TC33D Keeps going through fuel shutoff solenoids

[jcoop1]

Check wiring 12Vdc at solenoid when key is on
Check Fuse, fuse good, 12Vdc at solenoid when key is on
Install, pretty straight forward, unscrew old one, screw in new one. One wire so no way to connect it wrong, No adjustment that I can see.

Not trying to be a smart *****, just there is not alot to go wrong here. Think I am just getting crap solenoids. ordered one from NH, we will see.

John

 

[CalG]

If the solenoid is a one wire type, it should NOT BE ENERGIZED constantly. There must be a "control module" that is supposed to energize the the fuel cut off for a brief time period after the key is turned to off.

Check the wiring diagram to see what goes where.

I will say, I know nothing about the TC33D, but I had similar issues with my SDF. It's on a mechanical pull rod fuel shut off now! KISS

 

[thepumpguysc]

What I'm hearing is> the sol. is energized to shut off?? vs. energized to run..

I've read this over & over & I'm still confused unless u come back w/ "energized to shut off"..
U said, u have to unscrew it to get it to shut off..
IF its energized to S/O, then there shouldn't be voltage to it while the engine is running..
Are u putting the washer on the sol. where it meets the block.?? The washer acts like a spacer/shim.

 

[TnAndy]

What I'm hearing is> the sol. is energized to shut off?? vs. energized to run..

I've read this over & over & I'm still confused unless u come back w/ "energized to shut off"..
U said, u have to unscrew it to get it to shut off..
IF its energized to S/O, then there shouldn't be voltage to it while the engine is running..
Are u putting the washer on the sol. where it meets the block.?? The washer acts like a spacer/shim.

Confused here too.

If it's energized to SHUT OFF, where does the power come from, and when does it stop being applied ? Surely it doesn't sit in an energized state while the tractor is not running ? You've checked this by seeing there is NO voltage on that single wire connection with the engine running ?

I always thought they had power applied to hold the rod IN while the engine was running, and when power was cut (turn key off), a spring forced the rod forward, stopping fuel flow. Seems that is the only way yours could get hot....that constant application of power while running....something is wrong with the amount of power applied (though since the fuse doesn't blow, that shouldn't be it)(you're SURE you don't have an over sized fuse), or it's simply a crappy design.

I'd be tempted to cut one or two of the old ones open and look at it. Look for corrosion on any electrical contact points inside. Maybe the spring is just slightly TOO strong, and trying to force the rod forward, causing the contact points for the magnetic coil to heat up because they aren't making good contact all the time.

One last thought would be bad grounding. Perhaps the engine is not grounding well back to the battery. I'd be tempted to find a screw on the engine close to the mounting point of the solenoid, back it out and clean under it to bare metal, then run a temporary wire from it to the negative side of the battery and see if that stops the solenoid from heating up. And check the negative terminal on the battery is clean, and the other end of the negative lead is corrosion free and well attached to the frame/etc.

 

[Eagleview]

Just a single wire to the solenoid 12vdc.

Once it dies it is dead, solenoid it very hot, but even when it cools off it does not function. Have went through at least 4 of these over the last 6 months, really thought this one was going to last.

Fuse does not blow.

Please keep the ideas coming

Is it the type with a pull rod that actuates the stop lever ?
If so, they must be adjusted so the solenoid plunger goes all the way back to its internal stop . If it is not on the stop, the winding's just get hotter and hotter as the TRY to pull the plunger back . This is why they burn out .

 

[ruffdog]

Are u putting the washer on the sol. where it meets the block.?? The washer acts like a spacer/shim.

The washer part #SBA025100016

 

[jcoop1]

It does have the washer/spacer.

when key is on there is 12vdc to the solenoid, this RETRACTS the solenoid. By "unscrewing" it you are mimicking the solenoid retracting thus allowing the fuel to flow to the engine.

 

[jcoop1]

if there was no solenoid on the motor you could start it and it would not shut off until you reinstalled the solenoid and had the key off. You could also push the lever in that is inside the pump to shut off.

 

[barbqranch]

Measure the voltage at the solenoid when it is running. Oddly enough, low voltage can cause overheating, if it doesn't pull it all the way in.

 

[jcoop1]

Will do when I get back to the tractor this afternoon, thank you for the suggestion.

John