Go Back   The Ford Barn > General Discussion > Model A (1928-31)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 08-24-2016, 10:31 PM   #1
Bob from Northport
Senior Member
 
Bob from Northport's Avatar
 
Join Date: May 2010
Location: 215 E. 6th Street Northport, Michigan 49670
Posts: 933
Default Carburetor question

What is it about the float level that creates the problem where a vehicle will stall when coming to a stop, then starts back easily and runs fine. We have a 30 sport coupe right now that runs and starts and idles great, but stalls coming to a stop.
__________________
Bob from Northport
Northport, Michigan
Bob from Northport is offline   Reply With Quote
Old 08-24-2016, 10:50 PM   #2
Dave Mellor NJ
Senior Member
 
Join Date: May 2010
Posts: 761
Default Re: Carburetor question

Common model a fault. The float pivots front to back,shutting off the needle valve when stopping. That's why it was changed to side to side on the Model B
Dave Mellor NJ is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 08-24-2016, 11:41 PM   #3
ian Simpson
Senior Member
 
Join Date: Apr 2014
Posts: 709
Default Re: Carburetor question

Use the hand throttle to rev up as you come to a stop. Idle down once you are stationary.
ian Simpson is offline   Reply With Quote
Old 08-24-2016, 11:46 PM   #4
Synchro909
Senior Member
 
Synchro909's Avatar
 
Join Date: Jun 2014
Location: Melbourne, Australia
Posts: 7,471
Default Re: Carburetor question

This is caused by your float level being wrong. Set it correctly and all will be well. Les Andrews' book gives simple directions.
__________________
I'm part of the only ever generation with an analogue childhood and a digital adulthood.
Synchro909 is offline   Reply With Quote
Old 08-25-2016, 12:04 AM   #5
J Franklin
Senior Member
 
J Franklin's Avatar
 
Join Date: May 2010
Location: Oregon
Posts: 5,946
Default Re: Carburetor question

If all is adjusted correctly the stall will only happen on panic or very hard stops. I think the cause is too much gas to the jet in the bowl. I think shutting the float valve would not stall the car unless it was shut for quite a long interval or the fuel was Very low in the bowl
J Franklin is offline   Reply With Quote
Old 08-25-2016, 12:30 AM   #6
RandyinUtah
Senior Member
 
Join Date: May 2010
Location: Ogden Utah
Posts: 242
Default Re: Carburetor question

Sponsored Links (Register now to hide all advertisements)
I have driving my Model A 35 years with a Zenith carb and do not experience the stalling on a hard stop. I believe having the correct float level is the reason for this.
RandyinUtah is offline   Reply With Quote
Old 08-25-2016, 05:50 AM   #7
Ed Saniewski
Senior Member
 
Ed Saniewski's Avatar
 
Join Date: May 2010
Location: Denville NJ
Posts: 964
Default Re: Carburetor question

Franklin, I have thought the same thing. The float closes the gas flow to the bowl, and I cannot believe you will use up all the gas in the bowl while decelerating to a stop.
__________________
Model A Ford Club of New Jersey
http://www.mafcnj.org

Model A Pick Up Owners and Enthusiasts
https://www.fordbarn.com/forum/group.php?groupid=5
Ed Saniewski is offline   Reply With Quote
Old 08-25-2016, 08:13 AM   #8
talwrench
Member
 
Join Date: Feb 2015
Location: Quakertown, PA
Posts: 73
Default Re: Carburetor question

MY 30 P/U has a rebuilt carb. Has run great for six months. This past weekend it started to stall at stop signs. Do I have the same problem with float heigth?
Was running great!!
talwrench is offline   Reply With Quote
Old 08-25-2016, 10:39 AM   #9
katy
Senior Member
 
katy's Avatar
 
Join Date: Jun 2015
Location: Red Deer, Alberta
Posts: 5,004
Default Re: Carburetor question

Quote:
MY 30 P/U has a rebuilt carb. Has run great for six months. This past weekend it started to stall at stop signs. Do I have the same problem with float heigth?
Try adjusting it down a little and see what happens.
__________________
If you don't hear a rumor by 10 AM, start one!.
Got my education out behind the barn!
katy is offline   Reply With Quote
Old 08-25-2016, 01:30 PM   #10
Brentwood Bob
Senior Member
 
