Agco tractor keeps burning up fuel shutoff soleniod

[Shortylawson]

I have checked everything I found in wiring diagram that ties into soleniod.The soleniod has 3 wires that plug to it.2hot wires & 1ground , but the funny thing is the 2 hot wires tie together just before they get to the soleniod.10 seconds after the tractor started the soleniod is to hot to touch

 

[JerryK]

If it is a sealed unit, just get you a new one. If you can take it apart, you will probably find some crud or rust keeping the 'armature' from fully seating when it is energized. That's usually what makes them hot. They draw a lot of current when they are trying to pull in and seat the armature, just like any coil or relay.. Good luck.... Jerry

 

[ptgdigger]

The 2 hot wires indicate that it is a 2 coil solenoid , internally a larger coil gives it the power to pull the actuator rod in and then a smaller coil holds it, I have no way to tell you which hot is which but the stronger one should be powered only when the key is in "start" and the other one powered by "run", tying the wires together so they are both constant "run" powered will burn out the solenoid. Does the original wiring diagram indicate them tied together ?

Ray

 

[pat32rf]

I'm with ptg on this. On JD they automatically reduce the voltage after a short time lapse. Common problem with them is that they don't get full voltage due to electronic failure and don't pull in.

 

[farmallbill]

just went through this on a truck engine and found that they had a inline resistor that was burnt out and found that the solenoid had never actually failed all problem was in resistor

 

[Johncolleen123]

Hey I am having the same problem. What was your solution. Did you hook up the new solenoid as a 3 way or buy a two coil solenoid

 

[Dave M7040]

I tried finding info on your tractor such as parts diagram, but the best I could do was to find an AGCO web site that needs an owner to go to their dealer and request login name and password so you can look for parts.

My suggestion is for you to do that if you can.

I really dont know where you live, Dungannon Ireland or Dungannon Ontario Canada so this link below may be of no use to you.

Do you have an owners' manual with a wiring diagram which you could scan and send to me?
I will try and help but I need access to information about your tractor.

Dave M7040

AGCO Parts Books

 

[DJ54]

You can gain access by using the guest user portal.

 

[Dave M7040]

I did what you suggested and got into the site.
I found the fuel shut off solenoid and a diode. Both were illustrations or sketches so of little help except to confirm the solenoid has 3 wires and the diode is present.

Thinking Ago did not invent the fuel shut off solenoid I started to look elsewhere for an operating description.

As I see its operation and its three wires, one wire is a ground wire. Is it obvious which one it is?

The other two are two different sources of 12 volt power. One is a low amp one that is powered anytime the engine is running from the run position on the ignition switch. It may have a smaller diameter wire. Is there one wire smaller than the other(s)?

The small wire, assuming one is smaller, goes to the run position on the ignition switch. Once the solenoid has been retracted using a large amount of amps fed from a relay, when the key is returned to the run position, the low amps wire takes over to hold the solenoid so the engine can run.

The high power wire is triggered by turning the key to the start position. The wire from the start terminal on the key switch does not go directly to the solenoid but rather a relay which in turn will send the large amps to the solenoid to get it pulled in all the way at which point the run position and low amp circuit take over.

My suspicion is that the relay which powers the high amp wire has stuck contacts and is continually sending large amp power to the solenoid long after it should have stopped thus cooking the solenoid from the constant high amps going through it.

Do you know which relay powers the fuel solenoid?

I need to hear from you on this before advising you further.

Dave M7040

 

[CADplans]

I just bought a tractor with a dual coil solenoid.
The tractor was setting on the lot with a dead battry.
They said, no problem, they had a "jump box",, it was a big one.
The box spun the engine,, but, it did not have enough voltage to hold the coil.

When I got the tractor home, it would not start, even though the "charged" battery was turning the engine.
I jumped the tractor off my truck, the tractor started right up.

Now, the tractor has a great battery in it,,, it always starts.

So, check your battery,, a 12.5 volt battery might not be enough.
(NOTE: my battery measures 13.2 volts)