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Pre-Mix Ratio

Stunty69

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HI,
My SL2000 has had the pre-mix unit removed so I need to add direct to fuel.
I have had a couple of 'suggestions' as to the ratio, does anyone have a definitive/correct one?

Any suggestions as to what is the best fuel and 2 stroke oil?

(Last time I used 2 stroke oil was 34 years ago, and on a small moped where cooking oil worked!)

Thank you....
 

4x15mph

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Speedling

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40:1 if you're running premix.
50:1 is safe if everything is 100% perfect, but 40:1 gives you a little leeway in case fuel isn't in the lines when you are first cranking. I HIGHLY suggest a primer of some sort if you don't already have one!!!
 

Speedling

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Speedling

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I can tell you that Steve wasn't a fan of premix. Upgrading the lines is a better solution. If you have your boat sit for say, a week, and the fuel runs back into the tank, which it does, then you are cranking on the engine with NO OIL IN IT!!!! Premix causes you to do this every time!!! This is why I stress a primer of some sort. I linked a great site for all sorts of wonderful information that you can use.
I highly suggest getting new impellers, and possibly even plastic wear rings. I had my exciter bumping 65 mph with just a few mods. It's insane!
 

treeskier

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Welcome.

I too am running oil injection and typically use the west marine oil and stock up when it is on sale. I have heard that some the pre-mixers use some type of synthetic oil that smokes less...less smoke...not smokeless. I was also advised away from premix since with the oil injection (and upgraded oil lines) much less oil is used at slow speeds and idle where it uses much more at speed...which is how the engines were designed to be run. That being said I know many successfully run the premix.
 

DCB-270

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Speedling

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The pump is giving more oil at lower rpms and less at upper.
He's at the premix point anyways.
80:1 is too lean.
again I suggest a primer or pump if premix.
 

treeskier

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itsdgm

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Welcome aboard @Stunty69. Sounds like the guys have given you the info on mix ratios that you were looking for. Just be very careful not to run out of fuel while you're running with pre-mix.
 

Yamatuf

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I always use Maxima Super M at 50:1 ratio. I have been running for 7 years with premix and no issues. If I can't mix it properly, shame on me. My oil lines popped off when I first bought the boat and cost me a complete rebuild.

I just bought a 5 gallon bucket for $173 on Amazon - expensive but worth it.

http://www.maximausa.com/product/super-m/
 
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