[Healeys] Setting SU HD Carburettors

[John Sims]

You can find Steve Byers instructions for HD8 adjusting on the Technical
page, Fuel System section of my site.

John Sims, BN6
Aberdeen, NJ
www.healey6.com


-----Original Message-----
From: healeys-bounces at autox.team.net [mailto:healeys-bounces at autox.team.net]
On Behalf Of BJ8 Healeys
Sent: Friday, August 17, 2012 10:07 PM
To: 'Forum'
Subject: Re: [Healeys] Setting SU HD Carburettors

Derek, the confusing and contradictory instructions that use multiple names
for the same adjustment part is the main reason I decided to write my own
instructions for adjusting HD8 carbs.  The SU manual tells you how to adjust
a single HD carburetor, but for a multiple carb installation it refers you
to another section where the "throttle adjusting screws" are mentioned and
shown, but these (as shown) are not present on an HD8 carburetor.
I based my instructions on the SU manual and BMC workshop manual, but tried
to use consistent nomenclature and illustrate the process with photographs.
These have served me very well, and I have shared them with others who have
reported they worked for them, too.

The last time this subject came up on the list, it was suggested that rather
than setting the final fast idle speed with the throttle screws, as my
instructions have it, the idle should depend only on the slow idle
adjustment with the throttle screws being used only to set the choke
operation.  I considered this, but decided to stay with the idle mixtures
and carb balancing being set with only the "slow run valves", then
increasing the normal idle speed to 1000 RPM with the throttle screws.  As
they say, "it works for me" (and others).

Steve Byers
HBJ8L/36666
BJ8 Registry
Havelock, NC  USA