float level

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aussie gt
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float level

Post by aussie gt »

Hi guys, Have been off line for only five years (have had a few life problems). Dug 1973 GT750k out of back of shed to try to finish project. Having problems with float level, fuel leaks out of carbs at bowl gasket. set at 27mm.
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jabcb
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Re: float level

Post by jabcb »

Congrats on getting through life's problems & getting back to your Suzuki.

If the carbs start leaking after the bike has been sitting for some time like over night or a few days, then suspect a leaking petcock.

If one carb starts leaking rather quickly, then suspect a sunken float. I had this happen to a T500 that was fine before putting it away for the winter — fuel leaked badly out of one carb when I tried to start it in the spring.

A bit more info would help us come up with useful advice.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
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T350 69 & 71
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GTandcbr
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Re: float level

Post by GTandcbr »

How clean are the carbs ? If float needle valve has any debris in it it won't switch off fuel. Just checking that the Petcock is in on or reserve but not prime?
98 carb Blackbird and GT550j
aussie gt
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Re: float level

Post by aussie gt »

I checked float level of each carby on bench with no problems. needle & seat holds. But fitted to bike they leak. Carbys seem to tilt forward when on bike. Maybe needs float level lower
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Re: float level

Post by GTandcbr »

Hi
The fuel level is critical to the running and performance of the bike and it has to be set at the stipulated level or the bike will either run too rich or worse too lean. Just want to confirm that the float level was measured from the carb body and not the gasket and with the carb tilted at 45 degrees and the tang on the float just touching the extended spring part of the float needle valve?
98 carb Blackbird and GT550j
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jabcb
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Re: float level

Post by jabcb »

You can confirm the actual fuel level by using a fuel level tool.
https://www.z1enterprises.com/fuel-leve ... uzuki.html

Check the fuel level with the carbs horizontal. This shows the correct level on a GT250 carb:
Image
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
aussie gt
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Joined: Fri Sep 14, 2012 3:00 am
Country: Australia
Suzuki 2-Strokes: ts125, ts185, gt750k, gt750j
Location: central west, New South Wales

Re: float level

Post by aussie gt »

Thanks jabcb ,have used fuel level tool and same as your photo on bench but i am thinking when on bike it may different
Also thanks GTandcbr ,have set float levels the same as you described. But maybe i am out on measuring,
See the carby tilting forward .
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GTandcbr
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Re: float level

Post by GTandcbr »

Another thing to consider is warped float bowl rims. Over time the alloy becomes slightly warped and therefore doesn't seal properly. This can be sorted by rubbing the bowl on a piece of fine emery paper laid on a pane of glass and gently sand it level.
May be worth a try?
98 carb Blackbird and GT550j
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Re: float level

Post by sportston »

I seem to remember one guy on here recommends making your own viton rubber gaskets and finds that helps
aussie gt
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Re: float level

Post by aussie gt »

Removed float bowls and checked for warping. And they were warped, sanded as GTandcbr suggested. a lot better but still weeping .May need to replace gaskets. Good news the motor started for the first time after rebuild and stayed running without starting a fire (no fuel running across floor of shed) :D
GTandcbr
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Re: float level

Post by GTandcbr »

Result! Good news that the engine ran :D
98 carb Blackbird and GT550j
aussie gt
Around the block
Posts: 74
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Suzuki 2-Strokes: ts125, ts185, gt750k, gt750j
Location: central west, New South Wales

Re: float level

Post by aussie gt »

Thanks GTandcbr ,I have ordered new OME Suzuki gaskets from my local dealer ,still available. :up:
aussie gt
Around the block
Posts: 74
Joined: Fri Sep 14, 2012 3:00 am
Country: Australia
Suzuki 2-Strokes: ts125, ts185, gt750k, gt750j
Location: central west, New South Wales

Re: float level

Post by aussie gt »

Fitted new suzuki gaskets and all good now.
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Re: float level

Post by sportston »

excellent. glad you got it sorted
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