An ATF question
 

I have been think about this for a while, so I wanted to ask you guys to get you opinion on it. I know alot of people use all kinds of different oils in rotarys, diesel oil, conventional and synthetic oils and 2 cycle oil in the gas tank. So what do you guys think about ATF? Has anyone used ATF when changing the oil and filter? I know it has a lot of detergents in it, and it has friction modifiers for automatic transmissions so it should be able to stand up to the abuse injected inside the rotary engine. I am not trying it or anything yet, but what do you guys think?

ATF is auto tranny fluid. totally different than motor oil. ATF works more like hydrolic oil. it's how the tranny actually works, not just a lubricant. not to mention other properties involved that make them differ. i wouldn't attempt to use it as a motor oil.

Oh I never knew that, I thought it was a lubricant. Thanks for posting. I thought if it was a lubricant the detergents would be great to keep the motor clean inside. My friend use ATF and runs it in cars with motor oil for about 5 to 10 minutes to clean them out. You would not believe how good the detergents are it takes all the gunk out of the engine. I am just going to stick with diesel oil.

u don't have the problem with the oil gunking things up in a rotary like it does in piston engines.

ATF is a deterngent and a lubricant(autos still have bearings...) but it is not meant to be used in combustion engines for these reasons:

1) it's too thin to protect high vertical load bearings like rotor and stat gear bearings
2) the thin viscosity will allow it to pass into the engine during running and burn off, causing thick plumes of white smoke because transmission fluid is not meant to be burned as readily as engine oils can
3) the seals in any combustion engine are made to withstand engine oil, transmission fluid has different characteristics which cause the typical oil seals to swell and eventually leak. transmission seals are made for transmission fluid, engine oil seals are made for engine oil.

you can get away with using a fractional amount of transmission fluid mixed with engine oil(about 1 part of ATF to 10 parts of engine oil, in other words half a quart to a full oil crankcase. keep in mind i have not tested this in rotaries but only in piston engines, i cannot guarantee that the oil seals will survive if you try it.) to clean the crankcase but it should not be left in there for long.