dieseling engine when shut down

[Johner]

Hello, i have a 16LTH Simplicity with a Briggs Vanguard engine...303777 0122-01 5526 90041811. The fuel shut off was bad so i replaced with an electric inline one. When engine is hot it don t want to stop, found on internet what i had But 170.00 in cost and that`s to much. the inline one takes awhile to shut off.....a lot of fuel inline valve to carb...the only thing i can do if put a switch on dash to shut valve off and wait for engine to die..............is there a better way thanks for reading

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

 

[RevB]

Hello, i have a 16LTH Simplicity with a Briggs Vanguard engine...303777 0122-01 5526 90041811. The fuel shut off was bad so i replaced with an electric inline one. When engine is hot it don t want to stop, found on internet what i had But 170.00 in cost and that`s to much. the inline one takes awhile to shut off.....a lot of fuel inline valve to carb...the only thing i can do if put a switch on dash to shut valve off and wait for engine to die..............is there a better way thanks for reading

I'm at a loss about your "fuel shut off" . Is this the carburetor solenoid or a manual valve? The solenoid is only $16 or less from plenty of sources and there isn't any $170 fuel parts anywhere on this engine.

 

[ILENGINE]

I'm at a loss about your "fuel shut off" . Is this the carburetor solenoid or a manual valve? The solenoid is only $16 or less from plenty of sources and there isn't any $170 fuel parts anywhere on this engine.

Fuel solenoid on this carb is https://www.partstree.com/parts/briggs-stratton-806472/. And I suspect the shutoff the OP was referring to is a electric inline fuel shutoff similar to this https://www.amazon.com/s?k=electric...5&ref=nb_sb_ss_p13n-expert-pd-ops-ranker_1_17

 

[bentrim]

I admit I did NOT read all the posts but hope I can add to the discussion.
The antifire solenoid mounted in the carburetor stops fuel flow thru the main jet, it does not stop flow to the carburetor the needle and seat do that.
If an inline fuel shut off is used whether manual or electric, the engne will not stop until the carburetor is empty, this may also result in engine run on, unless the ignition is killed 1st.
With the carburetor mounted antifire solenoid. the manufactures recommend to shut the engine down at 3/4 to full throttle. Why? as the engine winds down mainly air is pumped thru the engine and into the muffler. This is supposed to pump the fuel out of the muffler so you dong get that BANG. Even if the ignition kills the spark, which should be killed when the switch is shut off.

From the Kohler command opperators manual:

Stopping
1. Remove the load by disengaging all PTO driven
attachments.
2. For Carbureted Engines Without A Shutdown
Solenoid: Move the throttle to the slow or low
idle position. Allow the engine to run at idle for
30-60 seconds; then stop the engine.
For Carbureted Engines Equipped With A
Shutdown Solenoid: Position the throttle control
somewhere between half and full throttle; then
stop the engine.
For EFI Engines: Move the throttle to the slow or
idle position; turn key off to stop engine.

 

[jviews12]

I agree, fuel valve as close to carb as reasonable. let it run dry. have a cvlean and empty carb which does not plug up.

 

[Skippydiesel]

FACT:

An engine will not continue to run if:

• The fuel supply is cut off
• The ignition (in a spark ignition engines) is grounded
• Its not receiving sufficient O2 (air) to support combustion (not usually used to stop an engine)

Should a spark ignition engine continue to run after ignition turned off, it must be;

• Dieseling/spontaneous combustion, due to the continued supply of fuel. Investigate overheating/carbon build up.
• Ignition not actually off/grounded. Investigate switch action/terminal condition, ignition kill wires for continuity (broken) or not making contact.
• Fuel not off & spark ignition not off. Investigate fuel shut of system (if fitted) AND ignition kill system (above).

How hard can it be?

 

[StarTech]

• Fuel not off & spark ignition not off. Investigate fuel shut of system (if fitted) AND ignition kill system (above).

Hmmm that's a new one. An engine that runs on natural air only that doesn't have a fuel system.


Come on the mower was setup shut the carb fuel solenoid blocking the main jet, starving the engine of the fuel. I worked mowers with such a setup. They do need a backup system and get one installed at my place.

 

[Skippydiesel]

Hmmm that's a new one. An engine that runs on natural air only that doesn't have a fuel system.


Come on the mower was setup shut the carb fuel solenoid blocking the main jet, starving the engine of the fuel. I worked mowers with such a setup. They do need a backup system and get one installed at my place.

I think you misread/understood what I wrote.

• Fuel not off & spark ignition not off.

In this case :

The ignition wont turn off (kill circuit inoperative)
AND
The fuel wont turn off

Engine keeps running despite operator thinking kill circuit (switch/button/lever position) activated.

• Investigate fuel shut of system (if fitted) AND ignition kill system (above).

Investigate reasons why - suggested focus points.

 

[StarTech]

I understand what you getting at but these engine still has to have a fuel system of some kind fitted to even give problems and you said Investigate fuel shut of system (if fitted). Key words if fitted. but of we got read of as off. Correct wording is necessary; hence, the edit radio button.

That is what I was poling fun at.

The op has disabled the fuel solenoid by removing it or clipping it. And the ignition kill is not either working or not even present. What the op was calling dieseling was that now it has run until the carburetor fuel bowl is empty.

We basically told to either repair or install the ignition circuit or replace the carburetor fuel solenoid that he removed.

Geesh, I am not a hand holding person even in person.

 

[slomo]

Try letting the engine idle for a minute to cool down before you turn it off.

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.