HX 181 fuel level

[aumick10]

I am trying to get a HX 181 fixed to run on a 1925 JE. I have fitted new float, float arm and pivot pin. New needle and seat. I set up the float with 1/2" height. The fuel level is effectively the same. When i hold the bowl in a vice, it will sit there without overflowing. When i fit the bowl to the body, i have a problem.
With the air horn removed, i can see the fuel wicking up the high speed needle tube, and spreading around the inside of the air inlet. Eventually this fuel will build up until it starts dripping out the bottom of the air tube. This is only a problem if the bikes sits for a while with the fuel on.
Is this a normal thing for the HX series, or should i be using a different float level.

[T. Cotten]

I am trying to get a HX 181 fixed to run on a 1925 JE. I have fitted new float, float arm and pivot pin. New needle and seat. I set up the float with 1/2" height. The fuel level is effectively the same. When i hold the bowl in a vice, it will sit there without overflowing. When i fit the bowl to the body, i have a problem.
With the air horn removed, i can see the fuel wicking up the high speed needle tube, and spreading around the inside of the air inlet. Eventually this fuel will build up until it starts dripping out the bottom of the air tube. This is only a problem if the bikes sits for a while with the fuel on.
Is this a normal thing for the HX series, or should i be using a different float level.

Two concerns come quickly to mind, Mick,..

The first would be if the float hangs up upon the bowlstem for some reason. Only inverting the indexed bowl and body together, and then sucking upon the inlet can assure that it is fully closing. (This often happens when a 1" model float has been installed in a 1¼ " model, which are quite similar.)

The second would be the construction of the float itself. Please beware of molded boatanchors weighing two or three times what they should:
HQUACK.jpg

...Cotten
PS: And of course, no float valve seals for long; The petcock must be absolute, or no carb will stay sanitary.

[aumick10]

Tom, when i put the bowl on the body, i leave the float needle cap off and can push the float up and down freely, so i don't think it is hanging up. I did have to move the float attachment screw slightly back towards the float needle so i may have a 1" float. The carb is not overflowing.
With the bowl off the carb, it operates as it should and will hold a level for as long as i like. The issue seems to be petrol wicking up the needle "tube" and overcoming the fuel surface tension.
I tried the bowl on another body with exactly the same result.

[T. Cotten]

Tom, when i put the bowl on the body, i leave the float needle cap off and can push the float up and down freely, so i don't think it is hanging up....

With all respect, Mick,..

The 'suck test' takes all the "think" out of it.

Is your float a full 2", or more like 1 7/8" or so?

Is it molded, or look like a sponge where its machined?

...Cotten
PS: You were quite correct to title the thread 'fuel level'. I'm guessing it was the same as for later DLX/L&L designs, 5/8".
So the trick is to get your chosen float to produce that (and survive modern fuels).

If the float height in this diagram is ½", it suggests the HX fuel level might also be 5/8".
HX at idle.jpg

[aumick10]

Tom, passed the suck test. Float is about 2.15" OD. It is thinner on the side away from the needle. With the float set at 1/2", it is nowhere near parralel to the bowl top. Will go back to original float arm and start again.
Thanks.

[T. Cotten]

Let us hope your float hasn't swollen, Mick...

Do you have a scale that can weigh it by the gram? (Without hardware it shouldn't be much more than about three grams.)

I noticed in your first post that you installed a 'new needle and seat'. Are you certain you have the right bowl?

181rawRGT.jpg
Replacing the seat ain't easy!

.....Cotten