dieseling engine when shut down

[slomo]

Let it run to cool down, I have the same problem when the weather is hot. Just let it idle and cool down.

Here's another one. Maybe yours is water cooled with a full pressure lube oil pump??

 

[StarTech]

Remember guys, we had a problem with fuel causing vapor conditions. It turned out to be that the fuel suppliers didn't change from winter to summer soon enough. The fuel actually was boiling in the carbs and fuel line due to normal engine heat. This of course is not related to the current problem.

 

[Auto Doc's]

Idling down produces LESS air flow to cool the engine.

Also not recommended by any engine manufacturer to do this. All state to run at max revs all the time for max cooling, lubrication and longevity.

Hi slomo,

High airflow is especially important running under loaded conditions.

However, I have to disagree. An engine should not be shut down at full throttle. Rpm should be reduced to reduce the excess heat that has built up while under load. The engine still has more than sufficient air flow at lower RPM with no load.

This cool down idle period does not take very long, but it does reduce after-fire/backfire and run on dieseling problems. This especially important in gas engines that may have excessive carbon deposits on the head or top of the piston because they act like burning embers at higher RPM's.

 

[ILENGINE]

However, I have to disagree. An engine should not be shut down at full throttle. Rpm should be reduced to reduce the excess heat that has built up while under load. The engine still has more than sufficient air flow at lower RPM with no load.

This cool down idle period does not take very long, but it does reduce after-fire/backfire and run on dieseling problems. This especially important in gas engines that may have excessive carbon deposits on the head or top of the piston because they act like burning embers at higher RPM's.

True except Kohler/Rehlko. Kohler specs their carbs to were the idle circuit isn't controlled by the anti-afterfire solenoid, therefore Kohler recommends shutting their engines off at full throttle. Since the idle circuit isn't controlled by the fuel solenoid idling down before shutoff can actually cause the backfire to be more likely.