Amal float level

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I have read all the links to setting the float level . My bike is running rich when riding, at idle it is fine by the gas analyser and the mercury guages show the balance spot on after checking timing etc. Rev up to 3000rpm and the analyser goes into the rich scale. Run up and down the freeway and the plugs show rich even after dropping the needle clip to the top groove. Moved the floats up and down as per the links on the amals and at the setting suggested .080" would not idle and was way to lean on idle plus the ticklers did not reach the floats to flood carbys on start up. The floats were set above the float bowl when I first stripped them and was way too rich but the ticklers reached them. I have them set just below the bowl edge and the ticklers do not reach the floats but it idles perfect. I am going to strip the jets out and see if I can measure the needle jet size and will see if I can get a carby kit with new jets for next weekend but would love to know where the float should be set. I even conected the fuel lines to just the float bowls and measured the actual fuel in the bowl at one of the recomened settings and it was way to low. Thanks.
Ian
 
Scruff — try setting the float level so that the top edge of the float is 2 mm above the face of the float bowl. This is the figure that is recommended. See this link:

http://www.jba.bc.ca/Bushmans%20Carb%20 ... html#FLOAT

However, in practice, you might find that this is too rich, in which case try 1 mm.

I turn the float bowl upside down, hold the float pivot pin firmly with a finger, making sure not to touch the float itself, and let the float needle sit on its the seat just by the weight of the float alone.
 
The link says `below` the face of the float bowl but since you are looking at it upside-down when measuring then I guess it would be ~above~ . Basically the top of the float needs to remain within the bowl when the gas pushes up on it.

Or maybe I've been doing it wrong for a long time.

Russ
 
Read the artical again, the float level should be just below the front edge of the float bowl, not above as stated in the other post. .060 to .080 thousands, or 1 1/2 to 2mm.
If the slides are not worn out, overly rich running is normaly worn needle jets or needles or both. The needles are stainless and don't wear too fast but the needle jets are brass and do wear quickly. The vacuum pulls the needle forward and wears the jet oval shape, .0005 thats 1/2 thou, makes a big difference.

Ken G.
 
Thanks for the help. I had a play with the level as per those two sites and because my ticklers are to short at those settings is why I set it at about 1millimeter and it ran the best at that setting even though the ticklers still do not reach the floats, thats why I thought I would see what every one else had set their heights at. Seems as though the 80" is about right. I will investigate further at the weekend as I had to go back to work today after my Easter break and you all know how that puts you in a different frame of mind. The bike is back inside the house now and the boss lets me do anything down stairs in my play room but she draws the line at the smell of petrol. Do not want to burn the house down, will take it back out to the garage at the weekend. I suspect the advice on the needle jet is close to the problem.
Thanks again Ian.
 
The top cap piece of the tickler is pressed onto its shaft. They can be pressed together too far. Pull them apart slightly and you should have enough length to reach the floats.
 
Batrider Thanks for that advice, I was going to pull them out at the weekend but I will try your advice first.
Ian
 
Scruff said:
I had a play with the level as per those two sites and because my ticklers are to short at those settings is why I set it at about 1millimeter and it ran the best at that setting even though the ticklers still do not reach the floats, thats why I thought I would see what every one else had set their heights at.


Many Amal users have found that setting the floats to 1mm below the bowl face is best.
 
L.A.B. I was hoping you would have a view on the levels. The choice of 1mm was just trial and error with 2 mm not able to set the idle with the pilot jets and with the float parralel to and horizontal to the base at 1mm+ on opening the throttle was way to rich. This was the height they were set at when I first pulled them apart. My 930 ticklers are one piece and peened over where they touch the floats to stop them coming out of the carby bodies. I have a set of 932,s and the ticklers on them are made up of two pieces and are longer so they would touch the floats at the lower setting.
Ian
 
This is interesting stuff!
Depending on who you ask about setting the Amal MK1 float level you get anything starting at a low 3-4 mm below the edge up to 1 mm above the edge.
Last season I used 2 mm below (checking the level by turning it upside-down). This worked fine for me but now I tried to use approximately 1 mm. The bike is very easy to start (did some othe work so might not be depending on the float level) but I now get a little bit of floading on one side. Not sure if this is entirely related to the float level?

