tgranthamfd 28 #1 Posted April 2, 2016 Ok, Just picked up a, Idk, a 83 or 84 GT 1642 Work Horse, Has the ole big Briggs twin in it. The guy says he was mowing and it just died. That was last season. battery was dead, charged it, fuel was empty, put some in it, seat switch was disconnected, put a jumper in between. I assume the clutch and engage switches are hooked up. Charger hooked up, butt in seat, disengaged, clutch pushed in, turn key, and nothing, notta, zero, zilch. Hooked a jumper cable to the starter post, and stuck to the battery, and starter did not engage. Got a little smoke from around the ignition switch area so unhooked the cables. Had to get home, so where do you guys and gals think is a good place to start looking for the issue. I'm thinking there is a grounded wire, down in that area somewhere, it's a very tight turn coming up through there before it plugs in to the ignition. The poor old horse did set outside under a pine tree since last summer! P.O. just didn't have the time or means to mess with it, plus I got it for what I sold him the deck for, a couple of years ago, $100! What do ya think? Share this post Link to post Share on other sites
rmaynard 14,932 #2 Posted April 2, 2016 (edited) That model has a magneto ignition. If you are in the seat, you are opening the grounding circuit to the magneto, allowing it to run. Putting a jumper on the seat switch wires is the same as getting out of the seat. It shuts the engine off. Click this link for your wiring diagram. Edited April 2, 2016 by rmaynard 3 Share this post Link to post Share on other sites
953 nut 52,006 #3 Posted April 2, 2016 6 hours ago, tgranthamfd said: Hooked a jumper cable to the starter post, and stuck to the battery, and starter did not engage. Got a little smoke from around the ignition switch area so unhooked the cables. Disconnect the wire to the magneto and the wire to the starter and try jumping it as before; if the starter is good it will turn over and if the mag. is good it may start. If it starts you will be able to shut it off by plugging the wire to the mag. back in. Once you know what works and what doesn't, you can use the diagram Bob gave you to isolate the problem; probably a simple disconnected or shorted wire. $100, you done good. Share this post Link to post Share on other sites
tgranthamfd 28 #4 Posted April 3, 2016 Thanks guys, I will give it another look today. So the seat jumper is ok, if I'm not sitting in it? Share this post Link to post Share on other sites
tgranthamfd 28 #5 Posted April 3, 2016 Never mind, I just reread it, I need to take the seat jumper wire out completely? It's just that it is still up in the back of the truck, kinda hard to climb in and out of the seat. but it would not do anything before the jumper, either. I think I will pull the battery and get a visual on all of the wires, that I can, I think that is where the problem may be. Share this post Link to post Share on other sites
tgranthamfd 28 #6 Posted April 4, 2016 Well I think I have gotten it narrowed down to the ignition switch. Bypassed it and used a jumper start button, couldn't get her to start, wouldn't pull fuel up to the carb. found severely cracked fuel lines between the filter and carb. Replaced filter and some fuel line, primed, and got it to start and run, with the button. So I figured it had to be the solenoid, so I replaced it. Still the same thing, no start with the switch, but would start with the button. I do know the switch will kill the engine, and will let it run, just not start. I realized, after the fact, that I could have checked the solenoid by hooking the starter button up, in a different spot!. I have another ignition switch somewhere, to test and see if it will work, just have to find it. Are all wheel horse ignition switches the 6 connector? At least I did find out my $100 Work Horse does run and sounds good, and the solenoid was not the problem! got a good look at most of the wiring while changing out the solenoid, as well!, and all looked ok, 1 Share this post Link to post Share on other sites
squonk 39,032 #7 Posted April 4, 2016 Be sure to use the right switch. Battery ign and mag ign switches look the same but they are different. Make sure the one you grab has a "M" on it! Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,530 #8 Posted April 4, 2016 You need the 103991 ignition switch. There are 2 switches that are identical except for one terminal. You need the one with the ignition terminal identified with the letter "M" for magneto ignition. If you used the one with the ignition terminal identified by the letter "I" (eye) for battery ignition the coil will burn up. Garry 1 Share this post Link to post Share on other sites
tgranthamfd 28 #9 Posted April 4, 2016 Yes sir's, Toro #103991 is the part number I am looking for. I have found some conflicting information, so thought I would just try to find a new one. I read an old post about testing the switch, may try that first. How do you check the PTO, and clutch switches? Seat switch is already undone! 5 hours ago, gwest_ca said: You need the 103991 ignition switch. There are 2 switches that are identical except for one terminal. You need the one with the ignition terminal identified with the letter "M" for magneto ignition. If you used the one with the ignition terminal identified by the letter "I" (eye) for battery ignition the coil will burn up. Garry 5 hours ago, squonk said: Be sure to use the right switch. Battery ign and mag ign switches look the same but they are different. Make sure the one you grab has a "M" on it! Is the "M" and the "I" the only difference, will the other 5 terminals have the proper letter / orientation? Share this post Link to post Share on other sites
