cummins 220 ??

[dadeo]

i noticed in your Crown Advisor, in the section- Engines- it says not to run the 220 engine out of fuel, that it would have disasterous effects.
My freind and I, weve been wondering; when you shut off the engine with the key... in a gasoline engine it shuts off the spark, and in a diesel engine I thought it shut off the fuel. If thats the case, isnt that the same, in effect, as running out of fuel??

[Sharkey]

Could be that that section of the web site could use a bit of updating, I was working from some information passed along from questionable sources.

Shutting off the "ignition" does stop the flow of fuel, but it does it by preventing fuel from entering the plunger section of the injection pump (on Bosch pumps, other engine shut off devices could simply spill any and all pressurized fuel without sending it out the delivery ports to the injectors. This is the way that the old Perkins non-electric injection pumps worked, and how the "stop" levers on Bosch and Mercedes pumps function). Running out of fuel allows the plunger to continue to pressurize fuel and/or air into the injection lines and into the injectors. It is then very difficult to purge the injection system of the air so that sufficient pressure can be generated to make the injectors spray fuel into the cylinders so that the engine will run (air will compress, while fuel will not). The problem from this is more a "getting it running" again problem than engine damage.

There is also an "emergency shut off" which is a gate valve in the fuel line running to the injection pump's inlet. It's reserved for the possibility of the stop solenoid freezing up, which would prevent you from shutting down the engine normally. Closing this valve could result in injection pump damage due to the high value of suction generated when the pump pulls agains the closed valve. There are specific warning about using this valve except in an emergency printed on decals in the engine compartment of my bus.

[dadeo]

cool, I think that answers my question. It just really sounds awful, the idea of the oil getting by the rings and running the engine to its death!! The newer engines are all computer controlled, and Ive even seen one in a kubota tractor thats "self priming" if you run it out. Perhaps all newer diesel engines are this way??