# Kubota M-120 Fusible Link



## JMT (Aug 10, 2013)

Had a wire short against the steering wheel tilt mechanism. The Kubota m120 kept running til got back to shop, then would not shut off with the key. Pulled the kill switch to shut it off. Then it would not start again. Found one blown fuse (ENG. CONTROL), and after replacing fuse the tractor would start but did not have head lamps, AC/heater fan, tail lamps, flashers, and still would not shut off when key was turned off. Fuses for lights, AC, ... tested good.

Thought relays might be bad but now think they are ok.

A little more research told me there is a fusible link ("green one" I think) that leads to I think everything that is out. Found a picture in owners manual of the fusible links but could not determine from picture where they are. Could anyone point me to the general location of the links?

Thanks for any help.


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## JD3430 (Jan 1, 2012)

May not be very helpful, but I owned an M-125 that had same problem.
Turns out, the tilt steering can stress the wires along the column, especially if you push down the tilt pedal and "throw" the wheel all the way up. (Not implying you did that).
I am taking it easy on my 126 tilt steering.


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## JMT (Aug 10, 2013)

The corner on the release lever was rubbing on a wire. Guess it pinched it, or just wore through insulation until it shorted. Threw sparks for what seemed like a couple of seconds.


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## somedevildawg (Jun 20, 2011)

JMT said:


> The corner on the release lever was rubbing on a wire. Guess it pinched it, or just wore through insulation until it shorted. Threw sparks for what seemed like a couple of seconds.


I have no idea where it's at, but I can tell you it will be within a few inches of the battery, curious tho...when you "tested" the fuses, did you test them with a test light or did you pull them and check continuity? The reason i ask is...if you had power on both sides of the fuse, you can forget about the link, it's good if that's the circuit.....


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## JMT (Aug 10, 2013)

Found them. Just in front of cab on right hand side. A long ways from the battery. Would have been a lot easier to get to if they were mounted by the battery (and safer).

Good news is that one of them was the problem. Bad news is that I pulled one that just fed the radio so I could make sure that was my problem. In the process I managed to short it against a steel line and burned it up too.

So I went ahead and pulled the one that feeds the ignition switch. Now I have lights and fan but can't start the tractor. Thank you Kubota for putting them in a tight spot behind 3 lines and right where the loader mounts are in the way.


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## somedevildawg (Jun 20, 2011)

I agree, they should be very close to the battery......I've seen some fairly crazy stuff on Kubota


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## slowzuki (Mar 8, 2011)

Unfortunately only recently have tractor designers started planning for a loader mounted on the tractor. I remember doing a starter on our ih584 with a 2250 loader on it, hours vs minutes on the one we had with no loader.


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## Coondle (Aug 28, 2013)

Throw away your fusible links.

I am a convert to automatic reset circuit breakers.

Had a tractor main feed fusible link burn out in middle of hay season at about 10pm at night. Low humidity means much baling and bundling has to happen at night. Lights, starter, everything electrical stopped. Took bad language in torchlight and about an hour to find the culprit. Put some heavy wire in place as a quick fix. Later removed that bridge wire, added two terminals and installed a 40 amp circuit breaker.

You can even get miniature circuit breakers to replace standard spade fuses (not mini spades). Costs a bit for the initial outlay but makes life a lot easier for critical circuits that involve safety. For example I use them on light circuits and electric brake circuits.

If I had tractor AC that would no doubt get a circuit breaker too. Like FI said critical circuits.


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## ARD Farm (Jul 12, 2012)

Back in the day, on road trucks had fuseable links on main circuits, that went the way of the Cat 3406...lol

Now they are all thermal reset circuit breakers. I'd toss the links on the Kubby and install them as well. I think Trucklite has them online.

Speaking of poor designs, I dread changing oil filters on either the M9 or the 105. Both have loaders and both loader frames are smack in the way of the filter. You have to be a contorsionist to get it off...and on and it;s messy. I've never changed the sight glass filter (the spin on fuel filter is as bad as the oil filters) but the sight glass filter is impossible to unscrew without removing the loader frames..... I just hope it never plugs up...


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## JMT (Aug 10, 2013)

How do you determine what size circuit breaker to use?


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## somedevildawg (Jun 20, 2011)

JMT said:


> How do you determine what size circuit breaker to use?


There are several ways but perhaps the easiest is to check the manufactures specs and see what size the fusible link is.....they used to be color coded, not sure if they are anymore. 
Although I think circuit breakers are better, there is no reason that a fusable link will not work. Especially important is to understand why it blew.....they are rated by the amount of current they will pass without failing. They can, with time and constantly running at max load, burn out prematurely. However fusable links are generally the last safety device on the power system wiring. That's why it's usually installed very close to the battery, anything on the battery side of the link is not protected and a short circuit would do a lil welding. Usually in a properly designed electrical system the fuse able links are the last thing to blow, usually real trouble or indicative of an electrical system that is being run at full capacity and is somewhat cheaply designed or has high resistance connections.


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## Coondle (Aug 28, 2013)

Circuit breakers are rated in amps and simple replace a 40 amp fusible link with a 40 amp circuit breaker. Fusible links are opened to break the circuit if too much current flows causing heat in the unit hence the term thermal. When they cool down the auto reset type reconnects, easy. There are manual reset circuit breakers where you push a button to reconnect. My basic lazy approach means I prefer to use auto reset.

If the circuit breaker continues to open the circuit first check you have correct rating and if so look for the actual cause.

High resistance connections are one cause, short circuit or overload are the other causes.


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