[bobeeb]

I have a 1972 silver shadow LRA12701
Two questions needed to be answered.
What is the purpose of the Throttle Stop Vacuum Actuator? Mine is disconnected and the Vacuum retard tap has apparently been removed.The Vacuum retard line runs directly to the distributor and the T line that would normally run to the retard tap is plugged.

I noticed the "A" float chamber vent hose is disconnected from the Fuel Receiver and Float Vent Valve Chamber. When I connected it I experienced fuel starvation during acceleration higher than idle (700 RPM).When I disconnect it the acceleration returns to normal. The "B" float chamber vent line is properly connected.

In both cases my Motor seems to run OK but I like to have things as they should be!

 

[guyslp]

Definitely check out Chapter K - TSD 2476 - Shadow/T Workshop Manual and you may get the answer to your question. This is discussed there.

If you're not aware of it, be sure you bookmark the Rolls-Royce Owners' Club of Australia Technical Library - Shadow & Derivatives Pages. There's a trove of information there, including the full Workshop Manual plus much more, that you'll find yourself referring to again and again.

 

[Paul Yorke]

It sounds as though you have a problem with your weakener system.

The vacuum throttle stop (if we are talking about the same thing) increases teh idle speed when the Air Con compressor is turned on,.

 

[bobeeb]

Vacuum Throttle stop Q

It sounds as though you have a problem with your weakener system.

The vacuum throttle stop (if we are talking about the same thing) increases teh idle speed when the Air Con compressor is turned on,.

Thanks Paul , I finally found its purpose in the AC section of the online Manual.My system has been converted to R134a . When I activate the compressor doesn't seem to need any more RPMs. Runs just fine & very cold!
I replaced the Vac retard tap and set it at 14 lb. at idle as per manual instructions.The vac retard mod on the distributor was getting about 24LB as it was connected directly to the vac source.

Will tackle the weakener system later but system works OK at this time.