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well I guess you can call it that I think I have found that it is the circuit that controls the idle control solenoid, "anti dieseling solenoid"
It seems that there is a relay on the fender that is called the starter interrupt relay I really got to look over the wiring diagrams to see how this all works but when it is powered on "switch in start I have 12 volt on the solenoid on the carb then when the engine cranks "If it is acting a fool" I lose the 12 volts. when it is running good I have 12 volts I think the other relay may be where it gets it, got to look over the wiring diagram from this web sight. while I was working on it today I put a wire from the battery to the anti dieseling solenoid and the truck ran great so I decided to put a toggle switch and spice into the wire near the carb only problem is when you turn the toggle switch on and push in the clutch the truck cranks over the motor. If the switch is off or on it will crank itself if the switch is on and when it starts to run the starter kicks out as if I had cranked it myself. It must be that the starter interrupt relay is controlled by the motor speed sensor this may have been to keep people from grinding the starter when the motor was running or something like I said this is just speculation I will look over the diagrams with a magnifying glass to see if I can figure this out. I have some extra relays my uncle brought by yesterday If I can't find a one that works all the time I will see if I can take one apart and file the contacts on one. does this ring a bell with any one who has had this problem or know more about how all this wiring works. Thanks for any help and I hope this will help some of you too.

Sorry. The more I read about the Hitachi carb problems and the psychotic problems I have with mine, I think a weber is in store for my truck.

Is your choke getting power? Those two items are inner tied. It is also tied into the fuel pump relay.

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Certified pilots, looking down on people since 1903.

I did notice the other day that when it was running so bad that there was no voltage in run to the solenoid but I didn't check the choke heater connection "unplugged the carb connection an made it run with a jumper from the battery to the solenoid while I checked voltage with a meter after a couple of times re cranking the engine the voltage was there again so I quickly hooked the carb back to the wiring harness and it ran just fine so I know I have times that I loose that voltage I also know from the drawings that it receives voltage form one source while it cranks then swaps to another when it is running. Really need a clear print of the wiring to have a chance at finding it."
I cranked it today and drove it around it runs like new again when I turn the switch on that I added it made no difference how it ran today, not that I expected to just thought I would try it. I want to test this but I cant get it to start acting up for some reason. I also noticed that the switch did not crank the motor over today when I switched it on and the engine was not running, so that says something about the problem I have tried to look over the wiring diagrams from this sight. I took a yellow marker and traced out part of the circuit it is just so hard to make out much on it but from what I have read the engine speed sensor was only on California models so I'm really confused as to what made the starter kick out after the engine started when it was acting so crazy yesterday. does anyone have a better place to get the wiring diagrams on line or any idea about this wiring. Thanks.
Wayne in SC

If you haven't done this yet, I'd recommend it.

viewtopic.php?f=7&t=17082&p=127920&hilit=lemon+juice#p127920

Also check your grounds. There are two that run out each side of the harness and mount on the inner fenders. These often break off. They look sort of like a shoelace (woven ground strap) and are about the same dimension. They have an eyelet on them that tends to still be mounted on the firewall, but the ground strap is often hanging or missing.

Intermittent stuff on these trucks seems to mostly be due to poor connections. If the problem is aggravated when you drive it, that's a pretty good indicator that either heat (usually seen in the voltage regulator) or vibration are causing your problems.

Not sure what year your truck is, but the main page of this site has all the .pdf files for the harness. Scroll down to Factory Drawings and Parts Listsings http://www.luvtruck.com/Information.htm

Good luck..

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"If we did the things we are capable of, we would astound ourselves" - Thomas Edison

I'll look at those ground straps tomorrow thanks for the last two days it has ran great I drove it all over the neighbor hood but since I put that wire to it and through a switch it has been fine. when I ran it across the fire wall I rolled the harness out of the metal keepers and used ty-raps to hold the wire against it then rolled the metal keepers back tight around the harness this may be what has cured it for now holding a wire that is broke inside together better then again it may go to pot tomorrow. I'm going to keep it till Monday to see what it does then I will give it back to him to see what happens. I got some pix of it today hope to post them tomorrow. I downloaded the pdf on the wiring but it was hard to read so I saved it to the clip board put it in paint and changed the contrast to lighten it up. this helped allot.

Ok the truck is still running fine today but I redone the ground straps on both sides this 1980 had regular wires not the braided kind. I went ahead and put a #12 ground wire to the body straight off the battery along with the ground straps on that side. sure can't hurt I should have thought of that myself . Thanks allot for that great suggestion.

Well after several days of running really well I took it back to my uncle We hope it keeps running well and maybe next spring we will lay down a coat of paint on it. I got some Ideas from the truck photos on this site. you guys have some sharp trucks. thanks for the help again.