Re: stag-digest V3 #7

[Mike Wattam <101714.1343@domain.elided>]

DISTRIBUTOR
I am assuming your car is American or Australian specification.

The vacuum housing should be connected through a flexible rubber elbow to a
small bore black plastic pipe which runs to the radiator header tank where
there is a small thermo-switch.  

From there, the pipe goes back to half-way down the left cylinder head
cover where there is a small upright metal tube (vapour trap).  From there
the pipe goes up to the carburettor intake.  In the centre of the
carburettor adaptor (between the carburettor flanges and next to the
central holding-down nut) there should be an adaptor screwed in.  You can
see these details in the Stag parts book page 02-44.  Let me know if you
need to have me send you this as a graphics file.

However, as the vacuum advance makes very little difference to economy or
emissions, my guess is this equipment has been stripped out as a waste of
space.  

For your information UK cars have a simple pipe running from the vacuum
housing to the carburettors, with no devices in between.  If this item is
missing on UK cars, it makes no noticeable difference to the car.

Related issue 1 - check whether the vacuum works by sucking on a connected
hose - you will probaby also find the diaphragm punctured.

Related issue 2 - remove the distributor cap and see if there is free play
between the distributor base plate and the vacuum pushrod.  If so, the
small screw which locates these together is worn out.  Fitting a new plate
assembly (with included screw) will give a much better tickover and
possibly slightly improved performance.

Mike Wattam
Triumph Stag Register