thermo-start issues

[thepumpguysc]

bad switch.?? not turning it correctly.??

 

[bazman82]

bad switch.?? not turning it correctly.??

There is only one way to turn the key for that light to come on. It could be a bad switch but wouldnt power not be supplies to the thermostart if that was the case? There is an electro valve that controls the fuel to the thermostart that has 1 wire hooked to it. I have a picture of it on page of this thread. Its number 62. It has power as well. Would this affect the thermostart heating up if it was bad?

 

[thepumpguysc]

If I remember correctly, u push IN on the key & turn it to the LEFT to energize the thermo-start..

 

[bazman82]

If I remember correctly, u push IN on the key & turn it to the LEFT to energize the thermo-start..

Is that for farmtracs? I believe the method to energize a thermostart varies between tractors. I'll give it a shot when I get home but I know I have tried turning it left but never pushed it in and tried it.

 

[Texasmark]

Seems you identified a wiring problem. My first guess would be to get a helper and a voltmeter. Have the helper energize the TS function and you check the voltage between the TS input spade lug (not the interconnecting wiring lug on the TS spade) and the case OF THE TS. You should have 10V or more.

IF not, check the same lug to battery -. 10v min. Ok move on, nada, clean up the threads of the intake manifold....not making a good ground.

Next is the wiring lug attached to the TS input spade. High temps encountered over the years could cause corrosion of that terminal and reduced continuity whereby the voltage is dropped across the wire to terminal crimp which will cause it to get hot....easy way to detect.....if oxidized or hot, clip the wire and crimp on a new terminal to nice and shiny wire.

Next would be the same terminal type problem at the ignition switch or a high current relay that the ignition switch operates...get a wiring diagram or trace the wiring.

Next would be the switch terminal interface and if not that, it's internal contacts.

 

[bazman82]

Seems you identified a wiring problem. My first guess would be to get a helper and a voltmeter. Have the helper energize the TS function and you check the voltage between the TS input spade lug (not the interconnecting wiring lug on the TS spade) and the case OF THE TS. You should have 10V or more.

IF not, check the same lug to battery -. 10v min. Ok move on, nada, clean up the threads of the intake manifold....not making a good ground.

Next is the wiring lug attached to the TS input spade. High temps encountered over the years could cause corrosion of that terminal and reduced continuity whereby the voltage is dropped across the wire to terminal crimp which will cause it to get hot....easy way to detect.....if oxidized or hot, clip the wire and crimp on a new terminal to nice and shiny wire.

Next would be the same terminal type problem at the ignition switch or a high current relay that the ignition switch operates...get a wiring diagram or trace the wiring.

Next would be the switch terminal interface and if not that, it's internal contacts.

This is where I lack in experience. I am assuming TS = trigger switch. Trouble shooting electronics is definitely not my strong suit and I mostly end up replacing things till it works...while this helps me gain the experience of working with that stuff, it becomes expensive after awhile.. I think at some point this week I'll fire up the tractor and park it in the shop to take the dash off and try testing the voltage. I do have a wire diagram as I do have the workshop manual but the wire diagram is all greek to me.

 

[Texasmark]

This is where I lack in experience. I am assuming TS = trigger switch. Trouble shooting electronics is definitely not my strong suit and I mostly end up replacing things till it works...while this helps me gain the experience of working with that stuff, it becomes expensive after awhile.. I think at some point this week I'll fire up the tractor and park it in the shop to take the dash off and try testing the voltage. I do have a wire diagram as I do have the workshop manual but the wire diagram is all greek to me.

TS...Thermo Start device.

Think about a water pipe. To get a given flow of water it takes so much head pressure and a certain sized pipe of a certain internal resistance. If you reduce the pressure or the size of the pipe, or the interior of the pipe becomes rough, or in comparing a rough interior to a smooth one, you will have reduced flow.

In electricity, the load (the Thermostart device) requires a certain flow of electrical current to heat to the required temperature to make it work. Bad connections, or corroded wire, or a low battery voltage will do the same thing as is the case with water.

A crude tester would be a 12v light bulb with a couple of wires attached. Put the bulb across the battery and check out the luminance. Take the bulb and with one wire on the battery - terminal, use the other terminal to explore your wiring back to and including the selector (ignition) switch. The light will not be as bright as when directly across the battery, but for a good connection, with the TS function energized, it will still be bright. If it dims down or goes out, you just found your smoking gun.

 

[bazman82]

TS...Thermo Start device.

Think about a water pipe. To get a given flow of water it takes so much head pressure and a certain sized pipe of a certain internal resistance. If you reduce the pressure or the size of the pipe, or the interior of the pipe becomes rough, or in comparing a rough interior to a smooth one, you will have reduced flow.

