Scott -
It sounds to me that your carbs are supposed to have some kind of
automatic choke on them. If they were fitted to a sedan of some kind,
that would be the case probably.
Regardless of this, the car should not be idling so slow. The slow
idle speed screw should be working... what you describe suggests that
the slow idle port is blocked.
The most common reason why the port is blocked is when the carbs are
fitted with a non standard air filter and/or air filter gasket (or
possibly the airfilters are mounted upsidedown).. There should be two
small holes (under the main carb throat) that is on the carb face
where the air filter mounts. These holes must remain unblocked. If
they are blocked, your slow idle speed screw will not work.
Finally, on the slow idle speed screw, counterclockwise twisting is
open, clockwise is closing.
Hope that helps,
Alan
'53 BN1 '64 BJ8
On 5/1/05, scott@scottjgraham.com <scott@scottjgraham.com> wrote:
> Hi listers - need some help on my Healey BJ7 carbies.
>
> The car was converted to a triple SU set-up (I was told by the shop they are
>2" and have assumed they are the HD8's used for Healey BJ8's).
>
> The carbies have been overhauled by a reputable local shop but they were
>unable to adjust them to idle correctly. The carbies only have one adjusting
>screw & the shop has adjusted them to the max but the highest idle speed
>possible was 300RPM at which they constantly stall.
>
> I have used my pedal stop to bring the idle up - but this is far from ideal.
>
> When looking at the carbies, they do not match the illustrations in my SU
>manual for either HS or HD type carbies. Neither can I find the carbie serial
>numbers there or on the internet. The carbies lack (by design):
> - Fast idle adjusting screw
> - Throttle adjusting screw
> - Jet adjusting scew
> Instead, they only have a screw in the location marked in the book as a "Slow
>running" volume screw. I was told by someone else that these may have been
>later emissions compliant SU's.
>
> Can you please help me identify these carbies. The numbers on the units are:
>
> - Front: carby body - 709c; bowl tag - AUD 157c; junction with manifold - C
>13 6.
> - Middle: carby body - 709c; bowl tag - AUD 157f; junction with manifold - C
>13
> - Rear: carby body - 2044 (IGN); bowl tag - AUD 157c; junction with manifold
>- C 9 6.
>
> Thanks
>
> Scott J Graham
> 62 BJ7
> 60 Bugeye
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