Powder like substance in gas tank?

[jimmy77]

I just picked up a 1963 3hp. evinrude lightwin 3302s @ auction.
I was told it was started. and there was some gas in tank.
Well they must have been smokin somting cause it would only fire with gumout sprayed in cylinders and replacing plugs.
The good news is it did fire this way.
Next day started complete teardown. The filter in the gas tank was plugged. It had this whitish powder on it and the threads seamed to have it too.
The tank has this on the inside walls as well.
The gas line was plugged and after cleaning this it was on to the carb. Well it was ugly. The bowl had a green tint to it. and most everything was plugged. The carb only has one needle and the knob stated LEAN- RICH with arrows. NO bottom needle, just a threaded plug with washer.
Carb kit with float is on order.
Questions....
Can anyone tell me how to clean tank and what is this stuff?
Why is my serial # have a "S" on the end of #'s.
That's it for now. Will work my way down the motor.

Thanks for any help in this.
JIMMY77

[boats.net]

The powder is from the ethenol fuel, not sure what causes it. There are tank cleaners that are designed to breakdown the gunk/sludge. (startron tank cleaner) "S" usually stands for short shaft.

[jimmy77]

Thanks for the reply. Next ? gas tank filter?

Thanks for the lead on the startron tank cleaner. Got some shipped in and soaking the tank right now. I also tore down the carb and had the same green mess. After soaking parts, it's looks almost new. Even the slow speed needle that was green crusty to the tip looks like new.
Now the next thing I added to the soak tank was the stove top in tank filter. More of the green stuff. Soaking now. The questions is why is there such a fine bra ss filter then at the bottom of it there is a 2 sided 1/8 in. hole at the base where all the crap would sink to. AS of now I plan to add a inline filter besides reusing the original.
PS. the on-off valve is bent. Can I find replacement in hardware store?
Thanks again for all the knowledge.
jimmy77

[boats.net]

If it is the inline shut off valve, yes you can purchase one from a hardware store.