Somehow I am frying my throttle cables. I have replaced three of them and they aren't cheap. I install them right but the moment I go out into the pasture and run the tractor for about 20-30 minutes and then go to throttle down, it won't work. When I pull the throttle cable off it is like frozen within the sheath. Someone suggested that the ground on the little tractor might not be working and that the ground was running through the cable fusing cable inside the sheath. I just can't seem to figure out why the ground would not be working. any ideas.......
G1900 Throttle troubles
- Thread starter moralem
- Start date
It seems that on every tractor I have owned I always end up running a seperate ground from the battery to one of the starter motor mounting bolts. I need to make a better effort to keep my connections.
Dusty
Dusty
I don't Know. What else could it be. Unless the cable is close to a heat source and even then it should show damage from the outside. A live wire shorting against the cable itself? Moralem and Eric should get together and discuss this. I hate wiring so bad that I would just disconnect or cut everything but the starting circuit and then reconnect one at a time till the problem shows itself. Maybe its just because everything I own is old but those extra grounds seem to eliminate a lot of starting issues. Did I tell you I hate wiring. Dusty
DustyI thought it might be that it was too close to a heat source but made sure it was far enough away from anything that could cause that kind of fusing. My current ground connections look good but I can't really tell because one of the wires that is connected to the ground bolt runs back up into a wire harness and it is almost impossible to trace it to the other end. I will try running another ground wire from the battery to the starter mount and see what happens, but another 40 bucks is hard to take just to experiment. How would I check with one of the old fused cables to see if current was running through it.....any ideas would be appreciated.
Hey Moralem. I am sorry, you don't have to install another ground. On these old tractors they ground the battery to the rear housing, right beside the battery. The ground path from the ground on the rear end to the starter may not be as good as when the tractor was new. It is just like with welding the closer the ground is to where you are welding the easier the current can flow. If your normal ground on the tractor is clean and I mean take it off and clean it again clean, then you should be good as far as a main ground. There is a guy on here named Traildust and he is a whiz on wiring. There are others too. I am not sure if Service dept Vic misunderstood and thought it was my tractor. Cause he seems to be under the impression that I know what the hell I'm talking about. I was just trying to help but I may have caused more harm than good. Vic is a kubota Guru. Well he will check this thread again.And chances are so will traildust. Sorry if I caused any grief. Dusty
Ive seen it happen several times with throtle and choke cables on petrol vehicles,the centre wire acts as an earth especially when cranking it heats up the antifriction lining which melts then cools down goes solid and grabs the centre wire.
Dave
Dave
Yup that is what is happening, I dissected the cable and it does have the antifriction lining inside but I can't find where on the cable it is fusing. Now I need to figure out how to get the cable to not act as a ground wire......any other suggestions other than checking and cleaning the current ground. The ground for the battery is connected to the front of the frame and the harness ground is run to the same bolt on the frame. So I will clean it up and see what happens. Is it the ground from the battery that I should try to troubleshoot or is the other smaller black ground wires that are bundled in a wire hireness that I should be paying more attention to..........Thanks to all for the help. I know there is a solution out there now to just find it without having to resort to taking it to dealer for what I am sure will be hours of diagnosing.............
All very good suggestions so far.
I'll try to keep from rambeling but for some reason I like this thread, so forgive me
One of the ideas, a heat source causing the damage is possible. As soon as you noticed the problem did you by chance feel the cable in heat exposed areas to see if the cable was hot to touch?
As far as the cable being used as a "ground" that is also very possible. IN order for current to flow there must be a circuit. Both ends of the cable would have to bond with something that is able to complete the circuit to ground. The first one is obvious and is at the engine hook up. The next location would have to be the throttle lever device.
I think this is why some control cables have teflon or plastic type insulators at one or both ends to prevent current from flowing through the cable.
I looked at this part diagram on the colemanequip site and I am unable to determine if such insulation is provided at the throttle lever. Are you able to inspect this linkage to see if you have any worn or missing devises intended to insulate against current flow?
