Another Kubota fuel gauge stuck on full

[srs]

James, yeah today I worked my butt off trying to figure things out. I even took the seat out (no picture) because the wiring harness ran up under the seat area and I thought I could find some wires there. I too might just throw the towel in. I'll take some pictures of the sending unit to show everyone. I was thinking that maybe I should just buy a new sending unit. I contacted Messick'a part department and they indicated that any electrical device purchased and installed cannot be returned. So perhaps a new sending unit would work and then again most likely (in my opinion) it would not. I would be out $50.00+.

I once again want to thank you and the other fine members of TBN for all of your help and support. I'll try to get some pics Weds. night and hopefully can take some close-up shots of the interior of the sending unit. Not much to it! Stanley

 

[crazyal]

On part C you said you were a little confused. Did you disconnect the wires going to the sensor before you read the resistivity between the center connector the yellow wire goes to and the side terminal where the black wire connects? How full is your tank, close to full? If unsure can you look into the tank and tell? A reading of 6 ohms is very close to 4 ohms (full tank). I doubt you could see a difference on the dash fuel gauge between 6 and 4. If the wires were disconnected when you got a reading of 6 I would say your sensor is indicating a full tank. If the tank is not full then I think you have a bad sensor or the float is sticking.

 

[number two]

My WSM calls for 1-5 ohms at upper-most position and 103-117 ohms at lower-most position for the sending unit test.Sounds like the sending unit is OK!I have no way to send the wiring diagram to you guys.Could Messicks or local dealer provide one?I'd be happy to provide wiring info-my time is limited though-be patient!Could it be time to run bypass wires yet?Don't give up-my tractor may be next!

 

[k0ua]

My WSM calls for 1-5 ohms at upper-most position and 103-117 ohms at lower-most position for the sending unit test.Sounds like the sending unit is OK!I have no way to send the wiring diagram to you guys.Could Messicks or local dealer provide one?I'd be happy to provide wiring info-my time is limited though-be patient!Could it be time to run bypass wires yet?Don't give up-my tractor may be next!

Number two... where does the yellow/blue wire go.? and does the black wire go directly to ground? On my Kioti tractor it is complicated the circuitry goes to a module, apparently an IC with a lot of functions. how does this circuit work. Can you scan in the page with a scanner and post it as a .jpg?

 

[crazyal]

My WSM calls for 1-5 ohms at upper-most position and 103-117 ohms at lower-most position for the sending unit test.Sounds like the sending unit is OK!I have no way to send the wiring diagram to you guys.Could Messicks or local dealer provide one?I'd be happy to provide wiring info-my time is limited though-be patient!Could it be time to run bypass wires yet?Don't give up-my tractor may be next!

On his last test he got a reading of 6 when the sensor was in the tank. That would indicate a full tank, if it's not full that's telling me that something is going on with the sensor.

 

[number two]

James-My WSM wiring diagram shows a yellow wire from the guage to the center pin of the sending unit;black wire does go to ground.Thanks for your help and interest in this thread.Best Wishes!

 

[srs]

On part C you said you were a little confused. Did you disconnect the wires going to the sensor before you read the resistivity between the center connector the yellow wire goes to and the side terminal where the black wire connects? How full is your tank, close to full? If unsure can you look into the tank and tell? A reading of 6 ohms is very close to 4 ohms (full tank). I doubt you could see a difference on the dash fuel gauge between 6 and 4. If the wires were disconnected when you got a reading of 6 I would say your sensor is indicating a full tank. If the tank is not full then I think you have a bad sensor or the float is sticking.

Al, I removed the sending unit from the tank and the tractor wires were disconnected from it. The tank is approximately 1/2 full. I'll try this test again sometime later in the day and test the sending unit on the workbench. I'm also going to cable tie the float arm in the empty position and reinsert the sending unit in the tank and install as normal to see what the fuel gauge indicates. That would be too easy of a fix but would be nice if the fuel gauge showed empty. Remember the fuel gauge after all these years just started to peg itself at the full mark.

My WSM calls for 1-5 ohms at upper-most position and 103-117 ohms at lower-most position for the sending unit test.Sounds like the sending unit is OK!I have no way to send the wiring diagram to you guys.Could Messicks or local dealer provide one?I'd be happy to provide wiring info-my time is limited though-be patient!Could it be time to run bypass wires yet?Don't give up-my tractor may be next!

I'll email Messicks later and see if they can email me the wiring diagram. Doubt it though!

 

[radioman]

If I were you - I'd establish a new ground -- just add another wire from sending unit to new ground spot. check to see if this is resolved. If not - run a new wire from postive on sender to the dash board or where it ends up. check. if it resolves - pull the new ground out. check. still resolved? then you know the wire had a break in it somewhere - time for a rewire. if both ground and positive needs replacing - we need to figure out how both got pinched and has bad connection - either way - its time for a rewire.

 

[srs]

If I were you - I'd establish a new ground -- just add another wire from sending unit to new ground spot. check to see if this is resolved. If not - run a new wire from postive on sender to the dash board or where it ends up. check. if it resolves - pull the new ground out. check. still resolved? then you know the wire had a break in it somewhere - time for a rewire. if both ground and positive needs replacing - we need to figure out how both got pinched and has bad connection - either way - its time for a rewire.

radioman, I did try to run a new ground (I think) but will do it again. If that is no good I'll go to running a wire from the positive on the sending unit directly to the fuel gauge. God I hope this works! Appreciate your feedback.

 

[srs]

Ok guys it appears to be fixed! Here is what I did today. I first tried the suggestions by radioman with no luck, but thank you anyway.

The sending unit was out of the tank and for the heck of it I tested the ohms readings while it was on the workbench. It registered correctly. So while the sending unit was out of the tank I decided to drain the diesel from the tank. I stuck a plastic hose in the tank and sucked to get a gravity feed of diesel to go into my fuel container. I removed I'm guessing about 3+ gallons of fuel. The fuel tank is now very low and near empty. I decide to put the sending unit back in the tank. I connected the factory wires to the sending unit and turn the key on and the fuel gauge reads empty, h'mmmm! I take a piece of wire and insert it into the fuel neck opening and I was able to move the float up and down and the fuel gauge moved accordingly. Leaving the key at the on position I then start to refill the tank adding 3 gallons or so and as I do I'm watching the fuel gauge gradually rise to about 5/8th's full. I switch the key to off and the fuel gauge gradually drops to empty. I turn the key back on and the fuel gauge goes back up to about 5/8th's full. James (k0ua) had suggested in post #4 that perhaps the float was stuck. I'm thrilled even with diesel fuel on my breath, ha!!!!

I can't thank everyone enough for their kind support and suggestions and hanging in there with me. Believe me I was "that close" to hanging it up. Hopefully I can return the favor to my fellow TBN members in the future.