emergency fuel shutoff valve question

[ZiggyO]

Hello all,

Quick question--- the 800 series 5-tons all have an emergency manual fuel shutoff valve on the injection pump with a dash mounted handle while the 915’s lack that feature. If I were to eliminate the valve all together (due to a bad seal in the valve causing air to get sucked into the fuel line for instance), would that be a particularly bad idea? Is the nhc250 more prone to runaway that the ntc400?


Ziggy

 

[Floridianson]

Don't think it would suck as that line has as much as 172lb of pressure. Now it might leak fuel.

 

[WillWagner]

You wouldn't have hard starting, erratic idle issues if that failed, you'd have a GIANT mess!

 

[davidkroberts]

i use mine as a anti-theft device anyway. Who would think to look under the hood and reset the switch.....

I havent heard of a runaway problem with the NTC but as soon as you pull the emergency switch......well they had to have put that switch in it for a reason. They even put it in the middle of the dash so you can grab it when your freaking out. Somebody thought it was a good idea.

 

[73m819]

I think it is more for if there is a battery or alt. problem, you would turn in the manual fuel control screw on the back of the fuel shut off solenoid to turn the fuel on then slave or pull/push start the truck, use the emg. shut off to shut it down

Or if the fuel shut off solenoid takes a crap, the screw is turned in to run, the emg. used for shut down

 

[motomacguyver]

I thought that a runaway diesel was when the truck leaks enough motor oil through the piston rings and valve train that it continues to run WITHOUT any added fuel. The only way to stop this was to block the air intake. (I have heard the Detroit Diesel 2 strokes were notorious for this.) In this instance the fuel shut off would not work.

 

[KsM715]

Correct, if the motor is getting fuel from somewhere other than the IP, that shut off valve wont do squat.

as far as the OP, If it were mine I wouldnt remove it, I would fix it.

 

[Hammer]

I took mine off. Shaft was bent, and I haven't found a replacement yet.
I WILL replace mine, when I can find a suitable replacement.
Until then, I just made a bypass pipe and run it.

 

[WillWagner]

It's a Cummins part...P/N 208087. Don't know if it is still a good number, but I can check price and availability tomorrow.

 

[ZiggyO]

Hello again,


In my case, the truck will run very rough and almost stall if the valve is not in a certain "sweet spot" (about 1/8-1/4 closed)-- if I push it all the way open, I get the running/idling issues-- hence the reason I though it may have been sucking air (but if the fuel is under pressure at that point, there must then be some other issue with the valve)....... If that part number comes back as available, please post it so I can order a replcement.........


thanks

Ziggy

 

[Floridianson]

I might guess that some how you valve is over riding and your not closing it but realy just opening it all the way.?

 

[area52]

I got one from Boyce in Utah, forget how much it was but they had it on the shelf.

 

[M817]

Emergency Fuel Shutt off

I replaced the Cummins fuel shut off, and it works fine now, however the brass nut is leaking on the emergency shutt off, is it possible to just order that brass fitting? searched the internet and didn't find it. It was sucking in air and causing my 5 ton to lack power and idle funny... any suggestions

 

[RicheyOne]

I believe I have a similar issue with the fuel solenoid. It will start and run fine, and even start up after a short trip. However after I shut it off, after a long trip (25+ miles) it will turn over all day and will not crank. I called a road service and the technician said it was absolutely a bad injector pump so I left it over night. Once I returned in the morning, as the wrecker pulled up I stepped into the truck and it fired right up...Got it home, tried to restart and same thing.

 

[73m819]

Could also be the PCB, this controls power to about everything, try over riding the fuel shut off valve and use the emg shut down to shut own, you might add a spring to the emg. lever so it will reset itself.