Join Date: May 2010
Location: brentwood, ca
Posts: 4,214
Default Re: Carburetor question

The secondary well might be plugged. Would not hurt to pull the carb apart (Zenith) And check the idle circuit.
Brentwood Bob is offline   Reply With Quote
Old 08-25-2016, 04:02 PM   #11
Keith True
Senior Member
 
Keith True's Avatar
 
Join Date: May 2010
Location: Epping N.H.
Posts: 2,969
Default Re: Carburetor question

If the car was fine before I would lean toward the secondary well too.The float level doesn't change with use,unless something goes bad.If the little holes to feed the well get plugged when you stop fast the well empties and can't replenish fast enough to recover.Seems there can be a problem with the secondary well where the gas rushes up and floods a little,but I can't quite remember the particulars about having that problem.I've seen lots of people that took their carbs all apart,and cleaned them,but didn't take out the secondary well.I've had to drill quite a few of them out.Use a 3/8 drill,reverse spiral,and at some point during the drilling the well will spin itself out.
Keith True is offline   Reply With Quote
Old 08-25-2016, 05:49 PM   #12
Tom Endy
Senior Member
 
Tom Endy's Avatar
 
Join Date: May 2010
Location: Southern California
Posts: 3,122
Default Re: Carburetor question

A Model A Zenith carburetor by design should not stall at a stop. Five million Model A's were delivered new. I doubt they stalled at a stop when new.

Most Zeniths today have been molested in one way or the other over the years. If properly restored they will not stall at a stop. There are a lot of things to consider during the restoration process. The fitting of the throttle plate is as important as the proper float level to avoid stalling at a stop.

Secondary wells that are difficult to remove can easily be removed by heating the casting in the area of the well and dunking it in cold water. It will easily unscrew then.

Tom Endy
Tom Endy is offline   Reply With Quote
Old 08-29-2016, 11:23 PM   #13
Axeman71
Junior Member
 
Axeman71's Avatar
 
Join Date: Mar 2014
Location: Snohomish, Washington
Posts: 4
Default Re: Carburetor question

Quote:
Originally Posted by katy View Post
Try adjusting it down a little and see what happens.
Totally agree.. Float needs to come down
__________________
1928 Phaeton
Axeman71 is offline   Reply With Quote
Old 08-30-2016, 02:56 AM   #14
Synchro909
Senior Member
 
Synchro909's Avatar
 
Join Date: Jun 2014
Location: Melbourne, Australia
Posts: 7,471
Default Re: Carburetor question

Yup, a washer under the seat.
__________________
I'm part of the only ever generation with an analogue childhood and a digital adulthood.
Synchro909 is offline   Reply With Quote
Old 08-30-2016, 08:43 AM   #15
bogdonj
Senior Member
 
bogdonj's Avatar
 
Join Date: Aug 2010
Location: Walkerton, Ont. Canada
Posts: 623
Default Re: Carburetor question

Float needs to be adjusted to proper height or get in the habit of using the hand throttle when coming to a stop. Bring it down a notch or two until you have stopped then return it back to the up right position.
__________________
_________________________________________
1931 Ford Model A Tudor
1930 Ford Model A Deluxe Roadster
1930 Ford Original Rolling Chassis- Restoring
bogdonj is offline   Reply With Quote
Old 08-30-2016, 09:34 AM   #16
BILL WILLIAMSON
Senior Member
 
BILL WILLIAMSON's Avatar
 
Join Date: Dec 2010
Location: FRESNO, CA
Posts: 12,560
Default Re: Carburetor question

Henry Ford KNEW it was a poor design, that's why he CHANGED it.
In unpredictable stop & go traffic, I just set the hand throttle up, a couple of notches. Generally, the better the BRAKES, the more often the STALL--LOL
Bill W.
__________________
"THE ASSISTANT GURU OF STUFF"
BILL WILLIAMSON is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 03:51 AM.