Ketchamized Posted July 5, 2006 Posted July 5, 2006 This isn't for my Allis- this is for my MTD Mastercut with a Briggs engine. For some reason, my engine won't start when the solenoid is connected... This is connected on the positive terminal between the fat starter cable and the battery cable. But, when I bypass the solenoid and hook it up directly, it starts up fast. (Without turning the key) It's my understanding that the solenoid's function is to enable the low voltage key-starter to start the engine without damaging the key switch? Is this true? What would happen if I bypassed the solenoid permanently and installed a push-button start type of switch? Thanks, Erick
BLT Posted July 5, 2006 Posted July 5, 2006 You will burn push button switch quicker then Jack Sprat. The device you are talking about is a starter relay swicth and it allows you to use a low amperage to operate relay and then relay has heavier contacts for starter amperage.
ambler Posted July 5, 2006 Posted July 5, 2006 First pull low voltage wire off and jumper 12 volt line from the battery to the solenoid. Does it turn over? If no you may have a bad solenoid. If yes you may have a bad key switch or wiring from switch to solenoid. check to see if you have 12 volt with key engaged to start from low voltage wire to ground.
Ketchamized Posted July 5, 2006 Author Posted July 5, 2006 BLT, Just as I suspected. Thanks. Much appreciated. :)
Ketchamized Posted July 5, 2006 Author Posted July 5, 2006 Ambler, Thank you for the diagnosis information, will try that now. :)
Ketchamized Posted July 5, 2006 Author Posted July 5, 2006 Ambler, I tried the diagnosing as you suggested with these results: It won't start, no matter what I do with the diagnosis- only way it will start is if it was bypassed. But, it will only start when the key is in the "on" position. When it's on the "off" position, it won't start at all. The switch has 5 wires on the back of it. 2 red, 1 black, 1 yellow and 1 green. Red 1 goes from the positive output terminal (which is also hooked to the headlight switch and the headlights) at the alternator to the starter switch. Red 2 goes to a safety switch, which in turn is connected to a circuit breaker and ultimately to the solenoid. (the small bolt/nut on the solenoid) Black goes from the starter switch to the ammeter, then the circuit breaker. Yellow goes to the magneto Green goes to the ground. I would assume that when it's on the "off" position, it disconnects the negative. When it's on the "on" position, it connects the negative, giving the lights some lighting, and when it's switched on the "start" part, it turns on the starter for the duration of the key being switched that way. So, assuming that is correct, the key switch turns on two different devices(in different positions)- the lights and the starter. Which wires should I short on the rear of the starter to determine if the starter portion of the switch is fried? Is it possible that the starter portion of the switch is burnt out due to a bad solenoid? It's possible that it was bad for a while... I got a new one off ebay, and it doesn't make a difference. I tried using a different switch that has 5 terminals in the back, but it's possible that the configuration is different due to the fact that it's from a craftsman, not a MTD. How easy is it to fry a solenoid? Thanks... :)
Ketchamized Posted July 5, 2006 Author Posted July 5, 2006 Here is the wiring schematic to see the setup: [img]/club2/attach/ketchamized/schematics.jpg[/img]
sandyhillbill Posted July 5, 2006 Posted July 5, 2006 using a jumper wire you can jumper from the hot side of the solenoid to the starter side of the solenoid with the key in the on position to test if the contact disc is burnt. also you can test the solenoid coil by jumping the hot + wire to the small terminal on the solenoid. It should produce an audible click if the coil is operating the solenoid and if the solenoid is good the starter should crank the motor. after looking at your drawing you may have a problem with one of the saftey switches.
