"NY" wrote in message
o.uk...
"Harry Bloomfield" wrote in message
news
NY explained on 23/07/2018 :
How would the sump oil find its way into the cylinder? Via leaky piston
rings? I presume top gear and hard on footbrake *should* stall the
engine.

There are various ways for the engine oil to get into the combustion
chamber, there are numerous examples on Youtube of runaway diesel
engines. Some have even tried to use it as an excuse for speeding for
tens of miles. The footbrake certainly 'should' be able to stall the
engine, the engine will have much less power available than normal.

I've vague memories of something my dad told me long time ago. He was
first on the scene at a lorry accident (fortunately no-one was hurt) and
he tried to turn off the lorry's engine at the ignition key. It carried on
going. The driver told him to pull a lever somewhere and there was a lot
of hissing and spluttering and the engine gradually stopped. Now the
obvious thing that a lever would operate would be a fuel shutoff that was
independent of the solenoid that was kept open by the ignition switch, but
that doesn't match the hissing and spluttering. It make me wonder whether
some lorries had a means of venting the cylinders to the atmosphere as a
crude way of breaking the cycle and stalling the engine - maybe by holding
the exhaust valve open during the compression and power stroke to avoid
the compression ignition.

Was that ever done as a way of stalling an engine to turn it off. It would
have been in the late 60s, so whatever technology (mechanical fuel pump
and injectors) was around at the time. Not sure whether it was 2-stroke
(eg Commer "Knocker") or 4-stroke.

More likely it was a way of letting the engine be spun up with a less gung
ho battery by stopping the full compression until the engine was turning
over at a decent speed. In the days before compressed air engine starters
which are now almost universal on those big engines.