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Leaking carburators

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PeeWee
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Joined: Sun Mar 16, 2014 8:26 am

Leaking carburators

Post by PeeWee »

In a attempt to start my restored R51/3 for the first time ,
I found both my carburators leaking at the idle screw when I opened the fuel cock .
What could be wrong ?
45533221-89BD-460D-B6AA-675160B2249E.jpeg

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schrader7032
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Re: Leaking carburators

Post by schrader7032 »

Are the floats rising up to seal the flow of fuel in the bowl? Could the floats be defective?
Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2
Fast. Neat. Average. Friendly. Good. Good.

PeeWee
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Re: Leaking carburators

Post by PeeWee »

I will check that, but they are new

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CWRoady
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Re: Leaking carburators

Post by CWRoady »

I had the same issue on my left carb after a rebuild and resolved by replacing the float needle that had a minimal imperfection. This might help.

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Chris
1955 R50 / 1973 R75/5 / 1974 R90/6 Hack / 2015 RT
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PeeWee
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Re: Leaking carburators

Post by PeeWee »

I’ve taken a look,at the artikel from Salis and must admit that the problem could lay in the fact that my bike was on the side stand .
My center stand isn’t there yet but In the coming weekend I will look at it , holding the bike straight .

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jwonder
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Re: Leaking carburators

Post by jwonder »

A few things.

1) They will always leak if you leave the petcock on, especially on the side stand.

2) I always turn the petcock off and let it run for a 1 minute at every stop, even for coffee. Just remember to turn it back on when you get back.

3) On occasion I have used a very light rubbing compound to seat the needle. Don't overdo it, just a little.

4) On the side stand they tend to leak, as you said, try the center stand.
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xackley
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Re: Leaking carburators

Post by xackley »

My ritual for side stand parking is

1 extend stand and lean the bike
2 shut off petcock
3 shut off light
4 get off bike
5 take a moment
6 pull the key.

99% chance the carb won't over flow through the mixture screw.

On a cold start when on the side stand I hold down the right primer button longer than the left.

Don

Edit just noticed you said both carbs were leaking.

Tooth paste on float needle
Spin needle on seat.
1958 R69, 1972 R75/5, 1980 XS650, 1982 GL1100, 2003 guzzi ev, 2017 guzzi V7!!!
All on the road, going no where in particular in the Finger Lakes of New York

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