Discolored fuel mix from fuel line on Lawn-Boy 10247 Duraforce

Because of fuel leaking from the carb on my Lawn-Boy 10247 with a Duraforce 2-cycle engine on September 3rd as a quick fix I installed a new fuel line and a 90 degree shut-off valve.

After installing these items fuel mix from May of this year was put back in the tank and the mower was used. Because of problems I'm having with it running at the faster speeds on September 16th, I removed the remainder of fuel mix from May and filled the tank with fresh fuel mix and mowed the lawn.

Yesterday, I pulled the fuel line off the carb to check the fuel flow. The shut-off valve was turned to off, so I wasn't expecting any fuel to come out of the fuel line but it did before I could get a container under it, just a little on to the deck and it was brown colored. Putting a container under the end of the hose and turning on the shut-off valve the fuel began to flow quickly, brownish at first but quickly turning clear (no longer brown). I'd say the flow is unobstructed as it was coming at maybe an ounce a second (give or take). Was the initial fuel that spilled out of the hose brown because it had discolored from sitting in the hose or something else? Should I be concerned about this?

What I think you got was old sediment in the bottom of the tank settling around the fuel outlet and it was the first to drain out. If your mower is stock, you have a sediment screen over the main jet in the carb, as well as a sediment screen in the gas tank, so no big chunks of sediment will reach the main jet.

Phototone said:

What I think you got was old sediment in the bottom of the tank settling around the fuel outlet and it was the first to drain out. If your mower is stock, you have a sediment screen over the main jet in the carb, as well as a sediment screen in the gas tank, so no big chunks of sediment will reach the main jet.

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Other than the spark plug, CDI, fuel hose and shut-off valve the mower is completely stock. I suppose that it could be sediment and now that it has the shut-off valve it's getting "caught" in the fuel line between the shut-off and the carb when I stop mowing.