ZippoVarga Posted July 5, 2006 Posted July 5, 2006 Eric, frying a solenoid in those box store tractors is pretty easy. If you were cranking for more than 15-20 seconds the heat from the two contacts can and often does melt the plastic/melamine/bakelite case. I would trace all the wires and make sure none were over heated to cause the insulation to burn away causing an undesireable ground. You say you can leave the key in the on position and jump off the starter but when turning the key switch to start you get nothing. This points to the solenoid. See if you can turn the key switch to on and jump between the two terminals on the solenoid. If not, it's fried. They are fairly inexpensive and usually close to universal from TSC. Sears, MTD, Troy Built, Cub Cadet, Yard Man, White are all MTD's these days. Good luck!! Sean
ZippoVarga Posted July 5, 2006 Posted July 5, 2006 Bill, I see we are on the same wave length.....good call ;-)
Ketchamized Posted July 5, 2006 Author Posted July 5, 2006 Bill, Did as you suggested... Here are the results: 1) jumper from the hot side of the solenoid to the starter side of the solenoid with the key in the on position to test if the contact disc is burnt- When I did this, it started up immediately, super fast, just like if I was bypassing the solenoid. 2)also you can test the solenoid coil by jumping the hot + wire to the small terminal on the solenoid. It should produce an audible click if the coil is operating. It has an audible clicking sound, so the coil is operating... 3)Test the solenoid coil by jumping the hot + wire to the small terminal on the solenoid. When I did this, the engine cranked normally as if I were using a key. This felt more normal. So, does this mean that the ignition is bad and the solenoid is working good? Thanks,
Ketchamized Posted July 5, 2006 Author Posted July 5, 2006 Sean, When I turn the key switch on and jump between the two terminals, it starts. The way it's set up is kind of strange, in my opinion. I will attach a computer diagram to show the setup in a better way in a couple minutes...
BLT Posted July 5, 2006 Posted July 5, 2006 Erick, you have two safety switches in your schematic that have to be aligned either to start the engine or make sure you are in seat when you engage mower deck or maybe both.
sandyhillbill Posted July 5, 2006 Posted July 5, 2006 as mentioned above you have two saftey switches and also a circuit breaker that you are by-passing when you jump out the solenoid.
Ketchamized Posted July 5, 2006 Author Posted July 5, 2006 Here is a better diagram of the setup [img]/club2/attach/ketchamized/Setup.jpg[/img]
Ketchamized Posted July 5, 2006 Author Posted July 5, 2006 Bob and Bill, Those two safety switches were originally bypassed. The previous owner mangled up the wires so I had to redo everything in the schematic, by the book. Didn't work, so I took the safety switches out of the equation. Safety switch 1 was set for the blade engage/lower lever. It was already bypassed when I got the tractor. Safety switch 2 was set for the seat, and was already bypassed when I got the tractor. The circuit breaker was hooked up, and I tried it both ways- bypassing it and having them connected, it seemed to make no difference. As for the circuit breaker, what does it do exactly? Prevent overloads? Does it have to be connected in order to make the solenoid work? When I shorted the bottom positive terminal, this would be the lower volt terminal on the soleniod- and bridge it between the hot part, the tractor starts gently, like it was supposed to, instead of a surge. (As opposed to completely bypassing the solenoid) Based on what I was told earlier, it sounds like the solenoid is working. It would seem that the ignition itself might be faulty. Although, some guys here seem to think that it's the solenoid. Hmm... I did purchase a 2nd solenoid, and both of them had the same results. If the solenoid is bad, then I bought a bad one. Any thoughts, anyone? :) I wanted to thank the guys that helped me out on this one, I really appreciate it a lot. :)
ambler Posted July 6, 2006 Posted July 6, 2006 Erick, Did you measure the voltage on the low voltage solenoid wire with key switch engaged to start? If it cranks normally with jumpering it they it may not be gettibg enough voltage to engage from the switch circuit. emory the contacts behind the ignition switch and make sure the safety switch bypasses are still functional
ZippoVarga Posted July 6, 2006 Posted July 6, 2006 Solenoid sounds fine to me too. Still leaning towards a ground somewhere. Since you have a general idea how the system is supposed to work I can only suggest tracing all the wires to make sure you are not grounding or creating an arc somewhere when you try to start the engine. I have had to replace the ammeter wire because vibration wore through the insulation on the wire that's wrapped around the pick up on the ammeter. Could be anything. But as Ambler suggests, it may just be a weak connection as well. Let us know what you find out!! Sean
firefoxz1 Posted July 6, 2006 Posted July 6, 2006 quote:Originally posted by Ketchamized As for the circuit breaker, what does it do exactly? Prevent overloads? Does it have to be connected in order to make the solenoid work? Yes, without the circuit breaker connected the switch will not get any voltage. Easiest way to explain a circuit breaker is it is a fuse that resets itself when it pops/blows. The ignition switch will most likely be marked on the backside what the terminals are for A=accesory B=battery pos G=Ground I=Ignition L=Lights M=Magneto R=?? S=start By looking at the schematic you supplied the voltage for the key switch goes from the hot side of the soleniod to the circuit breaker (black wire) to the ammeter to the switch, from there for starting it goes to a safety switch (red wire) to the soleniod small terminal. Is there voltage at the ammeter? Did someone bypass the "CB" circuit breaker?
