Float level, (height) PHM40

I was checking the air filter on my 1000s so while I was in the carb area I thought I would drain the float bowls just in case any water was lying in the bottom .
When I took one of the bowls off, one of the floats had petrol in it, dear knows how it got in, as no matter how I tried it wouldn’t come out, there wasn’t even any air bubbles when it was held under water!

Anyway I ordered new float, but I am not sure of the correct float level, I checked the other carb and it was 24mm, (lying on it’s side, rather than with the carb upside down and the float on top, as per Dellorto instructions, as the 2 floats and connecting arm in each carb are moulded as one and not 2 independant floats). However I do not know if the height/distance is correct for the PHM40, does anyone know what the float height should be and am I checking it in the correct manner?

I take it also if the float height was not correct , for instance , say 18mm when it should be 24mm, at idle I would need to compensate by adjusting the mixture screw?

Sorry if this may seem a bit basic but I just want to get it correct.
Cheersrbt15482012-06-16 23:22:17

The ol’ porous float strikes again


Table bottom of page 9.

To help you make a ‘L’ shaped ‘tool’ from card, the rectangular cut-out depth being ‘X’ mm as required.

Hi Mike H,
Thanks for that, great info, making a “L” shaped tool is a great idea!
Should be able to make one, as I make model cars as a hobby, like the one below.

float hight is 17.5 to 18.5 done mine today


When I did my PHF36s I used a credit card cut about which was long enough to touch on both sides of the float chamber flange.

There ya go …