What is the best way to check the internal condition of a rotary? I hear compression tests may not be a sure fire way to determine condition of apex/corner seals etc.I'm looking to buy an fd and want to make sure I know what I'm getting myself into.

 

compression test will indicate condition of all the seals/springs that allow the rotors to seal, making compression. u wont really know about the oil control rings and they're ability to seal until the engine is running. the worse they are, the more it will smoke from the excess oil it's burning. as for condition of rotors, stat gears, bearings, eshaft, and housings go, it will have to be disassembled for that.

 

Of course like any other car the condition of the engine should be considered. And since it's unique that garners the attention. But also, just like any other cars, there are more things to consider. From the 3rd Gen. FAQ sticky at the top of the this section:

Buying a Used RX-7

http://www.marx7.org/infocenter/faqs/3rd_faq_main.html

Buying a Used RX-7

https://www.rx7.org/Robinette/buyaused.htm

 

rxtasy3 is it normal to hear like a scrapping noise from a keg while turning by hand. Keg was a s4 13B n/a. Guy had engine sitting for a couple years in garage. Added atf oil and started turning by hand. I could hear some strong puffs but there was a scrapping noise every time the rotors would turn.