Got a suction pump, but ask you knowledgeable members, what outer diameter of plastic pipe I would need, to reach down oil dipstick tube to the bottom of sump?

I tried a 11mm outer diameter, and that only went down (guessing) close to base of dipstick tube.

 

Is it a case of getting varying diameters of pipe, to reach the size I want ? 

 

Thanks in advance, for your help and assistance.

measure the width of the dipstick?

measure the width of the dipstick?

What a simple solution, never thought of that, would be a great start point.. at 6mm just measured.

Many thanks  'mobilone'

 

Quick update: Will accept outer diameter of 8mm, with 5mm inner diameter..