If there isn't, than quite possibly you could make your own. Go to the auto parts store and look for small enough teflon type washers to place inbetween the clevis and linkage arms. If not able to do that, how about a pice of electric tape to the top and bottom on the inside of one end of the clevis. Of course now you would have to replace the pin that secures the clevis with a non metallic type. If you are able to comply with this than you would break the circuit and current can not flow through the cable.
I would think a non mettalic tefflon pin would be ok since the friction you feel in the accelerator lever is a "load feel" set at the lever and the cable linkage is not actually having to transmit the same force.
For curriosity sake, you can see if and just about how much current the cable is carrying. First we can see if the cable is bonded with the tractor. Disconnect the clevis from the engine and using a meter set to ohms touch one of the leads to the clevis and the other to a good ground. How much resistance do you have, if any. This will let us know if the throttle linkage is bonded with the tractor. If it is then it is going to carry a certain amount of current when hooked up to the engine side.
By default if the cable is indeed bonded from the engine and completing a circuit with the throttle lever using a meter to check for voltage isn't really gonna do much good. No matter how small the amperage the meter will always say 12v dc.
One way to see just how much is going through there is to get a test light. Any light will do but something like a tractor add on light would be best. At least something in the neighbor hood of 50 watts. This will equal ablut 4 amps. It will most likely take a lot more than that to weld the inner parts of your cable.
Set the light up safely with long enough jumpers. Connect one end to the positive terminal of the battery and the other end to a clevis on the cable. The best location would be the clevis on the throttle control linkage. Be careful with this and provide good safety measures for yourself by maybe even splicing in a fuse for the test light and a switch. It's easy and most people might even have extras of this stuff in there garage.
With this hooked up, turn on the ignition but not the engine yet to see if it illuminates. Whit a helper, start the engine and see what the light does while cranking. What doe it do after the engine has finished cranking and is running?
One other possibilty with a new cable is to leave it disconnected from the engine side. Wrap the clevis and any metal on the cable with tape to insulate it and safely secure it. Now the tricky part. Fabricate a way to either control the engine side with a stiff cable to the driver or safely secure the engine linkage so the engine doesn't go whide open uncontrolable on you. Now go out and drive the tractor for a while and bring some adult beverrages with you.
When you are done, inspect the control cable to see if it is damaged like the others. If it is than this is not from current flowing through it. This would have to be heat damage.
Sorry that ws so long and I hope it ws of some help.
I'll try to keep from rambeling but for some reason I like this thread, so forgive me
One of the ideas, a heat source causing the damage is possible. As soon as you noticed the problem did you by chance feel the cable in heat exposed areas to see if the cable was hot to touch?
As far as the cable being used as a "ground" that is also very possible. IN order for current to flow there must be a circuit. Both ends of the cable would have to bond with something that is able to complete the circuit to ground. The first one is obvious and is at the engine hook up. The next location would have to be the throttle lever device.
I think this is why some control cables have teflon or plastic type insulators at one or both ends to prevent current from flowing through the cable.
I looked at this part diagram on the colemanequip site and I am unable to determine if such insulation is provided at the throttle lever. Are you able to inspect this linkage to see if you have any worn or missing devises intended to insulate against current flow?
If there isn't, than quite possibly you could make your own. Go to the auto parts store and look for small enough teflon type washers to place inbetween the clevis and linkage arms. If not able to do that, how about a pice of electric tape to the top and bottom on the inside of one end of the clevis. Of course now you would have to replace the pin that secures the clevis with a non metallic type. If you are able to comply with this than you would break the circuit and current can not flow through the cable.
I would think a non mettalic tefflon pin would be ok since the friction you feel in the accelerator lever is a "load feel" set at the lever and the cable linkage is not actually having to transmit the same force.
For curriosity sake, you can see if and just about how much current the cable is carrying. First we can see if the cable is bonded with the tractor. Disconnect the clevis from the engine and using a meter set to ohms touch one of the leads to the clevis and the other to a good ground. How much resistance do you have, if any. This will let us know if the throttle linkage is bonded with the tractor. If it is then it is going to carry a certain amount of current when hooked up to the engine side.
