Author Topic: Leaky float bowls, not float height or gasket related.  (Read 1956 times)

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Offline GroovieGhoulie

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Leaky float bowls, not float height or gasket related.
« on: September 12, 2016, 06:51:56 PM »
So I'm flummoxed.  I haven't rode my 750 that much this summer (heat) and I went to go ride it a few weeks ago and the float bowls were leaking around the gaskets.  I was prepared for this, since the bowls leaked from the gaskets when it came out of long-term storage last year, but at that time, the old gaskets must've swelled up overnight from the fresh gas on them because when I ordered new gaskets and went to check them, it was dry and tight.

So I went with it and it's been fine for about 9 months.  I've had the new gaskets in the wrap, and since it's doing it again, I figured it's time to put them on and forget worrying about the old ones sealing or having to swell or whatever.

Well, I replaced all 4 gaskets, no pinching or crud in the groove or anything and #3 bowl still leaks pretty bad and #4 seeps pretty good.  It appears to be coming out of the bowl/body joint where the gasket is, but they are all new!  Not a drop is coming out of the overflow tubes, (and it starts seeping soon after turning the petcock, before the bowl would be full), so I don't think it's float-height, and with new gaskets, they should be holding tight.

So what could be causing this?  Do the new ones need to "swell up" too?

DH

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Re: Leaky float bowls, not float height or gasket related.
« Reply #1 on: September 12, 2016, 07:00:35 PM »
Is it hard to resnap the bowl clips? If so, keep repositioning the bowls till they snap without a lot of extra work. They are not seating completely.
I went thru this last year, even got an extra carb body in case it happens again.

Offline GroovieGhoulie

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Re: Leaky float bowls, not float height or gasket related.
« Reply #2 on: September 12, 2016, 07:04:51 PM »
Oddly enough, 3 IS hard to snap on and off.  I thought that was ok, since it clearly meant it was "sealing extra good", lol.  I'll go fiddle with it.  4 wasn't bad, but I'll mess with it too.

Offline harisuluv

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Re: Leaky float bowls, not float height or gasket related.
« Reply #3 on: September 12, 2016, 07:15:46 PM »
Probably leaking orings at the fuel T's.  Comes from the same just a little above, and therefore looks like it's coming from the float bowl.

DH

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Re: Leaky float bowls, not float height or gasket related.
« Reply #4 on: September 12, 2016, 07:17:39 PM »
I can't pretend what exactly fixed mine, but after dicking around with it for a LONG time, and many attempts, it quit leaking
and I could only attribute it to te bowl not seating properly for some reason. I thought there was a crack in the bowl or carb body.
Only clue it gave was when the bowl clip snapped in easier, like the others. once that happened, the bowl stopped leaking.
If the bowl leaks, the level will go down, and the float is constantly trying to maintain level, so the process continues till the leak is sealed.

DH

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Re: Leaky float bowls, not float height or gasket related.
« Reply #5 on: September 12, 2016, 07:24:16 PM »
Probably leaking orings at the fuel T's.  Comes from the same just a little above, and therefore looks like it's coming from the float bowl.


Yup, another possibility. My particular case was weird. And I had changed those rings in my "quest". Drove me nuts.

Offline harisuluv

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Re: Leaky float bowls, not float height or gasket related.
« Reply #6 on: September 12, 2016, 07:26:10 PM »
Regardless what the bowl gasket problem is, the float valve isn't sealing correctly sounds like.  Shouldn't be getting that high in the first place, unless you got it on the side stand or something.

Offline carnivorous chicken

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Re: Leaky float bowls, not float height or gasket related.
« Reply #7 on: September 12, 2016, 07:47:15 PM »
Regardless what the bowl gasket problem is, the float valve isn't sealing correctly sounds like.  Shouldn't be getting that high in the first place, unless you got it on the side stand or something.

Second that. Float bowl gaskets or O-rings are really only to prevent the occasional sloshing around from riding to spill over (or angled on the sidestand). Fuel shouldn't be coming out when it's flat and you turn the petcock on.

Offline DaveBarbier

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Re: Leaky float bowls, not float height or gasket related.
« Reply #8 on: September 13, 2016, 07:27:44 AM »
I don't have a 750 but I have a CL200 that uses clamps to close the bowls. I remember it leaking a lot because I swapped bowls accidentally. They didn't seat right until I moved them back to their original carb body.

I'm sure the bowls aren't matched to the body they're in from the factory, but with my CL there was enough variation that it caused a leak.

Offline madmtnmotors

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Re: Leaky float bowls, not float height or gasket related.
« Reply #9 on: September 13, 2016, 07:39:01 AM »
It starts seeping soon after turning the petcock, before the bowl would be full.

O-rings at the fuel rail crossover tubes.
TAMTF...


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