What is your experience with highest float level setting without getting flooding problems?

Regards,
Per
 
Per G said:
What is your experience with highest float level setting without getting flooding problems?


Personally, I've never needed to experiment with float levels. I check they are 1mm below the flange, and that's it.

The only time I had a flooding problem was when a float cracked along the joint, and fuel leaked into it.
 
Thanks LAB!
I fitted new floats so maybe it;s probably a good idea to drop the bowl and check that the new float is not leaking and maybe try a new gasket too.

Cheers,
Per
 
Just a quick update. Ordered new main jet, needle jet, needle and float needles by Australia post C.O.D. on Tuesday and may not receive before the weekend. Will report on results. If not good will buy new carbies at $325.00 AUD. My supplier told me that Amal were under new owners and the quality had dropped, any comment on this info? My purchase of the Trispark will be put back a little if I do as I have spent much more than the $900.00 stimulas payment since Easter but she is on the road and I still love her, maybe its all the quality time I spend down in my playroom playing with the little things that go with ownership of a classic.
Ian
 
My supplier told me that Amal were under new owners and the quality had dropped, any comment on this info?
Have heard the same but just bought new bodies and chromed brass slides. Only issue I had with these newly tooled castings was a tight spot in the float pivot area (old floats) jamming the floats up or down. Relieved the metal and carbs work a treat with better mileage than ever I had with new carbs from 7-8 years ago. The new castings certainly look good.
 
Scruff said:
My supplier told me that Amal were under new owners and the quality had dropped, any comment on this info?


Burlen Fuel Systems has owned Amal since 2003, and there's been no recent change of ownership as far as I'm aware? I do know they have had some problems with their production quality in the past.

http://www.amalcarb.co.uk/profile.aspx
 
New jets etc arrived Friday. Fitted and set float heights at 1mm, needles were about 2mm longer and had one extra mark on the top above the 3 grooves, fitted needle clip in middle groove and the jets were 220 main and 106 needle jet. First play it would not idle at a constant 900/1000 rpm it was all over the place even when I did not touch the idle screws or the pilot jet screw. Mind of its own and would run up to 2500RPM back the idle speed of a fraction and it would drop and stall. Sprayed WD40 onto the auto advance as I thought it was the problem even though I had stripped the AAU and used the best parts out of the two I had and it ran a little more consitant so on with the helmet and of for a test ride. Called into a mates house and it was ticking over like a clock. Back home and checked the gas readings and were ok. After lunch went for a ride down to Kiama blow hole via Jambaroo and back home, still running good just need to sort the front brake out, not much there and a little bit out of round which causes a judder when braking hard. New shoes were fitted and still have not beded in yet but I may have to strip the wheel to fit the hub in the lathe and skim the drum true.
Ian
 
All this concern over 1mm here and there is mistaken as are lean concerns. Fuel is picked up by the fuel circuits in about the last half inch of the carb bowl. In order for the engine to receive fuel ,the pick up points must be covered with fuel. I don't think you could set the float low enough to stop the engine from running. You could , however, set the fuel level so low that on full power, the engine consumes all the fuel before it can flow back in to replenish what was used up. Then, you have a lean condition. The engine will sputter and misfire due to lack of fuel.A rich condition on the other hand can be easily had with the float level too high or with the needle not seating correctly due to the float hitting an obstruction or simply not sealing effectively. Then you are essentially in tickle mode. The only way fuel gets out of the fuel bowl in this mode is up through the main jet and into the center of the throttle bore, through the idle/low speed circuit that you control with the mixture screw, or out the tickler bleed hole as it does when you tickle the carbs to get your fingers smelling like fuel. In fact, if you see slight wetness at your tickler with the fuel taps on and your bike just sitting on its stand, you have a high float level or seating problem. If not corrected and you fail to shut off your fuel taps, the fuel will continuously run into the sump and dilute your oil and probably cause you grief. I have had this happen on a Triumph and it actually put a cup or two of fuel into the primary which has a connection to the sump. If anything, I prefer to err on having the float level a tad lower than called for. If the ticklers do not reach to open the needle and seat you just extend them a tad. If they will not budge when you try to elongate them you can put a small screw up the center to add a tad of length.
 
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