By default if the cable is indeed bonded from the engine and completing a circuit with the throttle lever using a meter to check for voltage isn't really gonna do much good. No matter how small the amperage the meter will always say 12v dc.
One way to see just how much is going through there is to get a test light. Any light will do but something like a tractor add on light would be best. At least something in the neighbor hood of 50 watts. This will equal ablut 4 amps. It will most likely take a lot more than that to weld the inner parts of your cable.
Set the light up safely with long enough jumpers. Connect one end to the positive terminal of the battery and the other end to a clevis on the cable. The best location would be the clevis on the throttle control linkage. Be careful with this and provide good safety measures for yourself by maybe even splicing in a fuse for the test light and a switch. It's easy and most people might even have extras of this stuff in there garage.
With this hooked up, turn on the ignition but not the engine yet to see if it illuminates. Whit a helper, start the engine and see what the light does while cranking. What doe it do after the engine has finished cranking and is running?
One other possibilty with a new cable is to leave it disconnected from the engine side. Wrap the clevis and any metal on the cable with tape to insulate it and safely secure it. Now the tricky part. Fabricate a way to either control the engine side with a stiff cable to the driver or safely secure the engine linkage so the engine doesn't go whide open uncontrolable on you. Now go out and drive the tractor for a while and bring some adult beverrages with you.
When you are done, inspect the control cable to see if it is damaged like the others. If it is than this is not from current flowing through it. This would have to be heat damage.
Sorry that ws so long and I hope it ws of some help.
I made my previous post and noticed your update. Some of my last post may not apply any more. Sorry.
Thanks for all the input, I am going to try all of the electrical troubleshooting you suggest. My first hunch was that it was electrical but I have no understanding of electrics to even begin to troubleshoot, but your suggestions all sound very doable and give me a place to start. It has remained in the back of my head that another heat source might be the trouble as well since the very original cable was very hot when I went to touch it. It is one of those old types that the metal casing is not covered in plastic. When I pulled it off and burned my finger I first thought that the engine bay area was getting too hot but I just couldn't understand how since the tractor runs cool but then my thermostat could be wrong. I will get back and let everyone know what is happening.
You are welcome and I hope it uesful to you.
Like dusty mentioned, check the ground cable fromt the battery and if at all in doubt, replace the cable.
Here is something else you can do and it's pretty easy. Do you have any of those digital thermometers that have a silicone cable and temp probe on the end? Just about anybody who BBQ's will have at least one or two (I have 5).
Secure the probe in the area of the cable you belive to be getting the hottest when the trouble happens. Try not to let the probe tip touch the cable as we want to measure the air and see if it's actually getting hot enough in there. If you have another one of those thermometers, secure the temp probe as best you can so that it does actually measure the temp of the cable. Route both LED indicators to a location you can see the temps while driving the tractor.
This way, as you are driving around you are able to monitor the air temp near the cable and also monitor the temp of the cable.
Do you have a hand held infrared thermo scanner? The type that shine a red lazor dot on the exact location checking for heat. If you do, then great. If not then they sell them for a very low cost now at the auto part stores. I bought one several years ago and payed a couple hundred dollars. Now they cost so much less and I've seen them under $20.
With that tool you will be able to find any hot spots from the engine and cable while stopping for periodic testing.
Also keep in mind that thremostat and temp indicator, if installed, will only indicate the coolant temps. There could be other areas of the engine getting really hot but if you have an outstanding coolant system you would probably never know until something happened.
Good luck and have fun but most of all please be safe!
Like dusty mentioned, check the ground cable fromt the battery and if at all in doubt, replace the cable.
