The Ford Barn

29er · 06-05-2013, 11:10 PM

Is there supposed to be a gasket under the brass GAV seat on the Zenith carb?

Thanks!

Benson · 06-05-2013, 11:18 PM

Quote:

Originally Posted by 29er

Is there supposed to be a gasket under the brass GAV seat on the Zenith carb?

Thanks!

Yes also it is a good idea, as in all jets, to check that the seat is not grooved or damaged. You do not want any leaks!

29er · 06-05-2013, 11:48 PM

Thanks Benson. Yes, we want no leaks! So, how's the best way to check the jet seats? Some of 'em are in pretty deep, dark holes!

Benson · 06-06-2013, 07:02 AM

A bright flash light and look for damage or pieces of old gaskets on the flat area where the gasket seats.

It is common to find 2 or 3 gaskets under the main jet ( drain plug in bottom of carb).

Folks remove the jet and the gasket sticks to casting, then they install another jet. Now there are too many gaskets and the jet is too low to operate correctly.

http://model-a.org/main_jet.html see below

Quote:
Note: The cap jet, located next to the main jet should be lower than the main jet. If not then there might be too many gaskets under the main jet.

"When installed with a washer, its tip should be level with the Lower Casting shelf that the Venturi sits on. So, when you remove a Main Jet, make sure you also dig out the old gasket. If you end up with multiple gaskets installed, it will cause poor performance and leaks, because the Jet tip isn't precisely where it should be in the Venturi.
Unquote

A word of caution: DO NOT hammer on a screwdriver to breakup the old gaskets!! Doing so will create a gouge in the gasket seat and ruin the casting!

Bert's Model A Center carb website written by Chris Pelikan is here:

http://model-a.org

29er · 06-06-2013, 10:16 AM

Sponsored Links (Register now to hide all advertisements)

Many thanks, Benson! Great help. I recently bought a spare Zenith carb to keep on the shelf and am rebuilding it for the learning experience. The site you posted is a wonderful resource, as is the search function on FB, which mentions a couple other references including Tom Endy's dissertation on restoring the Model A Zenith carb:

http://modelabasics.com/Carb/ZenithC...l2011-2007.pdf

Most appreciative of your help! I know this has all been asked and answered many times before, but we can keep these old cars running by the patience of you experienced, wise, gnarled-knuckled guys answering newbie questions!

Mike

06-05-2013, 11:10 PM	#1
29er Senior Member Join Date: Apr 2013 Location: Oregon Posts: 465	Carburetor Gasket Question Is there supposed to be a gasket under the brass GAV seat on the Zenith carb? Thanks!

06-05-2013, 11:48 PM	#3
29er Senior Member Join Date: Apr 2013 Location: Oregon Posts: 465	Re: Carburetor Gasket Question Thanks Benson. Yes, we want no leaks! So, how's the best way to check the jet seats? Some of 'em are in pretty deep, dark holes!

06-06-2013, 07:02 AM	#4
Benson Senior Member Join Date: May 2010 Posts: 2,594	Re: Carburetor Gasket Question A bright flash light and look for damage or pieces of old gaskets on the flat area where the gasket seats. It is common to find 2 or 3 gaskets under the main jet ( drain plug in bottom of carb). Folks remove the jet and the gasket sticks to casting, then they install another jet. Now there are too many gaskets and the jet is too low to operate correctly. http://model-a.org/main_jet.html see below Quote: Note: The cap jet, located next to the main jet should be lower than the main jet. If not then there might be too many gaskets under the main jet. "When installed with a washer, its tip should be level with the Lower Casting shelf that the Venturi sits on. So, when you remove a Main Jet, make sure you also dig out the old gasket. If you end up with multiple gaskets installed, it will cause poor performance and leaks, because the Jet tip isn't precisely where it should be in the Venturi. Unquote A word of caution: DO NOT hammer on a screwdriver to breakup the old gaskets!! Doing so will create a gouge in the gasket seat and ruin the casting! Bert's Model A Center carb website written by Chris Pelikan is here: http://model-a.org Last edited by Benson; 06-06-2013 at 07:38 AM.

06-06-2013, 10:16 AM	#5
29er Senior Member Join Date: Apr 2013 Location: Oregon Posts: 465	Re: Carburetor Gasket Question Sponsored Links (Register now to hide all advertisements) Many thanks, Benson! Great help. I recently bought a spare Zenith carb to keep on the shelf and am rebuilding it for the learning experience. The site you posted is a wonderful resource, as is the search function on FB, which mentions a couple other references including Tom Endy's dissertation on restoring the Model A Zenith carb: http://modelabasics.com/Carb/ZenithC...l2011-2007.pdf Most appreciative of your help! I know this has all been asked and answered many times before, but we can keep these old cars running by the patience of you experienced, wise, gnarled-knuckled guys answering newbie questions! Mike