I posted the message below on the cartalk forums, but haven't got a response there yet from anyone familiar with the problem we're having.
I'm new here.
I don't have internet at home presently, but I'll check back in a few days.

My dad "inherited" a 1985 GSL, with a fuel injected 13B engine, that had been parked for serveral years.
We oilled the rotors and towed it a couple of miles.
Then put the plugs back in and cranked it, but it wouldn't start.

We poured some fuel into the intake and it fired.
After the engine reached maybe 1500 RPMs (our ears aren't tuned yet to normal Mazda wankel operation) and above It would continue to run on fuel from the tank

If it was throttled back below about 1500 it would die and wouldn't restart unless fuel was added to the intakes.

I'd appreciate it if anyone with knowledge about the engine could share insights into getting fuel to this engine at the lower RPMs.
Thanks,
Dale Myers

 

It's a shot in the dark, but perhaps your injectors are a bit clogged causing less fuel than required ?

 

Welcome to the Dark Side.

Make sure the fuel is fresh, replace the fuel filter and check for vacuum leaks on the intake duct to the throttle body. Might run a can of Seafoam through it with 1/4 tank of gas.

There is a good section on trouble shooting SE idle problems in the following thread.

https://www.rx7club.com/1st-generation-specific-1979-1985-18/1st-gen-rx-7-faq-page-237777/

 

There is a drain plug on your tank, use it and dump that crud.

welcome to the dark side.....

 

Thanks for the replies.
I didn't mention that we had cleaned the fuel system, but only to the injection pump supply side.
Thanks,
Dale Myers