Another intake leak thread?

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kansasplowboy
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Another intake leak thread?

#1

Post by kansasplowboy »

Been working on my 59 pan w/stock Linkert. Have suspected an intake leak as my idle speed seems to just be slowly increasing all the time. Pulled the carb, built a pressure testing plate, applied 12-15 psi, and ..... nothing. Everythng seems to be nice and tight no bubbles. When I first start the pan (cold) it seems to be really rich, and as it warms up the mixture gets better. Could it be that the intake starts leaking as things get warmer? I am running the settings on the rich side just because in the past I suspected the intake leak. What am I missing?
Cotten
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Re: Another intake leak thread?

#2

Post by Cotten »

kansasplowboy!

Did you also test each pan cover screw over each port?
(A relatively rare event when they leak, yet still too common.)

Carburetor and manifold gasket flanges are prone to warpage.
Since this interface cannot be bubble-tested, then we must turn to the questionable un-lit propane torch trick, and test the top and bottom throttle bushings while you ar at it.

(Disclaimer: Please keep a fire extinguisher handy, and I don't mean just an open beer.)

Myself, I arbitrarily grind both flanges flat, (and the 'phenolic' or Micarta spacer as well), as they are invariably distorted from bolt stress.
Replacing bushings should be religious, as that is the only way to prevent the disc from wearing into the bore.

And of course, all gaps get bigger with heat.

Please adjust your lowspeed needle to where the machine likes it best, producing a quick idle. Trim the idle speed as necessary, but avoid a lopeing, slow idle, as it not only makes off-idle tuneing difficult, it is hard on the motor, and the carb itself.
An arbitrarily rich setting upon the lowspeed is an arbitrarily lean setting upon the highspeed.

...Cotten
kansasplowboy
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Re: Another intake leak thread?

#3

Post by kansasplowboy »

Cotten, thanks for the reply. I haven't checked the pan cover screws but I will. I keep reading about your floats and am interested in getting one how do I go about doing that? I really appreciate your response and advice. I'll keep you posted.
kansasplowboy
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Re: Another intake leak thread?

#4

Post by kansasplowboy »

No leaks at the pan cover screws. Trued up the carb flange and will try doing the propane test.
Cotten
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Re: Another intake leak thread?

#5

Post by Cotten »

kansasplowboy!

Please post me directly at liberty@npoint.net for float info.

Thanks,


....Cotten
Huck
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Re: Another intake leak thread?

#6

Post by Huck »

Viton o rings
James JGI-27060-55-V
Where do you find them, ordered a set on-line, after waiting a week I inquired where they might be and he returned my money. wth? A better pratice would have been letting me know he didn't have any. Anybody have a source, or better yet you deal for James? Let me know.
Regards
RussW
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Re: Another intake leak thread?

#7

Post by RussW »

I bought them here:
http://www.itwtrading.com/carb-intake.html" onclick="window.open(this.href);return false;
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