Suzuki 2 Strokes

Problem is with a 71 T350R, which has a plastic oil tank.

Was having trouble with air in the oil lines. Noticed air in the line where it connects to the oil tank.
Disconnected oil line at oil pump & it took something like 2 hours to drain 2/3 full oil tank.
Flushed tank with alcohol & there is some black crud in the bottom of the tank.

So it looks like the tank was draining too slowly & air was being sucked it where the oil line connects to the tank.

Question: how should I flush out the tank to get the crud out?

The inlet oil line is made in two parts: a rigid section near the pump & flexible part near the tank.
I separated the two sections without damaging the rigid section.
It now looks like this: Question: what should I use to replace the flexible line?

Also, some of the crud from the tank might be in the oil pump. So I'm going to disassemble & clean up the oil pump.

Ordered 3/16" yellow Tygon tubing. http://www.mcmaster.com/#catalog/119/123/=me2tyf
ID of original tube is closer to 5/32" but they don't sell that size.

Any suggestion of which type of crimp clamp is the best for the oil lines?
http://www.mcmaster.com/#pinch-clamps/=me2zk5

I use plain old nylon zip ties. Cheap, neat and tidy. I use them on all non pressure lines including fuel.

Problem solved.

Bought a used oil tank off of eBay. Used the yellow Tygon tubing & two of the stock clamps that Suzuki used at the oil tank.
Rebuilt the pump with new oil seals & o-rings.
Primed lines between pump & motor with red oil.

Have no bubbles & it didn't take much running for the red to turn to blue.