While on the subject of runaways, there is something that has been
missed....I am telling this from memory, not the manual, so, while the
principle is correct, the numbers may not be exact.
The military multifuel engine is governed to 2800 RPM (could be 2600, again
this is from memory), ASSUMING the governor is working correctly, the
injection pump will not pump enough fuel to blow the engine up, REGARDLESS of
the throttle setting. In fact, either the injector or engine manual tell you
top operate the engine at full throttle with no load for so many minutes as
part of the break in procedure.
Now, if the governor section of the injection pump has failed, you can blow
the engine up, even if the throttle works properly, simply by mashing the gas
too far.
As some one else has already mentioned, the most likely way to blow the
engine up is by introducing fuel from a source OTHER than the injection pump.
Crankcase oil is the most likely source of this outside fuel. When faced
with this situation there is NOTHING you can do to the fuel system to shut
the engine down, as the fuel causing the runaway is not going through the
injection pump or any other part of the fuel system. The only practical way
to shut it down is shut off the air. (you MAY be able to choke the truck
down by putting it in high gear, high range and releasing the clutch) One
way to shut off the air is by slapping a board over the air intake(s),
another way is to discharge a 15 pound CO2 fire extinguisher into the air
intake. The key under either method is that the engine MUST completely stop
revolving. If you run out of CO2 before it quits turning, or move the board
it will start all over again.
Hope this helps,
David
This archive was generated by hypermail 2b29 : Wed Apr 04 2001 - 08:10:49 PDT