In electricity, the load (the Thermostart device) requires a certain flow of electrical current to heat to the required temperature to make it work. Bad connections, or corroded wire, or a low battery voltage will do the same thing as is the case with water.

A crude tester would be a 12v light bulb with a couple of wires attached. Put the bulb across the battery and check out the luminance. Take the bulb and with one wire on the battery - terminal, use the other terminal to explore your wiring back to and including the selector (ignition) switch. The light will not be as bright as when directly across the battery, but for a good connection, with the TS function energized, it will still be bright. If it dims down or goes out, you just found your smoking gun.

So I have done the 12v light test before I replaced the Thermo-start. I was getting a bright light from the TS but I didn't check it to the battery itself to see a comparison. I will check this out when I get home and see what happens. I can say it never dimmed down or went out from what I remember.

 

[Texasmark]

So I have done the 12v light test before I replaced the Thermo-start. I was getting a bright light from the TS but I didn't check it to the battery itself to see a comparison. I will check this out when I get home and see what happens. I can say it never dimmed down or went out from what I remember.

Remember, the TS has to be energized....gotta have current flowing.....course, something just hit me. If there is no current flowing, like you don't have continuity all the way from Battery + through the TS circuit wiring to Battery -, there is no voltage drop along the way. The light stays the same brightness all the way down the line, high resistance or not. That's where a multimeter comes in handy as you can go to the Ohms scale and check your resistance from source to load and find a high resistance connection if one exists. Multimeters are readily available and cheap...like I use HF meters and last one i bought was abour 5 bucks and it still works great and that was so long ago I forgot when I bought it. They come with instructions on how to test circuitry with them. Would be worth the investment.

 

[bazman82]

Remember, the TS has to be energized....gotta have current flowing.....course, something just hit me. If there is no current flowing, like you don't have continuity all the way from Battery + through the TS circuit wiring to Battery -, there is no voltage drop along the way. The light stays the same brightness all the way down the line, high resistance or not. That's where a multimeter comes in handy as you can go to the Ohms scale and check your resistance from source to load and find a high resistance connection if one exists. Multimeters are readily available and cheap...like I use HF meters and last one i bought was abour 5 bucks and it still works great and that was so long ago I forgot when I bought it. They come with instructions on how to test circuitry with them. Would be worth the investment.

I have the HF multimeter. Got it free with a coupon I tested the TS (new one) last night with the 12v tester. While energized I am getting a fairly bright light. Maybe only slightly less dim than when I tested the battery +. I know the TS works since I put jumpers on it and it heated up. Any more wiring testing will have to wait though because its been cold out and I would prefer to move my tractor into my little shop before jumping into that. Plus I have lights in there. Its a pain to work on it sitting outside using flashlights and lanterns.

Anyways, sounds like I should be using the multimeter now. I assume I place one point of the MM to the battery + or battery - and the other point on the piece I want to test? I'll have to look up how to tell when I have high resistance though since I don't have much experience with the MM other than if you get numbers then its good and if nothing then its bad...Sorry if it seems like I am asking too many questions, electronics isn't my strong suit and I am more of a hands on learner so I am trying to do my best with how your explaining it.

 

[Texasmark]

If you want to check resistance you put a lead on one end of the circuit/wire/component and the other lead on the other end/terminal/connection. Set the Ohms scale (resistance scale...the Ohm character looks like a tiny pair of headsets on the meter scale) to the lowest Ohm value....probably 200 on your meter...if like mine (Cen-Tech P30756, yellow in color....I think they are red these days.

Turn the dial to 200 ohms scale (which turns the meter on).....don't forget you need a battery in the meter to read ohms.....Touch the meter leads together and read your lead wiring resistance. In the (room temperature) house mine reads 00.4. I just went and got my meter which was outside and with the 30 degree weather, the reading was 00.0....copper has a temperature coefficient which raises its resistance with temperature.

So you have zero checked your meter for a value.... remember it. Then put the leads across the wiring/circuit/component as mentioned above and read the number. Let's say your zero value was 00.4 and you read 01.4 on the scale. That means that you have one ohm of resistance in that circuit. if your reading is 05.4 you have 5 Ohms.

"Ohms law" is described on the www. Pull it up and read it. I don't know the wattage of the TS but since you have the coil wire, as large as it is, glowing red orange (about 500F or so) you are going to be consuming 50 "Volt"-"Amperes" or "Watts" in electrical terms or more (my guess)....look those terms up too.

