wintergrn

I've found that if the oil is about 1/4 inch above the low mark, and I add 1/2 qt, that takes it to 1/4 inch below the full mark. This is on the original '04 dipstick.

Search for the TSB for the "new" dipstick -- it has markings every 1/2 qt -- it looks like the total distance between full and low is a little over 1.5 qt, but it's not a linear scale.

JM1FE

Absolutely wrong. Read post #8 in this same thread for an explanation.

allmotorRX8

i know that the 8 consumes gas on its daily basis, i am only wondering if babying it during its initial break in period will have any affect on future oil consumption. if that were the case, then it seems like babying it for the first 1000 or so miles is well worth the effort, as hard as it may be to keep the engine from winding up.

JM1FE

I'm going to assume you meant '...consumes oil...' not '...consumes gas...'

OK, I didn't make it clear.

Why does a piston engine 'consume' oil? In a piston engine, oil should be below the piston rings in the crankcase, and not above the piston rings in the combustion chamber. The cylinder walls are lubricated by oilsplash from below as the piston rises, and should be squeegeed almost clean by the rings as the piston descends. Therefore, in order for a piston engine to consume oil (not counting leakage) oil has to get by the rings. Improper break-in can cause wear situations where the rings do not properly seal, therefore leading to oil consumption.

Why does a rotary engine 'consume' oil? In a rotary engine, the only way to lubricate the seals is to *inject* oil into the chamber for the apex seals to have an oil film to lubricate as they spin around. There's no up-and-down division of what's 'oily' and what's 'not oily' as in a piston engine. Because the oil is *injected* it gets metered at a fixed dose depending on engine temperature and RPM. Given a properly-functioning oil metering pump, a 0-mile and a 200,000-mile Renesis should use the same amount of oil at the same RPMs and temperature, since it will be metered the same way on both. Minor variations may occur from differences in the pumps, carbon build-up on the oil outlets in the engine, etc., but everything else being equal, the only wear parts involved (the apex seals) should not affect oil consumption regardless of break-in style. I think break-in with a rotary is partially about seals, and partially about thermal conditioning of the metal.