Generator issues

Firechickenzz

Firechickenzz

Member
Need some help troubleshooting / rebuilding a generator.

On my way back home today from a car show around the last 5 miles of a 35 mile trip the ammeter started bouncing everywhere and then would return to normal. When I got home I opened the hood to hit the battery disconnect and saw the generator about to ignite. The wire coming out of the generator to the cutout was glowing orange and smoking. I think the bearings are fine as I was able to start it up to get it in the garage so its not seized.

20240914_163406.jpg

I guess where do I start? Any good info on testing the cutout and generator?
Is a rebuild worth tackling or is it best to send it out? Or is this a good time to 12v swap?

Thanks
 
Firstly why would you even consider a swap to 12 volt ?? First I would remove the round cut out and look closely at the generator terminal and insulator where it goes through the cut out case. Could have been loose and overheated or shorted to ground which is a common fault. If you dont understand these parts then take it to an auto electrician. New cut out terminal bolts and the special shaped insulators are supplied by THIRD GENERATION AUTO. Please report back your findings before you touch the generator. Regards, Kevin.
 
I might also ask if you have an original Ford quality cut out or a crappy china replacement of inferior quality which has the incorrect terminals for a V8 ,flat ones like on an A model ? Regards, Kevin.
 
If the output wire was glowing red, you had a direct short somewhere. You didn't mention what year the car is, but I can help. I rebuild and restore Ford generators. This is one I recently completed. No need to go to 12v or an alternator.
 

Attachments

  • 20240829_110410_copy_1156x808.jpg
    20240829_110410_copy_1156x808.jpg
    77 KB · Views: 22
  • 20240829_152326_copy_735x667.jpg
    20240829_152326_copy_735x667.jpg
    51.3 KB · Views: 24
Where the black and red wires come out of the generator and go to the cut out they should pass through a rubber grommet insulator, plus both wires are covered with insulation. Third Gen Auto has the rubber insulator and the red wire, he may have the black wire. Both wires have many strands making them flexible, so they are somewhat special.
 
It looks to me that the wire coming from the end of the conduit for the plug wires is placed wrong. It should go to the front of the cut-out, not the back. terry
 
terry said:
It looks to me that the wire coming from the end of the conduit for the plug wires is placed wrong. It should go to the front of the cut-out, not the back. terry
Click to expand...


I think your right. I just pulled the cut out from the generator and now see there are 2 terminals. I didn't remember this because my son pulled the generator off without me when we pulled the engine at the beginning of summer.

Even though the battery and the generator wire were connected to the same terminal I don't think this is the issue for the overheating/short. As I understand it the whole purpose is to disconnect the generator from the battery when not in use to prevent battery discharge. Since I have a full battery disconnect that I flip every time I stop the car it shouldn't have had much impact.

I only have one wire coming from the generator. My brother mentioned it was rebuilt at some point. The cut out is obviously not stock. Maybe some one knows who did it.

I'm assuming at this point something needs to be replaced internally in the generator. Anyone have links to a schematic?


20240915_202901.jpg
20240915_202907.jpg
20240915_202915.jpg
20240915_203933.jpg
20240915_203939.jpg


Update:

I may now know the source of the short. When I pulled the cut out off it sounded like a maraca. When I pulled the cap off I found the 2 insulators rattling around. If the terminal was shorting to the generator housing that would explain the overheating.

20240915_205227.jpg
 
Last edited:
Your round Ford cut out is actually an aftermarket electronic voltage regulator which takes the place of the original cut out. Made by FUN PROJECTS which you can look up the instruction sheet on the web to get a better understanding of it. The regulator will not suffer incorrect connections else it could be damaged. The battery wire goes on the front side of the reg and the generator main brush output wire goes on the backside of the regulator. Regards, Kevin.
 
koates said:
Your round Ford cut out is actually an aftermarket electronic voltage regulator which takes the place of the original cut out. Made by FUN PROJECTS which you can look up the instruction sheet on the web to get a better understanding of it. The regulator will not suffer incorrect connections else it could be damaged. The battery wire goes on the front side of the reg and the generator main brush output wire goes on the backside of the regulator. Regards, Kevin.
Click to expand...

I found this other post. https://fordbarn.com/forum/showpost.php?p=1915051&postcount=4 "After looking at the design, it's not a very good one. I suspect that high speed operation for long periods (road trips) will overcharge the battery."

This is probably what did me in. I was on a 35 mile drive all high speed. I'll have to pop the battery cover and see what the battery condition is.
 
The Ford cut out cover has square holes for the electrical connections. The special washers that fit on the outside of the metal cover fit onto the square holes and are held in place by the special hex head screws for the attachment of the wires. The special washers and screws are sold by Third Gen Auto in Tenn.

It is possible the round washers you found could also fit on the outside of the cut out. Check that out and make sure to to use an ohmmeter to make sure there is no continuity between either of the cut out terminals to ground before connecting the battery. The generator red wire goes to the "A" terminal and the generator black wire goes to the cut out mounding screw. Appears the rebuilder connected it inside the generator body.
 
Firechickenzz said:
I found this other post. https://fordbarn.com/forum/showpost.php?p=1915051&postcount=4 "After looking at the design, it's not a very good one. I suspect that high speed operation for long periods (road trips) will overcharge the battery."

This is probably what did me in. I was on a 35 mile drive all high speed. I'll have to pop the battery cover and see what the battery condition is.
Click to expand...

I dont agree with your opinion on this one. I have fitted several of these regs to early ford V8s including my original 34 sedan which has been fitted for over ten years. They do however work differently to a field control regulator, The fact that your reg has maybe been connected wrong with the battery supply wire on the generator terminal would not help it at all. As i said, read the instruction sheet that comes with the reg and stick to those instructions including the third brush setting. Dont knock a component that you know little about. Regards, Kevin.
 
koates said:
I dont agree with your opinion on this one. I have fitted several of these regs to early ford V8s including my original 34 sedan which has been fitted for over ten years. They do however work differently to a field control regulator, The fact that your reg has maybe been connected wrong with the battery supply wire on the generator terminal would not help it at all. As i said, read the instruction sheet that comes with the reg and stick to those instructions including the third brush setting. Dont knock a component that you know little about. Regards, Kevin.
Click to expand...

Unfortunately I didn't get the instructions when I took possession of the car.

At this point I think it may all be moot. I took a closer look and the regulator looks to be damaged.

20240916_105518.jpg

Any suggestions on a replacement?
 
You must log in or register to reply here.
Back
Top