tgranthamfd 28 #10 Posted April 4, 2016 If I read the old post correctly, it said to put meter on the lowest ohm setting, put black lead to the negative battery, and touch the red lead to the part where the key goes, and I should read an open. Does this sound correct? For testing the ignition switch, I should say! Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,530 #11 Posted April 4, 2016 When you use an ohmeter the meter uses batteries in the meter. Do not allow the test leads to contact voltage from the tractor so when testing the negative battery to the switch disconnect the negative battery cable from the battery and isolate it so it does not accidently contact the battery post. Then you can safely connect to the cable and switch. When the negative battery cable is disconnected the positive cable is also isolated from the tractor because the battery is not in the circuit. The pto switch is actually two switches in one. N.O. is normally open. N.C. is normally closed N=normal switch status when not activated by button or lever. The starter circuit 1/2 of the switch is closed with the pto OFF (N.O. Contacts closed when pto disengaged) Pto OFF allows you to activate the starter if the transmission clutch switch is also closed. The ignition circuit 1/2 of the switch is open with the pto ON (N.C. Contacts closed with pto engaged) With the pto ON the ignition wire is connected to the seat switch which grounds the ignition if operator leaves the seat. Clear as mud? Garry Share this post Link to post Share on other sites
tgranthamfd 28 #12 Posted April 4, 2016 1 hour ago, gwest_ca said: When you use an ohmeter the meter uses batteries in the meter. Do not allow the test leads to contact voltage from the tractor so when testing the negative battery to the switch disconnect the negative battery cable from the battery and isolate it so it does not accidently contact the battery post. Then you can safely connect to the cable and switch. When the negative battery cable is disconnected the positive cable is also isolated from the tractor because the battery is not in the circuit. The pto switch is actually two switches in one. N.O. is normally open. N.C. is normally closed N=normal switch status when not activated by button or lever. The starter circuit 1/2 of the switch is closed with the pto OFF (N.O. Contacts closed when pto disengaged) Pto OFF allows you to activate the starter if the transmission clutch switch is also closed. The ignition circuit 1/2 of the switch is open with the pto ON (N.C. Contacts closed with pto engaged) With the pto ON the ignition wire is connected to the seat switch which grounds the ignition if operator leaves the seat. Clear as mud? Garry So disconnect the negative cable, and check continuity between the cable end and the switch front, and it should read no continuity? Is the mud getting clearer? Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,530 #13 Posted April 4, 2016 If you are checking to the front of the switch which is part of the switch body you should have continuity to the negative battery cable if the switch is mounted to the chassis. If you put the ignition switch in the RUN and also the START positions you should NOT have continuity between the M terminal and the negative cable in either key position. In the OFF position you should have continuity between the M terminal and the negative cable. Don't know what old post you are referring to. Garry Share this post Link to post Share on other sites
tgranthamfd 28 #14 Posted April 5, 2016 10 hours ago, gwest_ca said: If you are checking to the front of the switch which is part of the switch body you should have continuity to the negative battery cable if the switch is mounted to the chassis. If you put the ignition switch in the RUN and also the START positions you should NOT have continuity between the M terminal and the negative cable in either key position. In the OFF position you should have continuity between the M terminal and the negative cable. Don't know what old post you are referring to. Garry Got ya. I went back to look at the old post and couldn't find it again! I been searching so much, the last few days, I don't know what I read and what I didn't! Share this post Link to post Share on other sites
tgranthamfd 28 #15 Posted April 5, 2016 Ok, negative led off and isolated, switch mounted, continuity to the front of switch where key goes in, in stop, run, and start. Checked from neg. cable end. Does this mean the ignition switch is, in fact, bad? At least I think I read your instruction right. 21 hours ago, gwest_ca said: If you are checking to the front of the switch which is part of the switch body you should have continuity to the negative battery cable if the switch is mounted to the chassis. If you put the ignition switch in the RUN and also the START positions you should NOT have continuity between the M terminal and the negative cable in either key position. In the OFF position you should have continuity between the M terminal and the negative cable. Don't know what old post you are referring to. Garry 1 Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,530 #16 Posted April 5, 2016 That just tells you the switch body is grounded so when the key it turned OFF the M terminal should kill the ignition if the switch is working correctly. Now If you put the ignition switch in the RUN and also the START positions you should NOT have continuity between the M terminal and the negative cable in either key position. With the key in the OFF position you should have continuity between the M terminal and the negative cable. Garry 1 Share this post Link to post Share on other sites
