B7510 - Trying to understand Fuel Solenoid

[Trent]

First of all, there is nothing wrong with my tractor.

My concern is having something fail, having the solenoid drop out while using the tractor and not being able to get it back to the house.

After about an hour at my local "you pull it" junk yard, I found what looks like an exact match for the electrical plug on the solenoid.

My plan is to have a way to energize the solenoid from the battery in an emergency, without disturbing any of the existing wiring. I'm assuming 12VDC on the 2 conductors....


Does this sound like something that would work, just to get the tractor back to the shop/house? Is there a better way?

Thanks, Trent

 

[L4740]

Good to hear there is nothing wrong with your tractor. But if I understand you correctly you are concerned that if your 12v goes away, your tractor will die and you cannot get back home. Good news...if your 12v dies, your tractor will not die, you can drive it for as long as you wish. However, the next time you go to start it, it will not start. Your fuel solonoid needs 12v to shut off, not to shut off. So no need to be concerned about not being able to get home. You will have more concern after you get home and can't shut it off!

 

[North Idaho Wolfman]

L4740,
Sorry to disagree with you but a B7510 has a solenoid setup that needs to be energized to run.
Your L4740 and my l3450 is the opposite, it needs power to shutdown, hence why you have a manual override shutdown lever, his tractor does not have that.

So yes Trent if you energize the solenoid (put an 20 amp inline fuse) you could limp it home, but most commonly when the system goes down it's the actual solenoid that is the problem.
You can just unbolt it, cut off the rod, reinstall and it will start and run.

 

[L4740]

Don't be sorry for providing correct information. I didn't reallize that had changed the operarion of the fuel solonoid. They say you should try to learn something everyday. So I guess my day is complete.

 

[lugbolt]

what if the solenoid dies?

If I remember correctly, there are 2 coils inside of it, one "pulls" the plunger, and the other "holds" it. The pull coil pulls more juice and overheats if left with 12v on it all the time. The other is designed to stay energized for long periods of time without problem. It is self-grounding.

If the solenoid dies, and won't pull the plunger in, then you're just screwed. Take the solenoid out of the block and replace it with a new one....and it's not uncommon for them to die. Maybe keep a spare, and a 10mm socket, in the tool box? I'd be less worried about an electrical system problem than the solenoid itself failing.

But your idea does sound like it'd work...until an emergency situation happened, then the engine would continue to run until +12v was removed, manually, which is hard to do when you're wrapped around a PTO shaft or pinned under a roll bar. Just something to think about.

 

[GWD]

Not exactly sure on your tractor, but if the solenoid stops working, the rod can be disconnected and the default position of the solenoid might be that the fuel line is open.

You might hear a "click" about 10 - 15 seconds after shutting down thus indicating it the solenoid is returning to the open position after being closed for shut down.

To make sure, check the solenoid rod position when the tractor is running. Then shut it down and see where the rod position is then. Wait a minute to see if it resets. Next, disconnect the rod and see where the shut off valve (not the solenoid arm) defaults. If it is "fuel line open" then you have an easy work-around in case of failure. Just pop off the rod.

If the valve defaults to "fuel line closed" then maybe a piece of bailing wire can be rigged to make it in the "open" position. Another easy work-around.

At any rate, a new solenoid will be necessary.

 

[North Idaho Wolfman]

Trent,
Sorry your getting some inaccurate info!
You tractor has an Internally actuated stop solenoid, the stop rod engages the fuel injector pump rack to push it to a stop position.
If it's a single coil or dual coil, I'm not sure, # of conductors (wires) will answer that, Single conductor single stage, dual conductors dual stage, There is some exceptions, and where there are three conductors that will also be a dual stage with a ground conductor.

There is no "bailing wire it open" to make it work scenario.

Just remove the solenoid and it will run, simple as that.

 

[GWD]

Trent,
Sorry your getting some inaccurate info!
You tractor has an Internally actuated stop solenoid, the stop rod engages the fuel injector pump rack to push it to a stop position.
If it's a single coil or dual coil, I'm not sure, # of conductors (wires) will answer that, Single conductor single stage, dual conductors dual stage, There is some exceptions, and where there are three conductors that will also be a dual stage with a ground conductor.

There is no "bailing wire it open" to make it work scenario.

Just remove the solenoid and it will run, simple as that.

You must have missed the "IF" in my post. Two options on the operation of the stop solenoid were given. Choose the one that works for the particular tractor model.

Others, with different tractors, may read the post as well and benefit from the options.