Rat Disaster. Need Electrical Help.

[N80]

For the fuel gauge. I have a bunch of those at work, and if it's working sporadically then it's almost always a grounding issue. I've found that making up a jumper wire using a couple of the fork looking butt connectors. And then remove one of the mounting screws from the sending unit. Polish where the screw meets the top of the sending unit with sand paper, reinstall the screw with one end of the jumper. Then find a convenient bolt on the frame and attach the other end of the jumper. Found that this works about 90% of the time. The other 10% is a either a film build up, or diesel booger on the contact.
I hang a couple of old socks with moth balls on my tractor when I store it. One under the hood, and the other gets stuffed under the dash. I just remove them when i use it, and stuff them back up there when I'm done

I've put some mothballs around the tractor but I like the sock trick and will try that.

The ground from the sender is attached to one of the sending unit mounting screws. I used an emory board to scuff up the fork connector etc and it did not help, but I did not do a jumper wire. I will try that.

It looks like a pain to remove the fuel tank to get the sender/float out. I could not believe it was positioned such that the hood hinge pin prevents its removal. The fuel tank only needs to be budged about a half inch for clearance so maybe when it is near empty I'll loosen it and check the float if none of these other things work.

My super cheap multimeter can do DC but all it has is 4 little lights that range from like 600 to 160 volts. So I doubt it will be useful for this low voltage stuff. I think I'll pick up one of the ones that has been suggested.

 

[Dftodd]

There are times I wish I could choke the engineer who designed some things I'm working on. The sending unit I work on ground through the mounting screws, and have a rubber gasket. No way to remove the fuel tank, and the sending unit has a frame rail with about 1 1/2" of clearance above it. Can only get to one mounting screw. The rest are accessed blind with a little 90 degree screw driver. Tech support said to pull the motor to gain access:thumbdown:
I've had good luck with the little cheapy digital multimeter they sell at Walmart. Cost around 10$ and keep it in my service truck. If I lose it, or break it I don't feel so bad. Good luck with it

 

[Dftodd]

Sorry double post, cell phone went on the fritz

 

[N80]

Update. Tried re-grounding the float/sending unit. Nothing. Loosened the fuel tank enough to get the float/sending unit out, took it apart and cleaned it up real good. It is a cheap looking piece of junk. Surprised it worked as long as it did. Made sure the contact points along the rheostat (?) were good. Wired it back up outside the fuel tank and it began working again but was very sporadic in its response to float position which is exactly the way it was before I rewired the dash so I'm pretty sure its the float/sending unit. Will get a price on a new one when I get the chance. I'm expecting to be shocked. The dang breather tube was like $30! (The guy at the tractor place said that this breather tube also fit some New Holland tractors and was closer to $40 so he sells the NH guys the Kubota one.) Anyway, back on topic.....if the new ones are too expensive I'll just leave it alone. When I was looking at used tractors way back when I saw one with a wooden dowel hanging from the throttle leaver. When I asked the owner what it was he said "fuel gauge".

 

[crazyal]

Actually that one looks to be pretty good quality. the ones I've messed with have wire wrapped around a non electrically conductive material and the wiper arm rubs against it. The wire gets worn or breaks and then the gauge stops working. I'm guessing that mfgs assume that fuel will lubricate the wiper to keep it from wearing out.

 

[Coyote machine]

Here is an alternative source for fuel gauge senders of various arm lengths for different tank depths, etc. They're mostly universally compatible with the gauge's rated Ohms range. Marine and RV spec, will not rust, and better quality than your OEM sender unit. Talk to their sales people about what model would work for your hole pattern, usually 5 hole pattern in the tank.
Electric Sending Unit, 6" to 12" Tank Depth #35722-10

 

[TomSeller]

Here is an alternative source for fuel gauge senders of various arm lengths for different tank depths, etc. They're mostly universally compatible with the gauge's rated Ohms range. Marine and RV spec, will not rust, and better quality than your OEM sender unit. Talk to their sales people about what model would work for your hole pattern, usually 5 hole pattern in the tank.
Electric Sending Unit, 6" to 12" Tank Depth #35722-10

I notice on one of the PDFs linked in the page they say for gasoline but reference diesel "if a separate return line is available". Not sure what that means. Fuel return off of the injectors?

 

[N80]

Here is an alternative source for fuel gauge senders of various arm lengths for different tank depths, etc. They're mostly universally compatible with the gauge's rated Ohms range. Marine and RV spec, will not rust, and better quality than your OEM sender unit. Talk to their sales people about what model would work for your hole pattern, usually 5 hole pattern in the tank.
Electric Sending Unit, 6" to 12" Tank Depth #35722-10

Thanks for the link. For under $30 it would certainly be worth a try.

 

[N80]

Error-double post.

 

[TomSeller]

Thanks for the link. For under $30 it would certainly be worth a try.

I noticed on one of the PDFs linked in the page they say for gasoline but reference diesel "if a separate return line is available". Not sure what that means. If you use one and figure out what they are talking about, I would appreciate knowing. It would not seem to me that the fuel would make a difference as long as it is compatible.