Author Topic: carb float bowl drains  (Read 1119 times)

Offline mattsz

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carb float bowl drains
« on: August 28, 2020, 09:57:27 PM »
Hi guys -

I've mounted my carbs to the bike just to fill them with fuel to see if all the bowls are filling and to check for leaks - yes, and none... so far.

Noob question: is opening the drain screws supposed to drain the fuel through the overflow hoses, or should the fuel just run out at the drain screws?  I'm guessing the latter (which mine are doing) is correct.  Sure would be nice and easy if the fuel drained out the hoses, much easier to collect!

Offline philward

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Re: carb float bowl drains
« Reply #1 on: August 28, 2020, 10:04:51 PM »
Its the latter so your carbs are draining as they should - couldn't drain out of overflow pipes as the brass overflow tube in the bowl is above the level of the fuel level in the bowls. Drain screws and overflow tubes are 2 different purposes.
Just thank your lucky stars the fuel isn't coming out of overflow tubes!
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Offline mattsz

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Re: carb float bowl drains
« Reply #2 on: August 28, 2020, 10:09:01 PM »
Thanks philward!  It's just too bad the drain screw openings don't somehow lead to the overflow hoses for ease of draining.  But then I guess if you find fuel coming out the hose(s), you don't know if it's an overflow problem or a drain problem...

I did find it challenging to connect the temporary fuel supply and get the fuel flowing with all of my fingers crossed!  ;D

Offline mattsz

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Re: carb float bowl drains
« Reply #3 on: August 28, 2020, 10:49:03 PM »
Anybody have a particular routine and/or piece(es) of equipment they use to quickly and easily drain the carbs?  I just had a terrible time using different size funnels and pieces of plastic bent into troughs to try to direct the fuel flow from the drains to a container - instead of it draining all over the crank cases...

Offline robvangulik

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Re: carb float bowl drains
« Reply #4 on: August 28, 2020, 11:39:09 PM »
I've got an indestructable glas teacup that fits nicely under the carbs, just large enough to hold the contents of 1 floatbowl :)

Offline mike the bike

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Re: carb float bowl drains
« Reply #5 on: August 28, 2020, 11:42:14 PM »
I run the engine with fuel off until it stalls, then a wodge of blue roll mops up what's left.
Where's that 10mm socket got to?

Offline mattsz

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Re: carb float bowl drains
« Reply #6 on: August 29, 2020, 12:11:35 AM »
Thanks guys!

Running it dry isn't bad - only I'm working on carbs without a running engine...

I'll dig around for something that fits in there...

Offline taysidedragon

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Re: carb float bowl drains
« Reply #7 on: August 29, 2020, 12:15:55 AM »
I got a petrol proof clear plastic bottle and cut the bottom off to make a shallow container that slides under the float bowl. Bit fiddly but works for me.
Gareth

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Offline H2Eric

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Re: carb float bowl drains
« Reply #8 on: August 29, 2020, 10:33:03 AM »
Use an aluminium foil tray from a pie. The bonus is that you get to eat the pie, before messing about with petrol that is.

Offline mattsz

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Re: carb float bowl drains
« Reply #9 on: August 29, 2020, 11:40:56 AM »
Mmmm, pie...

For the past six months, our local recycling center hasn't been accepting most household containers, due to Covid19 concerns.  I've got room in my basement, so I've just been stockpiling until they open back up again.  As a result, I've got a pretty wide and varied collection of containers - yogurt tubs, laundry detergent bottles, milk jugs - I'll paw through them and see if I can't find something I can cut down to size that will do...

Offline JezzaPeach

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Re: carb float bowl drains
« Reply #10 on: August 29, 2020, 12:10:03 PM »
Cut down Chinese takeaway container. Same benefit as buying a pie 😁
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Offline SteveD CB500K0

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Re: carb float bowl drains
« Reply #11 on: August 29, 2020, 12:18:42 PM »
Except that by the time you’ve finished cutting it down, you’re hungry again…


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Offline JezzaPeach

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Re: carb float bowl drains
« Reply #12 on: August 29, 2020, 01:07:44 PM »
😂 😂 😂
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from 1975-78. Garnet Brown.

Online ST1100

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Re: carb float bowl drains
« Reply #13 on: August 29, 2020, 01:28:06 PM »
STOC #637
'00 ST1100Y, '04 ST1100R, '07 NT700VA, CB500K2, CB500K1...

Offline mattsz

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Re: carb float bowl drains
« Reply #14 on: August 29, 2020, 04:14:14 PM »
I came home from a recent hospital stay with one of these plastic "kidney dishes" - don't worry, it's unused!  It's about 8 inches long; cut down in height to fit beneath the carbs, it could work well...

https://www.amazon.com/500cc-Kidney-Shaped-Emesis-Basin/dp/B00EDO0UJA


 

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