Ariel Owners Motorcycle Club

Good evening
I have used an Amal refurb kit on my Ariel leader carburettor and it leaks fuel from most orifices,
Can anyone advise me how to solve this tricky problem please.
Cheers paul

hi paul, it can be the float valve not shutting the fuel off or the float level is too high

I replaced the old float and needle in my 375 with new 'ethanol proof' versions from Amal and also added the fibre washer under the needle valve housing as is often advised when fitting the 'ethanol proof' components.

However, I found that with the fibre washer the new float and needle arrangement was rising so far that the float hit the tickler before it shut off the needle valve (ie fuel everywhere just as if the tickler was being held down.)

Longish story short, discussion with Amal pointed me to the shim packs they now provide to go under the needle valve housing so you can adjust the fuel level without using the too-thick fibre washer. (These only show under 376 although they're for the 375 as well so I hadn't found them.)
https://amalcarb.co.uk/monobloc-series/ ... ttors.html

HTH

SG

Hi both
Thanks for that, I have used the ethanol proof valve and will get the shim pack asap and give it a go
Cheers

i lowered the float level on my amal 375 in my 58 leader as i noticed the level was right up at a point it could easily flood the engine .
what i did was to turn down the float needle valve union face and check the level of float as i went , i have dropped the float by 1/4" down from an initial mark i made before i touched things .
you can turn down the face down of the union more than needed and then fit a fibre washer to lift float up but if you have different thickness washers can set the float to desired level , or could use the shim kit from amal .
i found that with original carb i could lift float but not drop it because there is no shim or fibre washer used on the original carb and float valve union .

i know with the concentric carbs you can simply alter height of float by altering the level of the pressed in bushing but with the monbloc it seems you could only go one way and not the other lol .
regards
ian

Hi Paul
I assume you know that the ‘pip’ protruding from the float bowl cover is the correct fuel level and you should be adjusting to suit?

Hi Ivor
Thanks for that, I will give all the welcome advice a go next week

Ah, so what you need to do is fit a clear plastic tube to the projecting pilot jet after removal of the pilot jet cover nut. The height of fuel in the tube should be seen to match with the pip on the cover.

Fantastic, thanks now I've got it

Might be a bit late but I had problems sealing the cover to the float chamber. Turns out these distort probably from over enthusiastic tightening of the screws. Martin Bratby can machine them flat and/or provide an exchange service.