I uploaded this chart awhile OK with out much comment but I think
it is worth closer study. This is from SAE paper 922375
by Mazda. The devel. of Lube Oils...for Rotary Racing Engines.

Note the upper right hand corner where it says % of residue by weight.
polybutene is by far the lowest at 2%. I assume polybutene is synthetic
and is used in two cycle oil judging by my own and Paul Yaw's heat 
test on oil.

Mazda test temperature at 280 C or 536 F was higher than mine at 500 F.
My test was one hour  while theirs was ten hours. My test was a subjective
look at the residue while Mazda weighed it.

Note also that polyolester residue is higher than mineral oil.
Does anybody know what the base stock of Mobil One is?

Mazda knows they need a better oil to lube the apex seal and I hope
They see their way clear to providing a separate apex seal oil tank for the
apex seal lube oil in the coming RX8. Level sensors and an automatic switch
by all means.

Paul Lamar
 
The AirCraft Rotary Engine NewsLetter.              Powered by Linux.

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