++> /The difference is that the GT6 (as were most Triumphs) was delivered
++> /Stateside with either the Federal or California emission systems. Federal
++> /was merely equipped with two Stromberg 150 CDs. The California system on
++> /the other hand had 150CDSEs and a vaccuum switch and chaarcoal cannisters
++> /to recirculate unberned fuel gases.
++> Hmmm, my GT6 is a CA model and it has the 150 CDSEs and charcoal canister,
+but
++> the only vacuum switch is on the radiator.
I think all the plus models, after a certain date, had an emission
system on it. I'm pretty sure the vacuum retard system we're discussing
matured past the vacuum switch on the throttle linkage pretty quickly.
Later CDSE's had a port drilled in the carb throat which is just barely on
the vacuum side of the throttle plate when the plate is closed. When the
butterfly is opened, even slightly, this port is exposed to atmospheric
pressure (or something close). This accomplishes the same thing as the
throttle linkage operated valve, but is one heck of a lot simpler and
reliable. The radiator mounted vacuum switch Mike talks about on his
radiator is a further emission device which blocks vacuum advance when
the engine is below normal operating temperature.
The charcoal canisters are part of yet another system which
collects and condenses fuel and crankcase vapors. Early fuel tanks and
engine crankcases were vented to the atmosphere. Later cars have a
closed venting system which includes the charcoal canisters to prevent
evaporative emissions.
--
William Woodruff woodruff@caen.engin.umich.edu
Ann Arbor MI
|