Cat 259b3 Fuel Won't Shut Off

[Inland1]

Machine keeps running at very low rpms after key is shut off. I figure it is the shut off solenoid failing but, could use any helpful info on changing or any other possibie problem. Thanks.

 

[OLDDODGETRUCKS]

To the top, My 259B3 YZ00721 has the exact same problem, any pointers for diagnosis? Machine runs fine but as soon as you turn off the key the rpms drop but it wont shut off. If you then go full throttle it will die.

 

[heymccall]

#4 is the stop solenoid. Same Delphi pump as my 420E backhoes.
There is a defect in the pump. I'm certain that there WAS a service letter on them.
One 420E works normal here, and the other does as you've described.
AFAIK, if changing the stop solenoid doesn't resolve the issue, the pump will need replaced. I've since put on over 5k hours on mine since the "diesel on" started, and it hasn't gotten worse. Still pissed at Cat dealer for not finding the service letter when I brought the problem to their attention.

 

[thepumpguysc]

That pic is a Bosch/Zexel VE pump.. not a Delphi.. & there is no SB about the solenoid on either that I'm aware of..

 

[heymccall]

Sorry, TPG...got my pumps mixed up.

The 420E was an SM, not an SL. Here
https://www.heavyequipmentforums.co...-running-after-turning-off.72254/#post-753421

 

[thepumpguysc]

Those "Latch Valves" are a real weak spot in the design..
Its because of emissions that was introduced.. It "reduces the amount of smoke" at start-up..

 

[heymccall]

Does the pump in the original post above possibly have the same malady?

 

[thepumpguysc]

without doing alot of searching.. the OP will have to tell me what pump he has..
Pics are always nice..
It goes along the lines of walking up to a parts counter & saying, I have a Ford Mustang & I need a part for the engine..

 

[heymccall]

336-9190 ($1800 from Caterpillar)

 

[OLDDODGETRUCKS]

my pump is a zexel/Bosch
010 Y265218
Pump number 104642-3050
Not sure how to post pics
There are 2 solenoids on my pump
-The solenoid on the top of my pump
352-3694 is a “cold start advance”.
-Deductive reasoning tells me The solenoid on the rear of my pump
335-5735 is the “shutoff solenoid”
I get +12v to the rear solenoid with key on and 0v with key off.
Bad solenoid?

 

[OLDDODGETRUCKS]

See attached pics of my pump

 

[thepumpguysc]

Yes, the sol. on the rear is the shut off sol.
I think the CS Sol. is on a timer..??

 

[OLDDODGETRUCKS]

Yes, the sol. on the rear is the shut off sol.
I think the CS Sol. is on a timer..??

Yes the shut off solenoid is bad? Can i remove the shut off solenoid on the machine without removing the pump?

 

[thepumpguysc]

What..?? U get 12v w/ the key on.. & 0v w/ it off is exactly how its supposed to work.. 12v= run.. 0v= stop.
Yes u can remove it on the engine. {open end wrench} U have to pull the boot back & remove the 8mm nut to get the wire out of the way..

 

[OLDDODGETRUCKS]

What..?? U get 12v w/ the key on.. & 0v w/ it off is exactly how its supposed to work.. 12v= run.. 0v= stop.
Yes u can remove it on the engine. {open end wrench} U have to pull the boot back & remove the 8mm nut to get the wire out of the way..

Removed the shut off solenoid and inspected, did not appear to be damaged or sticking in any way. Reinstalled it and the problem is much worse, have to bog down the aux hydraulics at full throttle to kill it now.... will try a new solenoid and report back.

 

[OLDDODGETRUCKS]

Removed the shut off solenoid and inspected, did not appear to be damaged or sticking in any way. Reinstalled it and the problem is much worse, have to bog down the aux hydraulics at full throttle to kill it now.... will try a new solenoid and report back.

Update:
Replaced the shut off solenoid, no change.

 

[thepumpguysc]

ODT.. contact me at my home email & I'll tell u how to fix it..
Just click on my screen name to the left & that'll get u to my contact info..

 

[OLDDODGETRUCKS]

UPDATE:
Removed injection pump and had it rebuilt, Pump shop couldn't find anything visually wrong during disassembly but it would not shut off on the test stand. They Replaced the "Head" in the injection pump and now it works fine.

 

[thepumpguysc]

Yes.. thats the fix if u dont know what yer doing..
They would have been able to adjust it on the test stand if they tried..
& THATS WHY the new H&R worked, they adjusted it on the T. Stand..
Hell, u could of done it but u never contacted me..
Live & Learn I guess.. Glad yer up & running..

 

[OLDDODGETRUCKS]

Yes.. thats the fix if u dont know what yer doing..
They would have been able to adjust it on the test stand if they tried..
& THATS WHY the new H&R worked, they adjusted it on the T. Stand..
Hell, u could of done it but u never contacted me..
Live & Learn I guess.. Glad yer up & running..

You caught me red handed i dont know what im doing when it comes to the internal function of these injection pumps. I did not see your post prior to having the pump rebuilt.
lived and learned... ROUND 2!!! i just bought another 259 site unseen today and after unloading it from the trailer same thing it wont shut off even with the power wire removed from the shut off solenoid on the pump.
So "thepumpguysc" please school us all on how to adjust the H&R ourselves if it is really possible?