Gasoline smell from carburetor

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vwlover77
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Location: North Canton, Ohio
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Gasoline smell from carburetor

Post by vwlover77 » Sun Mar 03, 2013 8:50 am

I finally figured out why my '71 Beetle with the 34 PICT 3 carb always smelled of gasoline after driving. The carb gaskets at the top and the base are wicking gasoline to their outside edges!

I bought a carb rebuild kit with new gaskets. Would applying Permatex aviation sealant to the new gaskets a few days prior to assembly be a good or bad idea? Can this stuff withstand gasoline?
Don

---------------------------
78 Westy
71 Super Beetle Convertible Autostick

"When we let our compassion go, we let go of whatever claim we have to the divine." - Bruce Springsteen

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Amskeptic
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Re: Gasoline smell from carburetor

Post by Amskeptic » Sun Mar 03, 2013 10:29 am

vwlover77 wrote:I finally figured out why my '71 Beetle with the 34 PICT 3 carb always smelled of gasoline after driving. The carb gaskets at the top and the base are wicking gasoline to their outside edges!

I bought a carb rebuild kit with new gaskets. Would applying Permatex aviation sealant to the new gaskets a few days prior to assembly be a good or bad idea? Can this stuff withstand gasoline?
Totally bad idea. There are holes in these gaskets, calibrated orifices on some cases. A fresh gasket with a light application of grease gently worked into the fibers is perfect.

This weeping is a perfectly normal consequence of people who refuse to check the tightness of the screws every blue moon or so.
Colin

(I would not necessarily declare that the fuel smell is because of gas weep at the gaskets, keep us posted on any recurrance)
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

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vwlover77
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Location: North Canton, Ohio
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Re: Gasoline smell from carburetor

Post by vwlover77 » Thu May 08, 2014 4:20 am

Further investigation showed that the intake manifold boots (the orange ones) apparently became porous over the few years they were installed and gas was migrating its way through them. That's all I can figure as the clamps were all tight. Also, the driver's side manifold gasket at the head showed signs of gas having leaked out around it.

I have now replaced the intake manifold boots and the manifold gaskets and have noticed a HUGE reduction in gas smell.
Don

---------------------------
78 Westy
71 Super Beetle Convertible Autostick

"When we let our compassion go, we let go of whatever claim we have to the divine." - Bruce Springsteen

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Amskeptic
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Re: Gasoline smell from carburetor

Post by Amskeptic » Thu May 08, 2014 8:55 am

vwlover77 wrote:Further investigation showed that the intake manifold boots (the orange ones) apparently became porous over the few years they were installed and gas was migrating its way through them. That's all I can figure as the clamps were all tight. Also, the driver's side manifold gasket at the head showed signs of gas having leaked out around it.

I have now replaced the intake manifold boots and the manifold gaskets and have noticed a HUGE reduction in gas smell.
Ethanol deterioration?
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

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asiab3
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Location: San Diego, CA
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Re: Gasoline smell from carburetor

Post by asiab3 » Thu May 08, 2014 8:48 pm

Amskeptic wrote:
vwlover77 wrote:…intake manifold boots (the orange ones) apparently became porous over the few years they were installed and gas was migrating its way through them.

I have now replaced the intake manifold boots and the manifold gaskets and have noticed a HUGE reduction in gas smell.
Ethanol deterioration?
Colin
My two most recent pairs both leaked after 7-8 months. Adrian @ Headflow Masters told me to try some special Gates 1.5" hose that was a beast to get on, but is holding up nicely. I'll report more formally after a year of use.
1969 bus, "Buddy."
100k miles with me.
279k miles on Earth.

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Amskeptic
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Re: Gasoline smell from carburetor

Post by Amskeptic » Fri May 09, 2014 6:50 am

asiab3 wrote:
Amskeptic wrote:
vwlover77 wrote:…intake manifold boots (the orange ones) apparently became porous over the few years they were installed and gas was migrating its way through them.

I have now replaced the intake manifold boots and the manifold gaskets and have noticed a HUGE reduction in gas smell.
Ethanol deterioration?
Colin
My two most recent pairs both leaked after 7-8 months. Adrian @ Headflow Masters told me to try some special Gates 1.5" hose that was a beast to get on, but is holding up nicely. I'll report more formally after a year of use.
We should provide feedback to our vendors
ColinSure
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

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