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How long is the smallest diameter hole in the jet? He was just pouring enough lead to cover the hole then drilling through it.
 

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Strange as is sounds, the jet is the component with a specific diameter hole in it, the needle which works with the jet is often mistakenly called a jet.

That said, there is no 'idle' jet in a Zenith carb, there is an air idle needle. There is a well vent jet, which you do not want to mess with, a discharge jet, and the main jet which controls the run fuel/air mix. That is the one at the bottom of the carb.

Check here to see if they have what you are looking for. Parts for Aluminum Zenith Carburetors

Roger,
 

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Discussion Starter #6
Strange as is sounds, the jet is the component with a specific diameter hole in it, the needle which works with the jet is often mistakenly called a jet.

That said, there is no 'idle' jet in a Zenith carb, there is an air idle needle. There is a well vent jet, which you do not want to mess with, a discharge jet, and the main jet which controls the run fuel/air mix. That is the one at the bottom of the carb.

Check here to see if they have what you are looking for. Parts for Aluminum Zenith Carburetors

Roger,
I beg to differ. Item 9 idle jet C55-6-12. That air idle needle affects the amount of fuel drawn through the idle jet. I can turn that needle out 5 turns and there is not effect on the idle quality. Now remember I am using this carb on a Frazer Rototiller that is a two stroke.
 

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Discussion Starter #7
How long is the smallest diameter hole in the jet? He was just pouring enough lead to cover the hole then drilling through it.
The jet is 1/2" long. Too small for my old eyes to try and modify. Surely someone out there has jets. I was in touch with Zenith so maybe I will go back and see if they will sell me some directly.
 

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OK, I apologize Charlie,

You plulled one of the three "don't touch that" jets, 9,14, 23. The main jet is often cruded so badly in place that it cannot be removed, and the other two are often correded into place also, best to just clean them in place with welders tip cleaning tools. The discharge jet, 22, can be removed, 9mm deep socket, and makes cleaning the others much easier.

Amazing how crudy the discharge jet itself gets.

I think GT Gravelyparts can help you, Parts for Aluminum Zenith Carburetors

Roger,
 

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Discussion Starter #9
Well you cannot install a smaller jet if you don't take the old one out. I can see there would be no real reason to remove it on a regular rebuild. I am going to lower the fuel level and see if that helps in setting idle. I turned the idle screw out 5 turns with no notable changes in idle. This carburetor is on a two-stroke Frazer Rototiller and was the factory replacement for a Tillotson YC9A.

So far I have emailed Gravelyparts twice and they have not answered. Guess they don't want to sell me parts.
 

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You could try rototillerparts.com or Zucks rototillers. It's been awhile. But if I remember correctly turning the idle needle in richens the mixture and turning it out leans it on this carburetor. It seems to me you might have worn throttle shaft / bushings, plate or bore.
 

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Discussion Starter #11
You could try rototillerparts.com or Zucks rototillers. It's been awhile. But if I remember correctly turning the idle needle in richens the mixture and turning it out leans it on this carburetor. It seems to me you might have worn throttle shaft / bushings, plate or bore.
Well I have been in touch with a Zenith tech and he is the one who ask me to remove the idle jet to verify the #. If the throttle shaft was worn, I would be lean. In fact I am trying to purchase the jets from Zenith directly since no other parts place wants to answer my emails.
By the way, I am the owner of Zucks Rototillers and I do not have Zenith parts.
 

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McDonald Carb Parts, search the interweb.
They have all kinds of jets, screws, floats, gaskets, etc. for the Zenith carbs.
Worth the look.
If you have the carb number (round disk riveted on top) it is a big help.
And they don't gouge you with the shipping (free if you order enough parts).
 

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Discussion Starter #13
McDonald Carb Parts, search the interweb.
They have all kinds of jets, screws, floats, gaskets, etc. for the Zenith carbs.
Worth the look.
If you have the carb number (round disk riveted on top) it is a big help.
And they don't gouge you with the shipping (free if you order enough parts).
Thanks, I just emailed them this morning and already heard back from them and they have the jets I want. Great!
 
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