VST Spring Start-up Question?

[byron.akhavi@gmail.com]

I have a 2019 Yamaha F40LAoutboard. I winterized the engine with fresh gas and Yamaha Fogging oil mix (2 gallons non ethanol fuel). I ran the mix through and emptied the fuel filter cup before running the motor (to ensure the gas mix was in the cup). I did not drain the VST and hooked up the separate gas tank with mix. Ran the motor at fast idle for 25 minutes to ensure the mixed gas passed through the fuel system. The motor was run in a filled 55 gallon drum with constant water supply. I mixed Yamaha fuel stabilizer and Ringfree in the tank with the fogging gas mix.

My question is about the VST. Should I drain the VST and pump fresh non ethanol fuel into the fuel cup and VST before starting in the spring?? I always empty the fuel cup and install a new fuel filter in the spring. Then pump the fresh gas until the filter is full. Then I start the motor in the drum and run for 25 minutes. Afterwards, I install a new water pump kit and change the spark plugs cold. I just never drain that VST tank that has the mixed gas in it and let the new fuel cycle through. I was thinking about opening the lower drain screw and draining the VST along with the fuel filter cup. Then pump fresh gas in and fill the tank and cup before starting. Just do not know if this is a good idea since the engine has always started without issue the last three years.

Please forward your thoughts since you have much more experience than me regarding best practices. As always, I appreciate your assistance and comments.

[TownsendsFJR1300]

Draining old fuel and replacing with new is never a bad idea...

Might pump the primer too (with the VST drain open) , catch what comes out till fresh fuel shows and no crap.

.

[DennisG01]

Sure, it can't "hurt" to drain the VST. But it's not necessary - espeically considering the ****tail mix you used. That gas would still be good a year from now.

FYI... some other things that aren't "bad to do", but just a waste of time/money/landfill... replacing the filter every year, especially since you are using a drainable filter. Also, unless you run in shallow, sandy/dirty water - replacing the impeller is also not needed. Same with the plugs. I don't even replace plugs on 2-strokes every year - I inspect them, give light cleaning, and reuse. I replace when I start to see the slightest wear. I've been doing it this way wtih many different motors for decades.

That said, if you enjoy this and are OK with the time involvement/money/landfill thing - go for it! If it makes you feel better, that's all that matters.

I do drain a little bit out of the VST "just to be sure".

Oh... I've been using the same, non-drainable filter for about 5 years, now. I installed a vacuum gauge on the filter head to know when it's getting clogged. I hav eno issues with replacing things when needed, I just prefer not to do it (for the most part) "just because".

[TownsendsFJR1300]

I'll drain my VST after every 3rd or 4th outing.

Just to make sure there's no crap /water in there.

Non E fuel, RF and stabilizer as well as a see thru fuel filter...

With that said, I've never replaced the VST filter. It was apart once under warranty (was not the "low idle issue").

[byron.akhavi@gmail.com]

Thanks for the comments and reply everyone. I am going to leave the VST alone. I like the vacuum gauge test. Great idea!!

[DennisG01]

Your welcome, Byron! All I did was get a small vacuum gauge and screw it into the unused "output" port on my filter head (it stays screwed in there all the time). When I see that start to rise more than normal - time to change!