Author Topic: LeMans 3 - leaky carb  (Read 801 times)

Offline Vince in Milwaukee

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LeMans 3 - leaky carb
« on: June 10, 2019, 05:12:17 PM »
Looking for some help for a leaky carburetor on my LM3.  Installed a new float needle and seat (this has fixed the problem in past years), but it still leaks gas, although not as badly.  Tips / advice most appreciated as we've finally got some nice riding weather here in Wisconsin.   
1984 Moto Guzzi 850 LeMans III, 1986 California II
Gone but not forgotten:
1969 Moto Guzzi Ambo, 1994 BMW K75RTw/ABS, 1996 BMW R1100RT, and 1993 BMW K75

Online Chuck in Indiana

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Re: LeMans 3 - leaky carb
« Reply #1 on: June 10, 2019, 05:19:40 PM »
Float height set properly?
Chuck in (Elwood) Indiana/sometimes SoCal
 
87 AeroLario
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Offline Guzzidad

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Re: LeMans 3 - leaky carb
« Reply #2 on: June 10, 2019, 06:38:49 PM »
   What Chuck said. I just had to replace 2 floats because they filled with gas.

Online sdcr

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Re: LeMans 3 - leaky carb
« Reply #3 on: June 10, 2019, 07:07:45 PM »
Over the years, I've had to renew the float bowl nut gasket a few times.
John
2000 BMW R1100 RS
1983 BMW R100
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Re: LeMans 3 - leaky carb
« Reply #3 on: June 10, 2019, 07:07:45 PM »

Offline guzzista

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Re: LeMans 3 - leaky carb
« Reply #4 on: June 10, 2019, 07:30:57 PM »
Other places I have had leaks . 1: banjo fitting.  The 6mm fiber  washer  can  allow leakage if not replaced. I like to add a  aluminum washer  as well on the outside of the aforementioned washer , particularly on the left side carb where the access is  more limited and the view not as good. 2.  The bowl O ring even if this may be a no brainer to seasoned guzzisti. The recent ones I have come across seem to harden sooner due to ethanol fuel. Combined  with  a squished bowl nut washer, makes leakage more likely.

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1975 750S Tribute bike, 1994 Cali 1100, 2007 Ducati GT1000, 1983 SP1000, 1973 V7Sport project, 2017 California1400 Touring

Offline wirespokes

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Re: LeMans 3 - leaky carb
« Reply #5 on: June 10, 2019, 08:54:22 PM »
That pretty well covers it except for the fuel line. They tend to age right at the point where they attach. Snipping off a quarter or half an inch usually fixes.

Offline SED

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Re: LeMans 3 - leaky carb
« Reply #6 on: June 10, 2019, 11:32:42 PM »
Check that the float is not hanging up on the pivot or its supports.  I installed new plastic floats and one started to hang up after a few months.  Trimming the edge of the float pivot solved it.
1983 LeMans III
1981 Monza
1947 Ariel Red Hunter
1939 Ariel Red Hunter
1937 Guzzi GTV

 

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