Premier concentrics fuel level from factory.

johnm · Oct 4, 2023

marshg246 said:
If the fuel level is between .17" and .24" below the edge of the bowl, how is it possible to overflow? Are you measuring with the bowl on or off the carb?

The correct measurement is .17" to .24" as stated here: https://amalcarb.co.uk/technical/optimising-mark-1-concentric-fuel-levels

It is more important that the fuel level be the same in both carbs.

A quick check is to remove the bowl, put a thumbnail on the pivot pin and turn the bowl upside down. If the edge of the float across from the pivot is even with the edge of the bowl, you're good.

I have gone back and forth on carbs with the level set according to the Amal recommendation and had flooding which normally clears if the carb is given a tap with a screwdriver handle. Almost certainly the float needle is sticking.

The cure is not to adjust the fuel heightagain if it's correct but rather to stop the float needle sticking or jamming. Which can be very frustrating and time consuming to achieve. As mentioned many times gently smoothing the slot the needle moves in, checking the gasket clearance and ensuring the float has no roughness or mis shaped part can all help.

marshg246 · Oct 4, 2023

johnm said:
I have gone back and forth on carbs with the level set according to the Amal recommendation and had flooding which normally clears if the carb is given a tap with a screwdriver handle. Almost certainly the float needle is sticking.

The cure is not to adjust the fuel heightagain if it's correct but rather to stop the float needle sticking or jamming. Which can be very frustrating and time consuming to achieve. As mentioned many times gently smoothing the slot the needle moves in, checking the gasket clearance and ensuring the float has no roughness or mis shaped part can all help.

The float needle should not be touching the side of the tube above the seat. When adjusting the float, hopefully you don't bend where the needle sits but rather the metal to float connection. The entire metal piece needs to be flat. Also, can we assume you are using the silver float needle that came with the carbs?

johnm · Oct 4, 2023

marshg246 said:
The float needle should not be touching the side of the tube above the seat. When adjusting the float, hopefully you don't bend where the needle sits but rather the metal to float connection. The entire metal piece needs to be flat. Also, can we assume you are using the silver float needle that came with the carbs?

Hi. Yes to the aluminium needles.

Perhaps no to the bending location. I shall be more careful in future I think.

Fast Eddie · Oct 4, 2023

The float tang appears pressed on these carbs and can have a burr. This can foul on the needle and prevent proper closing. A close look and a careful de-burring And polishing with emery works well. It’s the same potential issue, and cure, for new MK2s as well.

Someone on here alerted us to this, I had a very infrequent intermittent flooding issue, I polished my tangs (ohh Matron) and all has been well since.

L.A.B. · Oct 5, 2023

Amal Stay up float. Version 1 and 2. Wheres the photo?

Sometime in the past maybe three years I recall reading a note with a photo describing the updated version of the stayup float. I'm not talking about the original plastic float versus the stay up float but an update of the stayup float which prevented the sticking of the float needle and erratic...

www.accessnorton.com

Mart UK · Oct 5, 2023

I had a little nib on the float spindle. It looked deliberately cast, but my sticky float ended when I filed it away.

black cat · Oct 5, 2023

L.A.B. said:
The ticklers can't fail to press down the floats unless the roll pins are set too high in the buttons so the pins need to be extended from the buttons.

How do you extend pins?

L.A.B. · Oct 5, 2023

black cat said:
How do you extend pins?

Grip the tickler button with pliers or grips (protecting the surface from scarring), hold the pin with another pair of pliers/grips and twist the pin further out of the button. (I suggest about 1/16" at a time then test)

The tickler installation instructions showing the assembly.

Tech Tip: Amal Concentric

Today we will be covering how to install the new Amal Concentric extended tickler. This extended tickler will allow you remove the original style unit to a more modern and clean version as used on the new Amal Premier Concentric carbs. Read the full post today

www.classicbritishspares.com

black cat · Oct 5, 2023

Thanks!

Premier concentrics fuel level from factory.

johnm

marshg246

johnm

Fast Eddie

L.A.B.

Moderator

Amal Stay up float. Version 1 and 2. Wheres the photo?

Mart UK

black cat

L.A.B.

Moderator

Tech Tip: Amal Concentric

black cat

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