Turn off using choke?

J

Jack99

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North Ontario
Got a 2 stroke 1999 Yamaha 600 triple (with only 5,200 kms) and was doing some Google searches about different brands of Injector oils. Stumbled upon a few posts advising folks that if they plan to turn their sled's engine off for 8+ hours, they should `choke out` their engine. Then, turn off / remove its ignition key. This choking will flood the engine's inner chamber / piston cylinder chamber with extra gas (that contains oil) and it's better for the engine. Especially during cold Start Up the next morning / days.

Is this a good idea - especially for my older age engine?
 
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I choke out every single engine I can on shut down. Sled, leaf blower, lawnmower, weed wacker. It leaves ??xx amount of fuel & oil(if 2 stroke) in the combustion chamber upon start up. Helps w/ the carbon build-up as well.
 
Doing more thinking about this....

If using pre-mix engine (like my 50:1 boat engine or weed eater) and I give it full choke to kill its engine, its getting lots more gas. And if it gets gas,I know its getting lots more oil amount with the gas delivery as well. For pre-mix system, getting more oil amount before shut down is probably a good thing (good method to kill its engine).

If using factory injection system (like in my Yamaha sled) and I give it full choke to kill its engine, its getting much more gas. But if its engine RPM is the same amount (at idle RPM), its gets the same amount of oil (from its oil injection pump). And in the end, its getting more gas amount compared to its oil injection amount. Thus, its injected oil amount is being "diluted" at shut down. And, it washes the thin oil film off its cylinder walls. This is probably a bad method to kill its engine.

Please explain why using the choke on a 2-stoke factory Oil Injection system adds more oil amount (re: thicker oil ratio) using choke method.

For my factory oil injected sled, would it be better to simply raise its rear on a stand, increase its engine RPM to safely spin its track (gotta clean snow out of it anyway) and while holding its throttle at 1/8 position, simply turn its ignition key off? Thus, forcing its oil injection pump to pump more oil (compared to idle RPM amount) into its inner engine? And, it would eliminate the dilution of its oil amount ratio using its choke at rpm idle speed.

Which is the better shut down method for Yamaha factory Oil Injected sleds?


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its not that it get a richer oil to gas ratio, the oil is mixed with the fuel in the fuel pump in the mixing well then pumped to the carbs, by using the choke to shut off the engine at days end is for when its really cold out. It requires way less effort to start it in the morning as it will already be "primed" with a extra amount of fuel. The choke simply adds extra already mixed with oil fuel to the engine via the choke circuit and is in excess to the fuel provided by the pilot jet.
 
Jack99 said:
Doing more thinking about this....

If using pre-mix engine (like my 50:1 boat engine or weed eater) and I give it full choke to kill its engine, its getting lots more gas. And if it gets gas,I know its getting lots more oil amount with the gas delivery as well. For pre-mix system, getting more oil amount before shut down is probably a good thing (good method to kill its engine).

If using factory injection system (like in my Yamaha sled) and I give it full choke to kill its engine, its getting much more gas. But if its engine RPM is the same amount (at idle RPM), its gets the same amount of oil (from its oil injection pump). And in the end, its getting more gas amount compared to its oil injection amount. Thus, its injected oil amount is being "diluted" at shut down. And, it washes the thin oil film off its cylinder walls. This is probably a bad method to kill its engine.

Please explain why using the choke on a 2-stoke factory Oil Injection system adds more oil amount (re: thicker oil ratio) using choke method.

For my factory oil injected sled, would it be better to simply raise its rear on a stand, increase its engine RPM to safely spin its track (gotta clean snow out of it anyway) and while holding its throttle at 1/8 position, simply turn its ignition key off? Thus, forcing its oil injection pump to pump more oil (compared to idle RPM amount) into its inner engine? And, it would eliminate the dilution of its oil amount ratio using its choke at rpm idle speed.

Which is the better shut down method for Yamaha factory Oil Injected sleds?


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Click to expand...

You are seriously over thinking and over complicating this......
 
Over thinking? Not really. I live with an attitude of "do no harm". re: Validate before doing. I'm sure you do the same for your gathered tips / traps as well.

IMO, shutting down a factory Oil Injection system by diluting its oil amount ratio using choke at idle isn't a good thing to do... Pre-Mix = good thing to do.

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mrviper700 said:
its not that it get a richer oil to gas ratio, the oil is mixed with the fuel in the fuel pump in the mixing well then pumped to the carbs, by using the choke to shut off the engine at days end is for when its really cold out. It requires way less effort to start it in the morning as it will already be "primed" with a extra amount of fuel. The choke simply adds extra already mixed with oil fuel to the engine via the choke circuit and is in excess to the fuel provided by the pilot jet.
Click to expand...

Question... On these carbs, are the Oil Injection lines going to the carb's bowl container or are they connected on the intake side of the carb - bypassing the bowl?
 
As already stated, your oil is mixed with fuel in your fuel pump before it ever gets to your carbs.. At no time are you leaning out your oil vs fuel ratio by using your choke.
 
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