Here is something else you can do and it's pretty easy. Do you have any of those digital thermometers that have a silicone cable and temp probe on the end? Just about anybody who BBQ's will have at least one or two (I have 5
).Secure the probe in the area of the cable you belive to be getting the hottest when the trouble happens. Try not to let the probe tip touch the cable as we want to measure the air and see if it's actually getting hot enough in there. If you have another one of those thermometers, secure the temp probe as best you can so that it does actually measure the temp of the cable. Route both LED indicators to a location you can see the temps while driving the tractor.
This way, as you are driving around you are able to monitor the air temp near the cable and also monitor the temp of the cable.
Do you have a hand held infrared thermo scanner? The type that shine a red lazor dot on the exact location checking for heat. If you do, then great. If not then they sell them for a very low cost now at the auto part stores. I bought one several years ago and payed a couple hundred dollars. Now they cost so much less and I've seen them under $20.
With that tool you will be able to find any hot spots from the engine and cable while stopping for periodic testing.
Also keep in mind that thremostat and temp indicator, if installed, will only indicate the coolant temps. There could be other areas of the engine getting really hot but if you have an outstanding coolant system you would probably never know until something happened.
Good luck and have fun but most of all please be safe!
As I see this, there are 3 possible causes:
1. heat form exhaust..possible but highly unlikely Kubota would be aware of this problem and fixed it.
2. throttle cable touching bare live wire and earthing out..possible but the live wire should also heat up and burn the insulation/blow fuse
3. Bad connection of main battery earth cable..Most likely cause...
You could test this by disconecting the throtle cable at both ends and see if the starter cranks the engine ok but the danger in this is a weaker wire could be used as another earth and get so hot it could burn out and melt.. so as suggested you need to clean the end of the battery lead where goes to the frame/cab and any earth bonding cable between the frame/cab and the engine
You should be able to test the conductivity of the earth cable with an ohm meter..clamp one probe of the meter on the -ve (earth) bat terminal then touch the other probe on the end of the bat lead where it bolts to frame and if it has low resistance its ok..then move the probe to the frame,if low resistance its ok,if high resistance it needs cleaning..do this all the way to the starter motor housing and once you have low resistance all the way you should be good to go!
Dave
1. heat form exhaust..possible but highly unlikely Kubota would be aware of this problem and fixed it.
2. throttle cable touching bare live wire and earthing out..possible but the live wire should also heat up and burn the insulation/blow fuse
3. Bad connection of main battery earth cable..Most likely cause...
You could test this by disconecting the throtle cable at both ends and see if the starter cranks the engine ok but the danger in this is a weaker wire could be used as another earth and get so hot it could burn out and melt.. so as suggested you need to clean the end of the battery lead where goes to the frame/cab and any earth bonding cable between the frame/cab and the engine
You should be able to test the conductivity of the earth cable with an ohm meter..clamp one probe of the meter on the -ve (earth) bat terminal then touch the other probe on the end of the bat lead where it bolts to frame and if it has low resistance its ok..then move the probe to the frame,if low resistance its ok,if high resistance it needs cleaning..do this all the way to the starter motor housing and once you have low resistance all the way you should be good to go!
Dave
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Thanks to all for the suggestions. I finally was able to determine that the ground was faulty. I replaced the ground battery cable with a new one and added a ground strap as well from the engine to the frame. The tractor ran fine and I was able to mow my long overgrown pasture. It seems a secondary ground was missing. Of course my saga does not end here becasue when I added the ground strap I made the mistake of not making sure that it did not come in contact with any metal and the ground strap arced to the hood of the tractor and melted the cable again!!!!!!!!. That is when I went out and got a custom cable made for it at the New Holland dealer ha ha, and made it so short that it had no room to move and it was also insulated. So far no more arcing but I am still waiting on a new cable from Kubota, seems they are made in Japan. Anyway it seems like my electrical problems are solved for now but won't really know until I can get the new cable, but since it worked previously it should be good to go.
