VAC about has me pulling my hair out

old · May 29, 2018

So I install a new starter button. Picked up 2 different ones which turned out to be good since one was bad right out of the box. Got it fired up and noticed the alternator was not working. Found belt tensioner was loss due to a broken bolt. Fixed that and got the belt tight. Still no charge. Tried a few things and finally got to work. The 2 wire plug the #1 wire was not making good contact so which I pull the plug out and put it back in it started to charge. But now it will not shut down at the switch. Tried a couple of things that in the past have worked just fine. Tried the ballast resister thing to make it shut down and that did not work. Put the diode back in and that still did not work. So I now have to shut of down by shutting off the gas. Oh well at least it is now ready to rake hay once it is dry enough

Bret4207 · May 29, 2018

You pulled the wire off the ballast resistor between the switch and coil and it still ran?

mEl · May 29, 2018

(quoted from post at 16:42:04 05/29/18) So I install a new starter button. Picked up 2 different ones which turned out to be good since one was bad right out of the box. Got it fired up and noticed the alternator was not working. Found belt tensioner was loss due to a broken bolt. Fixed that and got the belt tight. Still no charge. Tried a few things and finally got to work. The 2 wire plug the #1 wire was not making good contact so which I pull the plug out and put it back in it started to charge. But now it will not shut down at the switch. Tried a couple of things that in the past have worked just fine. Tried the ballast resister thing to make it shut down and that did not work. Put the diode back in and that still did not work. So I now have to shut of down by shutting off the gas. Oh well at least it is now ready to rake hay once it is dry enough

If it is a Delco S10 alternator and backfeeds and keeps it running it is still backfeeding shut off and will draw the battery dead, a diode will fix itbut you must have a failed one or have it reversed.

old · May 29, 2018

I have the diode so the line faces the alternator as per what it should be plus a ballast resister in line. Either one alone should keep it from back feeding but they are not for some odd reason. I will have to look it over a bit more in the future and this is the first-time I have even had a problem like this. My Oliver S88 uses a ballast resister to keep form back feeding and most of my other ones use the diode and I have NEVER had a diode go bad

old · May 29, 2018

Ballast resister in in line with the #1 wire on the alternator as to stop back feed which is one of a number of ways to do that but it is not working on this one. Coil is a true 12 volt coil no resister needed. Plus I have a diode in line with the ballast resister going to the #1 wire of the Delco 10si either one should be enough to stop the back feed but they are not doing so for some odd reason

nick831 · May 29, 2018

How about run a new wire from the switch to the cool outside of the charge circuit. I take it you have the switch that allows you to change the charge from regulated to full? I know an isolated wire from the switch will kill it, lose power to the coil and it must stop. Just my idea, I am sure there are many more out there with more knowledge than myself on the VAC wiring. Hope you get it fixed shortly☺

old · May 30, 2018

This is a 12 volt conversion using a Delco 10si 3 wire alternator. It is wired like many of the others I have done and this one does not work like it does on others for some reason. Only thing I can maybe think of is that there is a wire out of place some how

nick831 · May 30, 2018

It is odd how it would work before and now it is giving you fits. I don't believe I heard you say you did any rewiring on the tractor, can you back trace the source of power to the coil, this would surely tell you what is back feeding the circuit. I could see a bad alternator doing this especially if the excitement wire comes off the ignition switch as i am sure it does, not alot of accessories to tie into on a tractor.

old · May 30, 2018

On this one I go from the ignition wire on the coil to a diode then to the #1 terminal on the 2 wire plug. The diode should stop alternator back feed but it isn't. I then tried a ballast resister like I have on my Oliver S88 and that too did not work. I have hay to rake today so will rake the hay then when done and ready to shut it off I'll remove the wire from the excite side of the alternator and see if that shuts it down. If that works I know it is a bad resister and or diode if it doesn't then it makes me think something odd is going on with the switch

nick831 · May 30, 2018

You know an easy fix would be to find a spot on the ignition switch that you know is not backfeeding and run the wire from that. Could a terminal maybe have moved and jumped across your switch? Maybe the switch is just bad and wont stop the flow of voltage or partially stop. An easy test on the alternator would be to disconnect the wiring from it, the plug and the large charge wire and see if the tractor shuts off normally.

old · May 30, 2018

Ignition switch is a simple 2 wire on/off switch. I raked the hay then shut the switch off and it kept running. It is wired right now with both the diode and ballast resister in line so that should double the chance of it shutting down. So since it did not shut down I pulled the wire off the ballast resister, spade type hook up it shut down so guess both the diode and ballast resister are bad

nick831 · May 30, 2018

OK two terminal switch. 12 volts coming in on one side and 12 volts switched out the other side going to the coil and excitement wire for the alternator, is this correct? If so you can disconnect the excitement wire from the alternator and this should stop the problem proving the alternator has a problem. I agree the diode should fix it as its a one way valve. Easy to check the diode with a multimeter on ohms, voltage should pass one direction, when you flip the leads it should not.

old · May 30, 2018

My VOM has a diode check setting. I just have not gotten to that point as of yet and will probably get around to it in a few days. Now that I know the fast way to shut if off it is one of those thing that is a round to it type of thing. If I still had a diode laying around I would just swap it to see if that was the problem but since Radio shack shut down I have not been able to get the diode I once kept on hand

nick831 · May 30, 2018

Got it. Well good luck, sounds like you have it nailed down pretty good for now. Nick

old · May 30, 2018

Yes but it was a real pain when 2 things that have always worked did not for some reason. If I had known Radio shack was going to close down I would have stocked up on those diodes

nick831 · May 30, 2018

Another easy way to do it without a diode is a normally closed under pressure, oil pressure switch plumbed into the oil galley port.

ArleninOr · May 30, 2018

Rich, post the number of your diode and will see if I have any. Also still have a Radio Shack close to me.

old · May 30, 2018

If I remember right the Radio shake number for it was 276-1661. It was a 6 amp diode with a peak voltage of 400 or so volts. The diode it self has no number on it and it has been 3 plus years since I could get them locally

old · May 30, 2018

It would take a pretty low pressure switch to do that. Bet this VAC doesn't have 20 PSI oil pressure but hard to be sure since it came with an oil pressure gauge that reads 0 to 80 PSI

kevinthefixer · May 30, 2018

Here's one (actually five) on Amazon with the specs you posted. I would think you could get away with less, probably 100V and 3A, but certainly cheap enough either way.
https://www.amazon.com/NTE-Electron...527731398&sr=8-15&keywords=diode+400v

old · May 31, 2018

Being on dial up doing any thing like that would take longer then it is worth. As for the diode I used I used it because it was way over kill and since thing one is bad that says either it was bad from the get go or it burned out for some odd reason

kevinthefixer · May 31, 2018

Dial-up sucks, no doubt about that.

old · May 31, 2018

Well where I live it is all I can get with out paying around $100 per month and that would be satellite which I have heard is not all that good either

kevinthefixer · May 31, 2018

Satellite isn't that great, but it's miles ahead of dial-up. I'm lucky enough to get land-based radio internet for about $65, it's somewhere between satellite and fiber optic cable, and I do enough computer work to justify that. Makes Mama happier too, and as you probably know, if Mama ain't happy, ain't nobody happy!

old · Jun 1, 2018

Wife does not use this computer at all. If she wants to get on line she goes to the liberty

VAC about has me pulling my hair out

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Member

Well-known Member

Member

Well-known Member

Member

Well-known Member

Member

Well-known Member

Member

Well-known Member

Member

Well-known Member

Well-known Member

Well-known Member

Member

Well-known Member

Member

Well-known Member

Member

Well-known Member

Similar threads