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Motorcycle Repair/How to Drain Gas Through Car Carb


Hello again. Thanks for answering my former question about draining the old gas from my 1973 Honda CB175K. Your answers are all excellent, the problem is I don't know exactly where the drain screw on the float bowl is under the carb. I see the hose part but don't want to do it that way. I've searched for pics of a carb that match my motorcycle but I can't find any that show the part you mention - they mostly show how to totally break down and rebuild a carb. This is probably annoying to you but is there any way you can explain to me where the screw is that I need to drain the gas?  In the area of the screw, are there other screws that I might think is the correct screw when it isn't?  I'm sorry for sounding so stupid but I really have to drain the gas and doing it thru the carb seems the easiest way and I am lost. I know that when I'm sure which screw to loosen I should loosen it just enough to have the gas start coming out and catch the gas in some type of container and when drained, retighten the screw. I'd appreciate your help again, I don't know where the float bowl is or what it even looks like. Thanks for your time. Arlene

Hi Arlene,

This should be a link to a picture of the carburetor
float bowl with the flat headed drain screw on it:

This is on the bottom side of the carb and should look
similar if it has a drain screw on the bowl.
Not all carbs have this but yours should I believe.

I just thought of another way I removed old fuel one time
not so long ago on a Honda 90.

Get a cheap gravy baster or large syringe and jam a piece
of gas line or hose in the end of it.
Draw the old gas out with this until the tank is empty.
It works good if you can get it leak proof.
They also make devices for siphoning fuel
out that you could get from an auto shop.
They consist of a hose and a suction bellows
with a one way valve so you can pump the fuel out.

Try to get as much fuel out as you can and then
look inside the tank with a flashlight to see
if it looks fairly clean.

Good luck with it.

Wayne S

Motorcycle Repair

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Wayne S.


Licensed Motorcycle Mechanic, Knowledge of motorcycles from 1960 up, Japanese, British and most other brand motorcycle repairs.


Worked for Yamaha, Honda, Suzuki, Kawasaki British: Triumph, Norton, BSA Other: Most Scooters and Mo-Peds

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