HotRodMatt wrote:"The carby is a stromberg. Weird little thing. Has an oil reserve in the top of it."
The oil reserve is so that some oil can go down the carby to lubricate the vanes. Usually a much thinner oil and with something added to make it combustible so as not to foul the cylinders.
nope, sorry, thats not correct. strombergs and SU carbys use the oil resevoir as a damper. the carb uses the pressure difference between the inlet side and atmosphere to lift a piston (SU) or diapragm (Stromberg) which in turn lifts the needle out of the jet, therefore providing consistent fuel metering depending on the engine's air requirements.
The oil is a damper, otherwise when you snap open the throttle, or the pulses in the inlet manifold, cause the piston or diapragm to bounce around, causing poor fuel metering.
usually a thin machine oil is recommended. you can substitute the oil with thinner or thicker oil to correct some metering issues too.
*edit* whoops! someone beat me to it 😀
[Edited on 19-8-2003 by Secoh]
