't seem like that if I can't run a radio, wipers and defrost at the same time.

 

You said you replaced the starter solenoid, a new one i would guess ? How about the starter it self ? Does it get hot when you crank it over ? It could have a short in it and dragging it down quickly . Just throwing some guesses out there to you,i can't think of any others right now.

 

Sound like you have a ground wire problem. Make sure battery cables are clean and tight. Neg side battery cable goes to engine block. Not a bracket near by, but the block itself. Scuff the paint off the block if necessary for good contact. Clean the positive cable going to the solenoid, and at the starter plus the other wires that attach to the solenoid. Double check that the starter bolts are tight. If your still having problems, Get some 8 gauge cable. You can buy it different lengths with eyelets already crimped on. Its similar to battery cable, just smaller diameter. Get a measuring tape and take note how many cables youll need. One cable from block to frame. One cable from cab to frame. You can also attach 14 guage wire from neg side of battery to inner fender and from frame to bed. Adding grounds with better wiring is much easier, and more effective than trying to resurrect the old 16g-18g wiring.

 

Ground connections are my next check then. I had a discussion with a friend who had similar issues with his 78 and said it was grounds for him. He said he though there was 4 ground, two on the block, one on the cab and one on the bed so I will dig into that tomorrow if I can find a dry place to work, it's been raining and is supposed to freeze and turn to snow tomorrow, gotta love Minnesota fall weather.

Jim - It has a new starter as well. I replaced that this summer, I'll check if it gets hot tomorrow.

Off subject but what is the correct amp for an alternator? I've heard of people putting in 100 and even 200 amp alternators for having aftermarket stereos. I'm not sure of what's in my mustang since I didn't check when I bought the new alternator last year but I have an aftermarket sound system in it and haven't had any problems with it so far.

 

likely you have a 60a alternator which was stock. I have an amp, cab lights, and 2 driving lights. About the only time the alternator cant keep up is if the lights, heater and wiper blades are on, at idle. If you decide to upgrade the alt., install a heavier wire on the charge back (bat terminal) on back of the alternator

 

There is a fusible link between the alternator output stud and the battery side of the starter solenoid. Make sure this has continuity. Disconnect the negative battery cable before doing this. Once the negative battery cable is hooked back up, measure the resistance between the mounting studs of the voltage regulator and the negative terminal of the battery.

Make sure you actually use a multimeter for these two tests. Do not guess based off how things look visually. You cannot diagnose electrical problems without the proper tools.

A 60 amp alternator is just fine for a stock electrical system. If you are seeing otherwise, then there is a problem with your charging system. But you already knew that.

 

I am going to redo the grounds since I'm pretty sure that's what it is now. I hooked the battery back up today and the engine started turning over without the key in unless I hooked up the positive cable first. I have checked that fuse already and it seemed fine.

While I head out to get some ground wire can anyone tell me where they are located usually to save some time looking? I've been told two on the block, one on the cab and one on the bed.

 

Also reach up behind the dash and grab the ignition back and wiggle it and give it a few yanks some will start to fall apart from the back side.

 

I don't understand how you can know what the problem is if you have done zero troubleshooting to find out.

This is likely a separate issue that is not related to your charging problem.

What fuse did you check? Are you talking about the fusible link I mentioned (not a fuse)? When you say it "seemed" fine that implies you did not use a multimeter, which means you actually don't know if it's fine (something I specifically advised against in my previous post).

But, keep trying to figure it out your way, it has worked for you this far

 

I will check the ignition, never thought of that.

I pulled off the negative cable that goes to the block and that was nicely corroded so I wire wheeled it and the eyelet and put that back on but for the life of me I can't find the grounds for the cab and bed. I wasn't able to get to town to get the wire today but I think I will just it tomorrow. Will the ground from the battery to inner fender work for the cab ground or is that just an extra ground?

 

Yes the inner and the cab bolt directly together the frame needs a ground because of the rubber bushings, But you can never have too many grounds and spray some of that battery wax on all the connections, It will keep all of them from corroding.

 

If I were you I would follow Fmc400's instructions to a tee. Trust me you'll be better off in the end.

 

I haven't done zero troubleshooting, I have been trying to troubleshoot this since august. I've tested everything I could think of up to the ground wires that would affect the battery charge. I checked the fuseable link in the summer with a multimeter and it tested fine then. I don't have a multimeter where I'm at to test it currently and I won't until tomorrow.

The only reason I posted on here was because I haven't been able to figure it out after a while of testing. And before you make another comment about me figuring it out my way instead of following others advice I don't live where the truck is being stored so I only get to work on it a couple days a month that's why it's taking so long and if you notice I've been taking other advice this whole thread. I mentioned just redoing the grounds anyways because I have a ton of wire laying around I can use and I might as well if I have the material.

The reason I mentioned the engine turning over without the key in is because that started happening the same time this issue with the battery not charging started so as far as I know as of now it could have something to do with a bad ground but I won't know until I have time to test it as well.

If I didn't want someone elses advice and if I knew what the problem was I wouldn't have posted, the reason I did was because I don't know what to do from here and I was looking for advice.

 

No need for a pissing contest


I must of missed that when I read through it, But if its turning over by itself its only going to be one of two things...Ignition housing is bad or the solenoid is hooked up backwards...The two small wires just flip around.

 

Sorry about that, had a bit of a pissy mood last night with vehicle issues and other things going on.

Is there a way to test if the small wires are hooked up backwards to be sure? It only happens on occasion, the first time was when I tried to jump it and that was right after I replaced the solenoid so maybe I put them on backwards. The only other times that happens is every now and then when I hook the battery up again.

I will be testing that fuseable link again here in a few minutes now that I have my multimeter back. I also added grounds to add some extra wire and since I didn't have my multimeter to work with. I added one to the front end on one of the bolts that hold on the hood hinges I think, one on a cross section of the cab and one on a cross section of the bed. I had a ton of 10 gauge wire left over from some last projects so I just used that. They are all grounded on the same bolt on the block that the negative battery cable is hooked too and the ones on the bed and cab are grounded to he fram as well. I'll put up some pictures if that makes no sense.

Cab ground


Bed ground


Grounded to the block


I still have yet to hook the alternator back up yet. Do those grounds work out as they are then or should I change them? If they are good I'm hoping they will work. I'm mostly worried about getting the dash lights to work again and the battery issue fixed since today is the last day I get to work on it for a while and I'd like to have this going by winter.