What might be causing this gas leak? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

DetroitIron · 02-09-2013, 07:04 PM

I am trying to get rid of this little gas pool on the manifold under the choke housing. Attaching pic. Checked most bolts and gas line. All good

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DetroitIron · 02-09-2013, 11:15 PM

Carb bolts are snug. Can't tell where the gas is leaking, but it's puddling under the choke housing. Any help?
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Duster · 02-09-2013, 11:53 PM

It looks like it is coming from that upper gasket. It is hard to tell from the picture. It looks like there is fuel on top of fuel inlet. I can't tell though.

If it is running good you almost don't want to mess with it.

dieseldawg142 · 02-10-2013, 01:46 AM

have you checked your accelerator pump diaphram? hard to tell but it looks like fuel on the bottom of the inlet leading back to a.pump

geezer#99 · 02-10-2013, 01:54 AM

Nothing wrong with the carb. It's coming from the bolt. It's crankcase vapour combined with a bit of oil. That bolt hole is open to the valley below the intake. If you use the wrong bolt or one with a lock washer and don't put some thread sealant on the bolt you'll get a little leakage there. THe bolt head needs to sit square on the intake. Most used a small flat washer like those used on exhaust manifold's.

DetroitIron · 02-10-2013, 09:08 AM

Thanks guys. I'll explore further based on feedback. The bolt leaking vapor is one I did not even consider....maybe remove bolt and apply thread sealant and retorq
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6 Door King · 02-10-2013, 04:25 PM

Most gas leaks in my truck are caused by poor sphincter control.

INSIDIOUS '86 · 02-10-2013, 05:51 PM

It is prob coming from the throttle shaft. They get worn easy since the springs and throttle pull it back. This is why the correct way is to have the springs pull the throttle forward and the throttle cable pulls back. = a lot less wear.

The only way you can fix it is. A. New carb. B. rebuild(recommended) c. Motor swap with a holley haha
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Duster · 02-10-2013, 08:16 PM

Quote:

Originally Posted by 6 door king

most gas leaks in my truck are caused by poor sphincter control.

ha!

THE "10" SILVERADO · 02-10-2013, 08:30 PM

Quote:

Originally Posted by 6 Door King

Most gas leaks in my truck are caused by poor sphincter control.

Wow, I'm going to have some sweet tea sticky keys on my keyboard for a while now....that was a good laugh though

motornut · 02-11-2013, 08:01 AM

Quote:

Originally Posted by INSIDIOUS '86

It is prob coming from the throttle shaft. They get worn easy since the springs and throttle pull it back. This is why the correct way is to have the springs pull the throttle forward and the throttle cable pulls back. = a lot less wear.

The only way you can fix it is. A. New carb. B. rebuild(recommended) c. Motor swap with a holley haha
Posted via Mobile Device

looks wet in the right place,for shaft wear
you would see it drip,out/off the end....

02-09-2013, 07:04 PM	#1
DetroitIron Registered User Join Date: Jul 2010 Location: Hudsonville, MI Posts: 174	What might be causing this gas leak? I am trying to get rid of this little gas pool on the manifold under the choke housing. Attaching pic. Checked most bolts and gas line. All good Posted via Mobile Device Posted via Mobile Device __________________ _______________________________________________ 1985 Chevy Scottsdale K20 350 with 700R4 running 3.42 gearing aka "The Honey Badger" 1993 Silverado C3500 Ext. Cab Dually 6.5 turbo diesel

02-09-2013, 11:15 PM	#2
DetroitIron Registered User Join Date: Jul 2010 Location: Hudsonville, MI Posts: 174	Re: What might be causing this gas leak? Carb bolts are snug. Can't tell where the gas is leaking, but it's puddling under the choke housing. Any help? Posted via Mobile Device __________________ _______________________________________________ 1985 Chevy Scottsdale K20 350 with 700R4 running 3.42 gearing aka "The Honey Badger" 1993 Silverado C3500 Ext. Cab Dually 6.5 turbo diesel

02-09-2013, 11:53 PM	#3
Duster Registered User Join Date: Feb 2013 Location: Ada, OK Posts: 117	Re: What might be causing this gas leak? It looks like it is coming from that upper gasket. It is hard to tell from the picture. It looks like there is fuel on top of fuel inlet. I can't tell though. If it is running good you almost don't want to mess with it.

02-10-2013, 01:46 AM	#4
dieseldawg142 Registered User Join Date: Jul 2011 Location: back 40, bc Posts: 3,906	Re: What might be causing this gas leak? have you checked your accelerator pump diaphram? hard to tell but it looks like fuel on the bottom of the inlet leading back to a.pump

02-10-2013, 01:54 AM	#5
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,736	Re: What might be causing this gas leak? Nothing wrong with the carb. It's coming from the bolt. It's crankcase vapour combined with a bit of oil. That bolt hole is open to the valley below the intake. If you use the wrong bolt or one with a lock washer and don't put some thread sealant on the bolt you'll get a little leakage there. THe bolt head needs to sit square on the intake. Most used a small flat washer like those used on exhaust manifold's.

02-10-2013, 09:08 AM	#6
DetroitIron Registered User Join Date: Jul 2010 Location: Hudsonville, MI Posts: 174	Re: What might be causing this gas leak? Thanks guys. I'll explore further based on feedback. The bolt leaking vapor is one I did not even consider....maybe remove bolt and apply thread sealant and retorq Posted via Mobile Device __________________ _______________________________________________ 1985 Chevy Scottsdale K20 350 with 700R4 running 3.42 gearing aka "The Honey Badger" 1993 Silverado C3500 Ext. Cab Dually 6.5 turbo diesel

02-10-2013, 04:25 PM	#7
6 Door King Registered User Join Date: Jun 2008 Location: Franklin Virginia Posts: 204	Re: What might be causing this gas leak? Most gas leaks in my truck are caused by poor sphincter control. __________________ 1954 3100 Nova Subframe, Pontiac Posi, roller for now1967 C-10 SWB 350/350/Posi. Soon to be Crew Cab! 1978 Crew Cab Dually roller 1982 C-30 Rollback, 454, 4 speed 2004 K1500 Suburban Z71 5.3 Kid Mover

02-10-2013, 05:51 PM	#8
INSIDIOUS '86 Registered User Join Date: Jul 2009 Location: washington Posts: 4,178	Re: What might be causing this gas leak? It is prob coming from the throttle shaft. They get worn easy since the springs and throttle pull it back. This is why the correct way is to have the springs pull the throttle forward and the throttle cable pulls back. = a lot less wear. The only way you can fix it is. A. New carb. B. rebuild(recommended) c. Motor swap with a holley haha Posted via Mobile Device __________________ 377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac 3''spintech prostreet mufflers xpipe 1 3/4 headers build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217 Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511



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