Ketchamized Posted July 9, 2006 Author Posted July 9, 2006 Ambler, That might be it... I will be cleaning all the wire connections and making sure everything's connected as well as make sure that the wires aren't bad. It looked good to me at first glance, was kind of overwhelmed with all the mess in the wiring area. Will organize it and take a better look. Thanks for the tip. :) Sean, Thanks for your tips. I'll take a good look at the rest of the system and see if there's a weakness somewhere. The ammeter- the plastic on it is broken and the needle is missing. I'll have to bypass that and see if that was the problem. Firefox1, Thank you for the labelling information. I do have a Craftsman ignition sitting in the garage. I'll have to see if it has the same lettering and see if it'll work with the MTD tractor. Both of them has the same leads in the back, but configuration might be different. The ammeter is broken on the tractor. Would that affect that at all? I was thinking of bypassing it and testing to see if that was the problem after all. The circuit breaker- I tested it with it connected as well as not being connected with the same results. It has to be something else. From what I've read, the more I suspect a weakness somewhere in the wiring itself. The previous owner was my grandfather, and my mother inherited it from him when he passed away in '91. My mother's boyfriend of 13 years fiddled with the wiring and basically ripped everything out and put in his own wiring. It never worked right again. Go figure... Thanks again, guys. Much appreciated. Will keep you all posted on what the problem was. :)
firefoxz1 Posted July 9, 2006 Posted July 9, 2006 quote:Originally posted by Ketchamized The ammeter is broken on the tractor. Would that affect that at all? I was thinking of bypassing it and testing to see if that was the problem after all. All the voltage to and from the battery except to the starter passes through the ammeter so if it has broken connections in it the switch will not get any voltage either. The glass and needle can be broken but still carry voltage through it. This should be an easy check. [img]http://www.simpletractors.com/club2//attach/firefoxz1/switch.jpg[/img] This should be the switch configuration you need.
Ketchamized Posted July 10, 2006 Author Posted July 10, 2006 Firefox, Thanks for the diagram... I looked at the back of the ignition switch, and the letters now make so much sense. I'll have to see if the configuration matches up on the craftsman ignition, or if they were moved around in the back. It'll be good to know for sure if it's the ignition. Sorry about the slow response, my wife got in a bad car accident on Friday and have been in and out of the hospital visiting this recent weekend. Best, Erick
ZippoVarga Posted July 11, 2006 Posted July 11, 2006 Erick, My prayers go to you and your family in this time of need. I hope your wife makes a full recovery and that her injuries are not permanent. Sean
HubbardRA Posted July 11, 2006 Posted July 11, 2006 Erik, I hope your wife makes a speedy recovery. My wife was sitting in a Bagel shop yesterday when a lady lost control of her car and ran thru the front of the store. Missed my wife by about 6 feet. She was very lucky. As far as your tractor, I need to ask one question. Has the ignition been wired with an external coil, instead of the magneto? If so, then there may not be any power going to the coil in the start position of the ignition switch.
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