loose carb air filter cannisters

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Henry Ramirez
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loose carb air filter cannisters

#1 Post by Henry Ramirez »

Hello everyone, 356 Carb Rescue did a great job on my 64C carb rebuild but my Knecht air filter cannisters are loose enough to spin even when I've cinched them down. They also seem to be riding on the body of the carbs and could start wearing a groove in them. Not least, when I remove them I can see some oilly black residue on the outside body of the carb which seems to be dripping from the cannister. Is something missing? Thanks, Henry

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Dirk Heinrich
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#2 Post by Dirk Heinrich »

Hi Henry -

I think they are supposed to have a rubber ring where they mount to the flange of the Zenith.
You do need to fix it, because it can chafe through the carb top and you might get a fuel leak - that actually did happen to me last year!

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Henry Ramirez
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#3 Post by Henry Ramirez »

Thanks Dirk, did you get the rubber o-rings from a Registry vendor? Henry

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Dirk Heinrich
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#4 Post by Dirk Heinrich »

Henry, I don't think so. This is your man to ask:

John Jenkins at
619 224-3566

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Vic Skirmants
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#5 Post by Vic Skirmants »

Before everybody else runs out to check their air cleaners, only the C used the rubber O-rings.

Dick Weiss
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C air filter 'cans'

#6 Post by Dick Weiss »

Going further; the O-ring fits into a lip inside the extended neck to seal the top of the Zenith carb.

Dick

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Henry Ramirez
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#7 Post by Henry Ramirez »

Thanks Dirk, I'll give John a call. Vick, looking up into the cannisters I can see the raceway where the rubber ring would fit. Thanks, Henry

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Jim Fleming
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Loose air cleaners

#8 Post by Jim Fleming »

Henry,

What I have done on all my air cleaner canisters to tighten them up is cut straps (shims) out of galvanized steel sheet to go between the housing base and clamp. The clamps get stretched and distorted over the years so they don't grip the carb top any more. Some strategically placed flat washers can help the clamp bolt work better also.

The later C air cleaner canisters are very desirable because they have the detail (with o-ring) that extends into the carb throat so the condensed fuel that collects inside the air cleaner element will drain down inside of the carb instead of all over the top of it making a mess. The only problem with these air cleaner canisters is that they are taller and don't fit in the engine compartment of Speedsters, D's and Roadsters.

For my 1959 D I fabricated funnels out of sheet steel (from tin cans) that I slide down in the air cleaner throat to divert condensed fuel into the carb. These funnels also trap a rubber seal that works like the C air cleaner seal.
James H. Fleming

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Jim Fleming
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Zenith carb sealing funnels

#9 Post by Jim Fleming »

By popular request here is a mod I did 35 years ago to my conv'D to clean up the carb tops. I don't want to hear a bunch of grumbling from the rocket science nit pickers about flow bench data and fit tolerances. This is just a shade tree mod that worked for me.

Image


Image
James H. Fleming

tony apcar
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O ring

#10 Post by tony apcar »

Sorry Vic..works on A and B cars too any hardware store sells 50 cent O rings tony apcar.
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anthony apcar

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Larry Coreth
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#11 Post by Larry Coreth »

Jim,
Good drawing, even my drafting instructor from college would have approved. He was the one who threatened to flunk me if I didn't learn to letter properly ! With the advent of AutoCad this has become a lost art.
You are right it is doubtful that you will gain significant Hp from your “racing mod” but I would bet that it flows better than the original square step over the O ring ! I like it, simple, efficient, approaching elegant.
Larry Coreth
Roanoake Rapids, NC

Thomas Frisardi
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Re: loose carb air filter cannisters

#12 Post by Thomas Frisardi »

Follow up question. Is there a source for the complete clamp to secure the filter housing on the carburetor?

Dick Weiss
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Re: loose carb air filter cannisters

#13 Post by Dick Weiss »

It's amazing how many Zenith air filter cans @ the recent Stoddard swap meet don't have the proper clamps w/them.
I've made them over the years w/the proper shape and hardware --including the square nut.
Screw clamps don't work and they nlook bad!

Dick

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John Brooks
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Re: loose carb air filter cannisters

#14 Post by John Brooks »

Also I'd they are loose, they sit down on the carb top. This and vibrations will wear a groove in the left carburator top where the fuel line attaches. This will eventually lead to a non repairable fuel leak. If you are lucky.
John Brooks

62 Roadster
66 912
84 Cab
getting pushed around in porsches since 1965

Dick Weiss
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Re: loose carb air filter cannisters

#15 Post by Dick Weiss »

I've restored several carb top castings w/JB Weld; Also, I add/make special bronze threaded inserts to repair
the banjo bolt threads-- I don't use Helicoils. I have several repaired Zenith carb tops available for exchange.

Dick

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