I have recently changed to a truck where I found out accidentally that the engine on/off switch actually works on the remote box.So tell me this,what is the purpose besides the obvious?,and it seems stopping and starting the engine while in PTO would cause undo strain on driveline/stiebel box/engine?Of all the units I have operated the engine on/off feature has been disabled so please educate me.

If I'm on the 6th floor and looking down at the pump with hydraulic fluid bleeding out, I like the engine kill option.  I haven't had to use it, but it's nice knowing it's there.

Not sure about the reason why the option was invented, I would guess it has to do with Europe.  Over there I understand that they turn the engine off to conserve fuel if the mud truck isn't there.  If you're smart, you'll disable it on everyone's truck in your fleet.  Too many people use it for the fun of it, and don't understand that the chattering on the clutch gear inside the pto will round out the teeth.  Another big problem with the option is that there is no low air safety to the start up.  In otherwords, if air pressure gets too low, nothing is holding that clutch gear in position except that little rinky-dink ball held up by the spring.  It's a sure fire way to pull up to a job, put it in pto, rev up the motor, and hear those gears grind.  Now you're in neutral.

im like you guys im not exactly sure what it was invented for but ive been 5 floors up pouring through 400 ft of system (light weight) having to pour slow get plugged and the truck stall out. ive never had to use it besides that but man i was glad that i had it then.

 That's a safety feature, Much more effective than the "E stop". I was up on a bridge deck and looked down at the pump and the cab was full of white smoke, I was lucky to be able to shut it down on the remote. It's a good feature to have. But I agree, only for emergency use. I've seen plenty of guys use it, even mechanics, but it sure sounds bad when you shut em down? Starting it with the remote does'nt sound as bad.

 On some remote boxes the engine on/off switch is right next to the throttle switch. It's very easy to hit the starter switch when trying to throttle up. This probably causes more damage than stopping and starting combined.

I use it all the time...to save fuel and to get some peace and quiet around the worksite...and even if the air pressaure drops while engine off, never will it grind the teeth in pto gearbox. But if the engine is running for an hour whithout pumping, I think it´s better to turn it off. In sweden it´s common that you have to wait that long.

I use it quiet  often only on the merc trucks,they run a live drive no drop box so no rattle noises.Had the schwing 47 blow hyd hose that thing pumps 636ltrs a minute of hyd oil so it was good to shut it strait down.

If the 2 Big German manufactuer deliver a pump with that function and a Steibelbox why should You not use it ?

I operate the pump Niklas operate now for ower 7 year and use it daily and it still works....

i think that they should move the switch away from the throyyle switch, and make a guard over  it to prevent accidentally hitting it and killing the motor

 Some of the older german pumps mounted on mercs used a merc gearbox pto instead of a transfer box. This is held in by air pressure and when that is lost so is the drive, When the air builds back up again the pto tries to engage on its own with eventually not pleasant results! 

Also by using the stop start  the ignition and everthing turned on in the cab(heater, lights , radio , pump electrics etc) is still running, it dont take long on a cold winters day for you to be left in the brown and smelly!!!!

I've noticed that most operators think that if it doesn't break when you do it once, then it's not bad for the equipment, and you  can do it all the time.  I promise you guys that you're wearing out that sliding clutch on the pto side, and it will eventually fail.  There's no telling when it'll fail, but it will sometime.  It's like the sliding clutch in the hi/lo in the tranny, if you don't preload it just one time, the damage is done.  It may take a year from that point to completely round off the gear, but it will fail.  And to what you said Vasa about the manufacturers put it on so it must not be bad.  If you're friends with people in those operations, many of them will tell you privately to disable it because it will ruin the pto.

By the way, I'm speaking about using it in America.  Obviously, if it's standard to turn the pump off in between trucks because of the price of fuel in Europe, I understand that the switch will be used over there.  The damage isn't as bad because you're not waiting for that long, presumably, before the next truck gets there.  I disable it because guys will just turn the truck off and an hour or two later turn it on, that's when the real damage occurs.

Used on european spec trucks like mercedes, MAN. The PTO there are different to your US version transfer box. They are direct drive from rear of engine. Different rate of wear and tear on startup on or off - very minimal and PTO's use double clutch packs. Air leaks cause problems if it falls below 6 bar, but you shouldn't have major air leak anyway (unroadworthy)

The truck engines there, especially turbos, are not designed to run at idle for prolonged periods of time as the cylinder bores tend to become glazed and would require rebuild.

The remote for my Putz will only shut the engine off. For some reason you can't start it from the remote box. I like that option for "just in case" situations. I do agree that having it right beside the throttle switch could have been planned a little differently though.