tgranthamfd 28 #17 Posted April 5, 2016 (edited) 1 hour ago, gwest_ca said: That just tells you the switch body is grounded so when the key it turned OFF the M terminal should kill the ignition if the switch is working correctly. Now If you put the ignition switch in the RUN and also the START positions you should NOT have continuity between the M terminal and the negative cable in either key position. With the key in the OFF position you should have continuity between the M terminal and the negative cable. Garry Which one is the "M" terminal, the #3 that is off by itself? the other 5 are within 1 connector. If so, they all still carried continuity with the negative cable, while unhooked? I did print off the wiring diagram, that you guys put up, but it is out in the truck, I think. When I was saying the front of the switch, I actually meant where the key goes in, not the front of the case. Edited April 5, 2016 by tgranthamfd Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,530 #18 Posted April 5, 2016 Here is a view of the back of the switch with the terminals identified. https://www.bantasaw.com/catalog/viewproduct.asp?i=&p=3905 Garry Share this post Link to post Share on other sites
tgranthamfd 28 #19 Posted April 6, 2016 13 hours ago, gwest_ca said: Here is a view of the back of the switch with the terminals identified. https://www.bantasaw.com/catalog/viewproduct.asp?i=&p=3905 Garry Ok, so the one that is not in the factory plug appears to be the "G", which the diagram at the top says is not used. The "M" wire is one that I can not get to unless I pull the panel or the switch, to check it. I need to go out and do some more checking, if I pull the panel, I loose ground. Maybe I can set it somewhere, as not to loose ground so I can ohm it? Share this post Link to post Share on other sites
pfrederi 17,173 #20 Posted April 6, 2016 You can run a wire from the "G" terminal; to a ground somewhere on the tractor while you have the switch removed for testing. The G terminal is provided so you can run a wire to a ground point if your switch can't be grounded by the mounting point. Some tractors have plastick dashboard so the Switch case isn't grounded. They need a ground terminal and separate wire to a good ground. Share this post Link to post Share on other sites
tgranthamfd 28 #21 Posted April 6, 2016 4 hours ago, pfrederi said: You can run a wire from the "G" terminal; to a ground somewhere on the tractor while you have the switch removed for testing. The G terminal is provided so you can run a wire to a ground point if your switch can't be grounded by the mounting point. Some tractors have plastick dashboard so the Switch case isn't grounded. They need a ground terminal and separate wire to a good ground. I've got a wire hooked to it, going somewhere. Guess I need to track it down! Share this post Link to post Share on other sites
tgranthamfd 28 #22 Posted April 8, 2016 Found the other information I had talked about earlier, in a keyswitch wiring post, from a couple years ago. Here it is. They was talking about testing the ignition switch. Set your multimeter on ohms (lowest range if the meter isn't auto ranging). Connect the black probe to battery NEGATIVE. Touch the red probe to the exposed metal of the ignition switch body (where ignition key is inserted). The meter should show a direct short. If not, touch the red probe to a non-painted area on the metal hood stand that holds the ignition switch There should be continuity of the battery negative to the hood stand and continuity of the hood stand with the metal body of the ignition switch. Share this post Link to post Share on other sites
tgranthamfd 28 #23 Posted April 18, 2016 Well, switch didn't fix it either, guess it has to be the PTO switches, or the clutch interlock. So how do you test those? Still the same with a new ignition switch. Will start with a remote start switch, but key has to be on, and key does kill the engine. Seat switch has been removed and the seat wires are not hooked to anything, I even grounded the black seat wire just to see if it helped (black wire), and it did not. Starts every time, with the remote start, through the solenoid, so the battery is charging, which means the magneto should be good? I have held in the clutch, turned to start, and wiggled the PTO lever all around, nothing clicked or did anything. Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,530 #24 Posted April 18, 2016 The wire going from the ignition switch to the pto switch for the starter circuit should be tan in color. There are 2 pto switches side by side. The switch with the same tan wire is for the starter. With the pto OFF the tan wire should feed 12 volts to the purple wire on the same switch. See if you get that when the ignition key is in the START position. If you do not get 12 volts on the purple wire the pto switch is not closing. If you do get 12 volts on the purple that wire goes on to the transmission clutch switch. With the clutch pedal down that switch should power the starter solenoid like your remote starter switch does. I'm saying 12 volts. If it is easier to use a test light use it. The problem could be the switch, the wire connections or perhaps the switch button or lever is not getting pushed as required to close the switch. Let us know what you find. This 1983 operator manual has a wiring diagram showing the wire colors Garry Share this post Link to post Share on other sites
tgranthamfd 28 #25 Posted April 19, 2016 Thanks for the link to the manual, mine must be a late production model, some of the wiring are mostly black with colored stripes. I will have to study it some. I know both of the clutch interlock wires are black with a light blue stripe. Share this post Link to post Share on other sites