Now, for my next problem. The darn thing is overheating and it is a gradual process. It will take it about an hour to an hour and half before it hits red on the gauge, then the horn under the seat goes off. The radiator had a leak last year but that was fixed and at that time it was also cleaned out. The belt is tight and the radiator screen is cleaned regularly while I mow but it still over heats. I have not changed out the thermostat because my thinking is if it was bad it would not take the tractor almost two hours to overheat. The dealer suggested that I try a new radiator cap which is on order as well. But I find it hard to beleive that a bad cap would cause it to gradually overheat , but what do I know. The only other thing I can think of is a bad water pump but I would have no way of knowing how to even begin to diagnose that and I would hate to just thow a new costly pump at the prolem without knowing if that is in fact the problem. Okay folks, I am looking for your great input again.......what is happening here other than I am cursed or mowing on sacred burial grounds.
Now, for my next problem. The darn thing is overheating and it is a gradual process. It will take it about an hour to an hour and half before it hits red on the gauge, then the horn under the seat goes off. The radiator had a leak last year but that was fixed and at that time it was also cleaned out. The belt is tight and the radiator screen is cleaned regularly while I mow but it still over heats. I have not changed out the thermostat because my thinking is if it was bad it would not take the tractor almost two hours to overheat. The dealer suggested that I try a new radiator cap which is on order as well. But I find it hard to beleive that a bad cap would cause it to gradually overheat , but what do I know. The only other thing I can think of is a bad water pump but I would have no way of knowing how to even begin to diagnose that and I would hate to just thow a new costly pump at the prolem without knowing if that is in fact the problem. Okay folks, I am looking for your great input again.......what is happening here other than I am cursed or mowing on sacred burial grounds.
Are you mistaking what the ground strap/cable is? the ground cable on a kubota goes to the negative terminal which is smaller and should be in contact with the frame of the tractor and so should make no difference if it touches any other bare metal cos it isnt live... now if your talking about the LIVE lead ( the positive larger terminal)from the battery to the stater motor/solenoid ..thats a different matter,it should never touch bare metal.
Dave
Dave
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Well for some reason my ground strap from the frame to the frame/engine carries a charge for some reason. I have a short somewhere and I can't figure it out. The ground strap is arcing for some reason. I get my new cable soon so I will install it and see if it fries again, but I did not connect the ground strap to the positive of the battery.
Just reading over everything that has been posted so far. It sounds like you have your hands full. I can't help but wander if your tractor is really overheating or if your electrical problems are making your heat guage give you a faulty reading. One of those heat guns that Traildust mentioned earlier would be nice to confirm this for you.
For a wire the thickness of an earth cable to burn up means there is a dead short from the positive side of the battery which is fed by a thicker wire than the earth lead .if you install a thicker new earth cable without finding the short first you could end up burrning up the whole wiring loom and if luck is against you,setting your tractor on fire.
Dave
Dave
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I thought that might be the problem but when it overheats not only does the gauge indicate overheating but the horn that is supposed to warn you of overheating goes off as well.And the fluid in the overfill tank is boiling. But I am going to try one of those heat guns on the radiator and see what is happening.
I never thought of that one. I am at a loss for diagnosing the short problem but also have a Kubota, straight from Japan, ground cable coming in the mail and I am going to switch out the 10 gauge cable that is on there with the stock ground cable from Kubota and see what the heck happens. I will let you all know what happens, it just might go up in smoke. I guess what started out as a bargain tractor has turned into the tractor from hell. Now I know why the old timer sold it to me for 600 dollars american............
I don't really think you are cursed. If that were so you would have a green mower.
I have seen this happen before. A friend of mine had a Freightliner road tractor with a leak in the radiator. The shop that fixed it stuck it to him bad. Instead of doing the job right they just pinched off the tubes where the leak was at and sealed them up. The only thing this did was make his radiator unable to have enough capasity to keep his engine cool. This shop called that fixing a leak.
As far a the radiator cap goes. I went thru this with my B 7100. On a warm day it would overheat and blow the water out the overflow tube. I tried everything and in the end I replaced the cap and it was fixed. It can happen.
Just for the sake of asking have you traced the cable that goes to the starter?