With the load needing 50 watts to operate correctly and a 12v battery, you will need 50watts/12volts - 4.2 amperes of current flowing from the energizing switch (whatever that is) through the wire to the TS device......that's assuming the interconnecting wiring has zero ohms of resistance....which it won't.

If the wiring circuit resistance is 5 ohms and the needed 4.2 amperes are flowing through it, the wire itself will drop: Voltage drop = ohms x amperes = 5 x 4.2 = 21 volts..........guess what, that isn't going to happen since you only have 12v to start with and the TS device is going to need voltage and current too. I did that deliberately so that you could see the importance of low wiring resistance (ohms) when you are supplying power....watts...volts x amperes......to a load like a TS device that requires a lot of electrical current....amperes.

Now that you have (hopefully) an idea as to what the TS needs, the interconnect from the battery + through the TS complete circuit needs to be on the order of "zero" ohms...theoretically. A 12 gauge (American Wire Gauge) wire will provide that for you with clean crimped contacts that are clean and shiny where they make contact...internal connecting surfaces......a 14 gauge will probably do.

Questions, ask.

 

[bazman82]

Ok, its been awhile again but I finally got the tractor in the shop and got a chance to look more into it today. The key when turned to the correct position does warm up the TS. It stays on for about 20 sec's then shuts off. It takes several times of turning the key to the off position and back on and waiting for the light to go out for the manifold to actually feel warm. I believe I did about 5 cycles. I feel it is not getting fuel to the TS. There is a solenoid on the fuel line connecting to the TS. Is there anyway to test this solenoid to see if its working or not? There is only 1 spot for the wire to connect too on it so I am not sure how to test it.

 

[bazman82]

Did you look for fuel delivery when you replaced the igniter#4?
If you remove the line going to it when you activate the system you should have a steady drip or small flow of fuel to the igniter if not no fire no heat no start.

Just did this today. No fuel from the line when i turn the key to the position. I'll be pricing out the electro-valve and go from there.

 

[bazman82]

Ok, an update for this now. I got the electro-valve (300 bucks ) Of course, the UPS guy leaves the box on the ground like always and the one barn dog chews it all to **** and I find the valve in the middle of the driveway getting covered in snow....That dog is such a pita, its not the first package hes torn up.

Anyways, I replaced the valve and now when I turn the key I hear a click from it. I didn't hear anything from the old one so this was a good sign. I've been trying to bleed out the line with not much success though. I have a few other things I want to try and dumb old me didn't clean the one bolt holding the "In" fuel line while I had it out so I may have to take that back out and clean it up since the hole in it may be plugged. The bottom of the hole in the old valve for that bolt is all cruded up but I didn't see this until a few days after I switched it out. I was trying a few things to bleed any air out and I wasn't getting fuel to the TS at first but then when I disconnected the line from the TS while the engine was idling, it looked wet inside the hole on the TS but nothing dribbling from the line.

Should I take that bolt off and try cleaning it up and try to restart the bleeding process or should I try letting it go for a few more uses and see if itll bleed itself out over time. I remember seeing somewhere that it could quite a few cycles to bleed it all out...

 

[bazman82]

My final update on this. It is working. Not as well as I thought (it takes a few tries) but considering I don't have to use ether when the temp is under 30 degrees is a plus.

The next item to replace is the hydraulic pump and then everything should be good to go!

 

[Texasmark]

If yours is like mine, the diesel return line from the injectors isn't under much pressure so I'd opt for pulling the line where it branches off to the TS and using some carb cleaner, 100# compressed air, and possibly a soft wire, clean the tube on your own. Then connect it back to the source, not the end at the TS switch, and ldle some more till you get a good flow of fluid, not a dribble, a steady stream without any bubbles. Then connect it to a clean inlet connector on your new TS device. Geez I didn't know those things were 300 bucks. WOW!

 

[bazman82]

If yours is like mine, the diesel return line from the injectors isn't under much pressure so I'd opt for pulling the line where it branches off to the TS and using some carb cleaner, 100# compressed air, and possibly a soft wire, clean the tube on your own. Then connect it back to the source, not the end at the TS switch, and ldle some more till you get a good flow of fluid, not a dribble, a steady stream without any bubbles. Then connect it to a clean inlet connector on your new TS device. Geez I didn't know those things were 300 bucks. WOW!

Yeah. The site had it listed at 87 bucks but it was an old posting when i called. She called back with the updated price of 350 and I said no thanks. There were 2 other places that had it for 289 then plus shipping. The line coming from the fuel filter to the solenoid is fairly long, prob about 4ft if stretched out. Maybe I can get to it another time since I have been needing the tractor since the ground finally froze up. I dont doubt that it may need to be cleaned out since the tractor hasnt really worked until I got it.