Vista wiring problems

I am posting a wiring diagram for a Vista Diesel. I've got issues as this tractor was sitting quite a while until I overhauled it and it runs great now but no gauges work at all. I had to put on a mechanical oil pressure gauge to run it out but I have no temp gauge, trans pressure light or even the amp gauge won't move. I found and cleaned the ground strap that goes from the metal plate under all gauges to the frame but that didn't help. I don't think the fuel gauge worked before. I do have power to the key and can key start it now. I found a melted pink wire in the harness going to the voltage regulator so replaced that and now the regulator clicks when key is turned on. I have power to both sides of the ammeter, is that correct or is it just passing through? This diagram shows from live starter terminal to positive side of ammeter, I have live to both. It was that way but maybe I should disconnect the negative terminal and connect to the B on alternator like it shows or doesn't that matter? Then the diagram shows the regulator as (B)& F terminals but my regulator has 1 2 3 4 numbered posts so I don't know where to hook things up to?? Any pointers would be appreciated.

The ammeter is a pass through device and should be always hot on both sides. One side should receive power from charge stud on alternator, other side should go to hot battery side of starter solenoid. Power to switches should come from alternator side of ammeter. Leave the ammeter wires alone.

As for gauges I believe the #24 power pack feeds power to the gauges. Check that you are getting power into it.

Diagram is small and very hard to read. I saved as a picture but when trying to enlarge it, it breaks up. This is normal for a lot of posted diagrams.

Can you tell what brand of alternator you have?

Thanks for the help. It looks like a Delco type but I will go check. It has the one big nut with the larger wire on that and then a smaller round end one plugged in to that and I have that one heading nowhere right now. Actually I don't even know if it will charge because it has the original yellow paint on it yet and I can't remember if it charged when we used to use that tractor in the fields and the wiring one time had a short that melted a couple wires together. Maybe I just need to go get a new alternator and a new regulator too to try to get it all back right. When you say that #24 power pack, is that the thing in the center of the frame under the cover? I thought that was something that was used to make those glow gauges light up, I'll have to go check that for power now too if they are to power up the gauges. Thanks again.

'Be careful the "electroluminscent" gauges on a '60 Chrysler 300F worked on several hundred volts. It would let you know if you got ahold of it. I was quite familiar with the jolt, similar to spark plugs. I haven't worked on the dash of my Vista but it may be similar. Most electrical gauges have some sort of 5 volt power supply to operate the functions of the gauges, may be internal to one of the gauges.
Bryce

Yes, I did put 12 volt power to the one side of that power pack with a jumper wire and I could then hear a slight hum coming from it, when I checked the out wire that would be going to the gauges I was amazed to see my meter light up near 120 volts. If I remember from some earlier posts on this site I believe that pack was there to make the gauges glow in the dark, some sort of illuminator but I may be mistaken, maybe it is required to run the gauge itself. I stopped fooling around with it for now as I couldn't get the power to flow to it through the harness anyway. I did manage to get the electric oil pressure gauge and fuel gauge to operate now without the power pack powered but nothing from the temp gauge yet. Could it just be a bad gauge or sender? The wire is connected but I'm not sure if there is a way to check for current coming to or from the sender? Thanks for any help.

To check the gauges, and many other types of gauges ground the wire that goes to the sending unit to the frame of the tractor. If the gauge pegs to full you have a sender problem. The temp sender is readily available.

Also the power pack is for the green back light of the gauges and has nothing to do with the actual operation of them. If I recall the green light is 220 volts AC current. I have quite the experience with the wiring on these tractors, the only fail I have had is my amp gauge on my 302 flickers (doesn't show a steady charge) an I have no idea why. I wish someone would make a quality replacement for these gauges and senders.

Thanks for those last two replies Joe Pro, I never was sure of how to check out the sending units before. My fuel gauge wants to go to the full mark as soon as the key goes on and the tank was near empty. Does that indicate a bad sender in the tank or maybe a shorted wire, I haven't followed the wires yet as they are mixed up with the light wires under the platform it appears. My amp gauge still doesn't move and I am sure my alternator doesn't charge. Is there a way to check the output to see if it's charging besides looking at the gauge which may also be bad. That gauge doesn't even flicker when you hit the starter and I'm sure they should go towards the discharge side at that point or am I wrong. Thanks, you have all been very helpful.

The best way to determine if an alternator is working is to measure the voltage across the battery. With the tractor not running it will show 12.6v or less depending on the charge in the battery. Start the tractor and if the voltage increases the alternator is working. If it shows above 14.5-15 volts, it is working too good and the regulator needs adjusting or replacing.
Bryce