I seem to recall that the lack of a lubricity agent in JetA (needed for the fuel
pump) is one of the niggling little problems.  I know it's an issue for running
Diesel engines with their very high pressure fuel pumps; I dunno if it is an issue
with the 40psi (?) fuel pumps in the Mazda.  I wonder if it would be an issue for
the apex seal?

Russell Kent

JetA is essentially the same as no. 2 diesel with the addition of a trace additive for anti-icing, if I recall correctly. May also be tighter controls on heating value and volatility. From a lubricity perspective, it is fine in high pressure diesel pumps, which a direct injected stratified charge rotary would use. It is of no consequence for the apex seals, as they still require metering oil (if the fuel is getting all over the trochoid for seal lubrication, its not going to burn efficiently or cleanly).

The military turbine fuels, JP 5 and JP 8 might have lubricity problems, although the concern is probably overstated for products with relatively short service intervals. Over the road trucks, at hundreds of thousands of miles a year might have problems.

Jon

 
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