THERE ARE SEVERAL THINGS TO
CHECK WHEN BUYING A SECONDHAND CARBURETTOR
[Reprint from South Wales A7 Club Magazine
- Dec >99]
ONE - Is it Austin Seven?
The originals were generally (but not all) marked >7' on the flange that bolts the carburettor or to the
manifold and also C‑548 on the float chamber cover. The Austin 10 looks the same but should be stamped on the
flange >10'.
Check the size of the choke tube. The Austin Seven is 17 mm, the Austin Ten is
19 or 21 mm and this should be marked on the casting at the entrance of the
choke. If the choke cover is on it can be difficult to check the choke tube
size.
TWO - Check that the
carburettor is complete and nothing is broken.
Check flange with throttle in fully open position as this is often
broken.
THREE - Check the banjo bolt thread where it secures the petrol
pipe to carburettor.
Check threads of bowl where they hold the bowl to main body.
FOUR - Check spindle in
body.
If loose it can be repaired. Burlen Fuels will rebore and fit a new
spindle and butterfly disc for ,32 + VAT.
Spindles and discs cost ,6 each. (See
Roger Ballard)
FIVE - Check choke flap
spring.
If it is broken it can be replaced.
I believe from my experience, the following is the difference in the
carburettors, but I have not any information to confirm this:
- There would appear to be two types of 26VA
carburettors.
- The design at the top of the barrel (or body) is
different.
- The passages at the air regulating screw are
different.
- There are two types of bowls, deep and shallow.
- These bowls could have been changed.
I suggest that the earlier carburettor has the single airway at the top
of the body and it is fitted with the deeper bowl. The Zenith spare parts
schedule shows the shallow bowl fitted to the body with airways which are
straight, one at right angles
1932 V type Carburettor - Removable choke tube and different choke control.
Choke cable does not operate throttle linkage.
Later 26VA Carburettor - Type fitted with deeper bowl.
Ruby 26VA Carburettor - Type fitted with shallow bowl.