Stay up Floats

In my monobloc carbs there are black floats..Are these stay up floats and why would the float level be too high when they are used?...Bike was running rich and I checked fuel level ...Found level was over 1/4" too high..Wondered if anyone else has ran Into this problem? Now that fuel level is correct the tickler won't work...

Beach said:

In my monobloc carbs there are black floats..Are these stay up floats

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Like this?
http://britcycle.com/Products/691/691_376083a.htm

Yes like that

The fuel level is set by the needle and seat, plus a shim washer under the seat. The Norton Manual P106/P (no date) states:
"floatchamber needle seating 1/8" diameter. Seating raised by 1/32" washer - shortened tickler fitted."

I had the needle gouge a depression in the plastic face where the needle bears,(the one in LAB's pic appears to have a metal face) causing the fuel level to rise. Being a poor college boy at the time, I fashioned a bodge using very thin brass shim stock. This covered the face, giving the needle a brass surface upon which to bear, and wrapped around and under the face. It is still there 45 years later. Perhaps your level problems are of a similar nature.

BTW, If anyone substituted a seat with a different size orifice (the 1/8" cited above), the geometry will be upset and the fuel level with it.

I hope this helps.

Slick

Didn't realize the float needle chamber came in different sizes.....

Beach said:

Didn't realize the float needle chamber came in different sizes.....

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The spec is 1/8" and should be stamped on the seat (.125). That said, my Atlas came from the factory with a 0.200" orifice and a needle having a wide cone angle. This is one of the several anomalies I have observed in my Atlas. Dunno why.

I recently ordered a new needle and seat from Amal, ordering by part number given in the Amal site for Atlas models. The seat which came, was stamped .125, and when I installed it, I immediately knew all manner of "not right" broke loose. The float level was dramatically altered and the float rammed against the tickler. I ended up keeping the old 0.200 seat and needle. Perhaps what I observed is similar to what you are seeing.

You may have to add or remove the shim washer under the seat to get it right, but I would go with the .125 spec as a starting point.

Good luck sorting it out.

Slick

So are you still using the plastic needle and original seat?

Beach said:

So are you still using the plastic needle and original seat?

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Yes. Want to buy a new Amal needle and seat only recently removed from its package and never having tasted fuel?

Seriously, I was afraid I might impair the performance I enjoy with my Atlas by reducing the fuel supply orifice. It would also affect the float level, unless I removed the factory supplied washer. As I said, all manner of "not right" popped up when I put in the new needle and seat.

That said, I still think it prudent for someone to start with a factory spec when trying to sort out a problem.

What is the current status of your problem?

Slick

Waiting for resleeved slides to return....I was able to get fuel level correct by turning needle seat down where it meets the carb.....When I did this the float was so low that tickler didn't work....Before I did this the float level was too high and caused bike to run rich..

Got my resleeved carbs back and installed them yesterday..I got new .125 needle seats and installed with aluminum Vito needles...My float level is correct now and with the resleeved slides I can turn idle down until it stalls....The bike now idles perfectly with no fluctuation...The loose slides were definitely causing high idle....