1933 Model B GAV

[Randy in ca]

Nice original fordor just out of long term storage. The GAV is stuck - cable is OK and the choke works fine. Any tips to try to free it up without disassembling it from the carb? If removal is needed what's the procedure? Unlike the Model A's, the assembly is pressed into place rather than threaded. Also, which rotation direction opens and closes the valve - I seem to recall reading or hearing that it is the opposite of the Model A(?). Any insight appreciated.

[big job]

No idea what a stuck GAV is? got- A- V-8

[51 MERC-CT]

Originally Posted by big job

No idea what a stuck GAV is? got- A- V-8

Gas Adjusting Valve
As it applies to model A's---
http://www.model-a.org/gav_seat.html

[big job]

Thanks, must be a old age barrier, cause I do a Model A and T.....We call It fuel enrichment up here...

[Terry,OH]

Instructions for use of the GAV are in the Ford owners manual. A search here on the fordbarn.com will also come up with some results. I believe CCW is rich and open???? The linkage will come apart at the Carb and you should be able to then put a small adjustable wrench on the adjustment. May want to use some penetrating oil. Vince Falter has a web page devoted to the Model B Zenith Carb. lots of good info.

[51 MERC-CT]

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And a little anatomy

[jimTN]

If all else fails, remove carb. take base off and heat the cast iron red hot around the needle and seat, let cool and it will come out easily.

[Frank Miller]

Try spraying some carb cleaner in there. It is brass and if most likely gummed up with varnish. You'll probably have to disassemble the crb anyway if that's the problem.

[Randy in ca]

Originally Posted by Terry,OH

Instructions for use of the GAV are in the Ford owners manual......

Actually they aren't. Being as so few of these cars were produced apparently Ford did not produce a separate manual for the 33-34 Model B 4 cylinder cars. The original manual found in the glove box for this car was a V8 manual which tends to agree with this. Apparently the only owners manual Ford put out that covers anything for the 4 cylinder engines was that for commercial vehicle, trucks, etc.

All I could find concerning the GAV operation by searching (lots) old posts was were one person "thought" that the Model B used opposite threads than the Model A to open and close - if someone could confirm this it would be good to know before I try to free it up.

Also cannot find anything anywhere concerning the best way to remove the assembly, if indeed it comes down to that. Unlike the Model A which had the GAV assembly screwed in, the Model B assembly is pressed in place - tricky to remove without damaging and possibly tough to find a replacement.

I'm aware of Vince's site and have spent a lot of time there, but no answers to these questions that I could find. Actually the engine runs very well as everything now is, as long as it's warmed up a bit before heading out, but any further info anyone can provide on the operation and removal of the GAV would be appreciated. Thanks.

[petehoovie]

Nice car!....

[Doctor's Ford]

I restored the GAV of my 33 model B Zenith carburetor with parts provided by David Renner, at Renner's Corner, in Michigan. I spoke several times with David junior who specializes in model As and Bs carburators. Extremely helpful and knowledgable. Two years ago his father, David Sr, sent me a number of small parts that I ordered by phone and he said I could send him a check whenever I got the parts! Very honest people and I am sure will help you with this GAV issue which is exactly what he did for me. He has all those small parts for the GAV and the internals of the model B carburetors

The GAV is pressed in as stated. No thread. Suggest you first get the parts from Renner so if yours get damaged when pulling the old one is not going to be a big deal.

http://www.rennerscorner.com/ 1-734-428-8424

[qmdv]

I always thought the 33 and 34 were the Model C. The C crank is much better than the B.

Tim

[Charlie Stephens]

Originally Posted by qmdv

I always thought the 33 and 34 were the Model C. The C crank is much better than the B.

Tim

You and a lot of other people expected it would be called the Model C but Ford called it the Model B from '32 to '34. The "C" crank as you incorrectly called it came out in October 1932.

Charlie Stephens

[koates]

Randy, I have just rebuilt a 1932 B engine and fitted a new rebuild kit to the zenith carb. I have the sticking and jamming problem with the GAV which was also present before the carb rebuild kit was fitted. The brass needle valve has a right hand thread and as the choke knob is rotated clockwise the needle closes down on its seat and leans off the fuel mixture. This is the position the valve is left in once the engine is warmed up and you are driving. When starting the engine from cold and driving whilst cold the choke knob (and GAV) are rotated anti clockwise about half a turn or so to richen up the mixture. I don't know why the needle valve is jamming when it is closed off but suspect a problem down in the valve seat which cannot be seen. I tried to contact Dave Renner a few days ago but have had no luck with that yet. I have had both a reproduction needle and an original FORD script marked brass needle fitted and both tend to jam when closed off clockwise. Possible the GAV outer brass sleeve seat is worn or the cast part of the carb body. That brass sleeve is pressed into the carb casting and would be tricky to pull out. Some good illustrations and descriptions are shown in the FORD SERVICE BULLETIN for JUNE 1932 on pages 8 to 11 which is available in reprint form (red cover)as FORD SERVICE INSTRUCTIONS #32-66917-1 from MACS or other vendors for about $15.00. When I am able to speak to Renners I will post what I find out. Regards, Kevin.

[Terry,OH]

Randy: You are correct Ford did not publish an instruction manual for the 33 or 34 Ford 4 Cyl. They carried over the 32 copyright, 4 Cyl. manual.

[Bored&Stroked]

Neat thread guys - have never owned a 4 cyl car, but am still interested in learning. Thanks!

By the way, a really neat car. My first car was a 34 four door - drove it to high school in the 70's. I was the only guy with an early Ford - but I was sure proud to own one.

[Randy in ca]

Thanks for all the good info and comments. Kevin, curious how you make out with your's - good luck and keep us updated.

[koates]

Randy, I have just found amongst my many books a good book called CARBURETTORS, DYKE, which has an excellent clear sectioned view of the B carb. It shows a return spring and seating washer down underneath the GAV brass outer sleeve which seems to place some tension upwards on the GAV brass needle valve to maybe prevent it from locking up. If the original spring is damaged or rusted it my be the cause of the problem. I have an old carb which I will endeavour to remove the brass sleeve so I can have a look down in the bottom. Will try next week when I get a chance. Regards, Kevin.

[Doctor's Ford]

Randy. May be this photo will be helpful. These are all the components of the GAV system of model B zenith carburetor and in what order they are assembled. Part A is included in your choke cable. You can get them all from Dave Renner. Notice there is no thread on the bronze sleeve (part C). It has to remain tight where it seats so a bit of Loctite or similar glue is recommended when installing. That is why it is hard to remove. I believe the spring at the end pushes up to keep the needle free. May be your spring is rusted or broken and not working anymore?