I recently had an opportunity to disassemble my proportioning valve. There are a lot of interesting parts in there and I’d like some input from someone that is familiar with the workings of metering valves of this type.
We had the best minds at Donut Derelicts looking at it Saturday but there were no definitive answers on how exactly the metering function takes place. Unfortunately the top dog hydraulics mind did not show so it will be next Saturday before we have a good explanation from him.
The valve can be seen on Bill Taylor’s web page on Pantera Place at http://www.panteraplace.com/page199.htm Note how the upper spacer ring controls the space between the lower side of the piston and the piston seal ring.
We pretty much understand how the fluid flows though the valve but we are not in total agreement how the pressure gets regulated. We also know that the standard test to determine if a proportioning valve is functioning, is to observe the outward movement of the piston shaft as brake pedal is depressed hard.
Mike
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