float height

[ageing biker]

hi all, long time no post, hope you are all well,finally finished my 59 a10 project, the bike is running ok but when I go to start it I turn on the fuel, press the tickler and the fuel is dribbling from the tickler immediately, this suggests to me the fuel level in the float bowl is too high, 389 monoblock, plastic float and new viton tipped float needle, any thoughts on this, cheers John

[chaterlea25]

Hi John,
There should be a little tubular spacer thet fits onto the float spindle between the float and cover
This is easily lost and can cause flooding
Has a fibre washer been fitted between the float valve/fuel inlet and the carb body?
On an old carb there should NOT be one (they are only fitted to the recently remanufactured carbs)
Having one fitted to an old carb will cause the fuel level to be too high

HTH
John (another one!!)

[ageing biker]

thanks for the reply, its an old carb and no fibre washer is fitted the spacer is also in place. years ago I had the same problem with a bantam, however this had a brass float so I put a blob of solder onto the part of the float that acts on the needle and filed it down until the correct level was achieved, I can see no way of adjusting the fuel level so I may have to obtain a brass float and give it the same treatment.

[muskrat]

G'day John. The new stay up floats are adjustable http://amalcarb.co.uk/monobloc-series/389-series/floats.html
On the bowl cover just below the Amal is a pip. That is the desired fuel height. I think there was a topic here about how to make a clear stand pipe to check the height.
I have used the concentric type and found them very good.
Cheers

[ageing biker]

thanks for that, does anyone know how the new stay up floats adjust?

[muskrat]

Just like the old brass ones. Bend the tang that operates the needle. Plastic floats on steel pivot & tang.
Cheers

[ageing biker]

cheers will probably go for the new float, thanks guys

[wilko]

To check float height, just unscrew the idle jet hex cap and fit some clear plastic pipe and curve it upward next to the float bowl. Personally i've never had to adjust a float for any mono or eccentric.

[ageing biker]

hiya, just been out and started the bike, didn't tickle carb, no choke, no throttle, started first kick, surely this suggests an over rich mixture, and its minus 1 here

[metalflake11]

That does seem to suggest fuel level being too high in the bowl. I'd do as Wilko suggests to check, it's a very good tip and not one I'd heard of before.

[A10Boy]

Black plastic monoblock floats have a habit of fouling on the left hand screw boss inside the float chamber. A bit of judicious fettling with some emery on the float usually cures this.

[A10 JWO]

Hitchcocks Motorcycles are experts on Amal and will deliver parts overnight. Very good indeed.

Colin

[ageing biker]

just done the float height check using the clear tube method and its spot on with the pip on the float chamber cover, when the weather improves I'll go for a run and do a plug chop, thanks to all who replied to my query, cheers John