BT7 Carb floats

[RonR]

Folks,

Section D.8 of the BMC shop manual notes that the carburetors float adjustment should be by use of a 7/16-inch diameter rod. This is for H4 carburetors.

Section DDD.6 notes that the float height should be adjured using a 5/16-inch diameter rod for 3000 Mk. II cars (HS4 carburetors.)
There is no mention on the float height for the original 3000 cars (BT7 and BN7)using HD6 carburetors.

What is the general view on float height for HD6 carbs?

Thanks.
Ron

 

[steveg]

Ron - you're right about the Bentley manual. I had thought it was less ambiguous than that.

Burlen's current SU Workshop Manual, Section "HD Type Carburettor: Routine Servicing", p. 21:

In previous threads some advocated a 5/16" float level as well as a float level based on the fuel down (IIRC) 3/16" or 5mm down from the top of the jet. The latter resulted in a 5/16" float level anyway. I ran 5/16" with my dual Air/Fuel Ratio gauges and noticed no difference between that and 7/16" - so I went back to the factory recommendation.