- Adjustment of the float levels : With the cover turned up-side down, the distance between the float and the cover gasket must be b = 4.75 + 0.1 mm If it is not, adjust the tongue (3) which must, in this position, be parallel to the joint face of the cover and 19.75 mm away from the paper gasket. - When this cover is in its normal position, the distance between the float and the cover gasket must be : e =11.5+0.1 mm If it is not, adjust the tongue (4).