The Ford Barn

Maclab58 · 02-27-2014, 05:51 PM

My 31 slant window cabriolet has a nasty carb issue. If I don't cut the fuel off when I park it, it will drip fuel on the floor. Even with the GAV turned off it runs rich, when I pull up to a stop light if I don't turn up the throttle lever it will die. I am assuming that the float is set too high or the float valve is not closing all the way. Suggestions?

jthomas6 · 02-27-2014, 05:58 PM

Maclab58,

I had the same problem last summer with my '28 roadster. I replaced the float valve with one of the new ones, and shimmed to bring it to specs on the float level. Problem solved.

Joe

jm29henry · 02-27-2014, 06:23 PM

I agree with jthomas6 if the float is not set correctly even after you close, the shut off there is still fuel in the line and will drain, if the float is set to high the remaining fuel will drain into the fuel bowl. Also note that if the shut off under the dash is weeping this can add to your problem !

TinCup · 02-27-2014, 07:01 PM

I am sure some will agree and some will disagree but I have found that the newer rubber tipped Viton float valves really help with this. There are many resources for the correct float height I would make sure you check this as well. I would also check the GAV driver and make sure it is seating properly.

Maclab58 · 02-27-2014, 07:29 PM

I have purchased a "kit" that Brattons sells but I also bought the better float valve. Should I just do it all?

flatford39 · 02-27-2014, 08:34 PM

Sponsored Links (Register now to hide all advertisements)

Do it all is the answer. It is not that hard.

TinCup · 02-27-2014, 10:12 PM

Hey bring it to OKC for our next club meeting in March if you can wait. We have several really good carb guys and a bunch of hacks like me that can offer up some help. We have several members from the Lawton area. Always welcome.

johnbuckley · 02-28-2014, 04:50 AM

And here's the hit list.....
( in your case with the over-rich running it's likely to be #1,2,3,4 or 5)
Zeniths:Causes of leaking
Problem: Remedy
1 Leaking/loose float valve gasket: Tighten/reseal/replace
2 Leaking float valve: Replace
3 Friction on float hinge: Loosen
4 Incorrectly set fuel level: Re-set
5 Hole in float: Repair or replace
6 Cap jet or Main jet too short/ more than one gaskets on main jet: check
7 Leaking/loose gasket at main jet: Tighten/reseal/ replace
8 Leaking /loose gasket at cap jet: Tighten/replace
9 Leaking or loose GAV housing threads: Tighten/ reseal/ replace
10 Leak at fuel inlet union: Tighten/reseal/replace
11 Loose/leaking gasket at strainer: Tighten/reseal/replace
12 Loose/leaking gasket at drain plug: Tighten/reseal/replace
13 Cracked housing/leaking passage plugs: Repair or replace

1-6 will generally manifest as poor running.
7-13 will generally not affect running unless there is excessive leaking

rollingsculpture · 02-28-2014, 08:22 AM

nice list john a real saver for the notebook! thanks

02-27-2014, 05:58 PM	#2
jthomas6 Senior Member Join Date: May 2013 Location: E Tn. Posts: 169	Re: Zenith help Maclab58, I had the same problem last summer with my '28 roadster. I replaced the float valve with one of the new ones, and shimmed to bring it to specs on the float level. Problem solved. Joe

02-27-2014, 06:23 PM	#3
jm29henry Senior Member Join Date: Sep 2010 Location: michigan Posts: 1,126	Re: Zenith help I agree with jthomas6 if the float is not set correctly even after you close, the shut off there is still fuel in the line and will drain, if the float is set to high the remaining fuel will drain into the fuel bowl. Also note that if the shut off under the dash is weeping this can add to your problem !

02-27-2014, 07:01 PM	#4
TinCup Senior Member Join Date: May 2010 Location: OKC / Tonkawa, Ok. Posts: 1,977	Re: Zenith help I am sure some will agree and some will disagree but I have found that the newer rubber tipped Viton float valves really help with this. There are many resources for the correct float height I would make sure you check this as well. I would also check the GAV driver and make sure it is seating properly. __________________ Oklahoma City Model A Restorers Group.

02-27-2014, 07:29 PM	#5
Maclab58 Senior Member Join Date: Jul 2010 Location: Wichita Falls, Texas Posts: 983	Re: Zenith help I have purchased a "kit" that Brattons sells but I also bought the better float valve. Should I just do it all?

02-27-2014, 08:34 PM	#6
flatford39 Senior Member Join Date: May 2010 Location: NE Illinois Posts: 499	Re: Zenith help Sponsored Links (Register now to hide all advertisements) Do it all is the answer. It is not that hard.

02-27-2014, 05:51 PM	#1
Maclab58 Senior Member Join Date: Jul 2010 Location: Wichita Falls, Texas Posts: 983	Zenith help My 31 slant window cabriolet has a nasty carb issue. If I don't cut the fuel off when I park it, it will drip fuel on the floor. Even with the GAV turned off it runs rich, when I pull up to a stop light if I don't turn up the throttle lever it will die. I am assuming that the float is set too high or the float valve is not closing all the way. Suggestions?

02-27-2014, 10:12 PM	#7
TinCup Senior Member Join Date: May 2010 Location: OKC / Tonkawa, Ok. Posts: 1,977	Re: Zenith help Hey bring it to OKC for our next club meeting in March if you can wait. We have several really good carb guys and a bunch of hacks like me that can offer up some help. We have several members from the Lawton area. Always welcome. __________________ Oklahoma City Model A Restorers Group.

02-28-2014, 04:50 AM	#8
johnbuckley Senior Member Join Date: Jul 2010 Location: United Kingdom Posts: 1,442	Re: Zenith help And here's the hit list..... ( in your case with the over-rich running it's likely to be #1,2,3,4 or 5) Zeniths:Causes of leaking Problem: Remedy 1 Leaking/loose float valve gasket: Tighten/reseal/replace 2 Leaking float valve: Replace 3 Friction on float hinge: Loosen 4 Incorrectly set fuel level: Re-set 5 Hole in float: Repair or replace 6 Cap jet or Main jet too short/ more than one gaskets on main jet: check 7 Leaking/loose gasket at main jet: Tighten/reseal/ replace 8 Leaking /loose gasket at cap jet: Tighten/replace 9 Leaking or loose GAV housing threads: Tighten/ reseal/ replace 10 Leak at fuel inlet union: Tighten/reseal/replace 11 Loose/leaking gasket at strainer: Tighten/reseal/replace 12 Loose/leaking gasket at drain plug: Tighten/reseal/replace 13 Cracked housing/leaking passage plugs: Repair or replace 1-6 will generally manifest as poor running. 7-13 will generally not affect running unless there is excessive leaking Last edited by johnbuckley; 02-28-2014 at 05:38 AM.

02-28-2014, 08:22 AM	#9
rollingsculpture Senior Member Join Date: May 2010 Location: Takoma park md Posts: 271	Re: Zenith help nice list john a real saver for the notebook! thanks __________________ Rust and roll will never die