Hello, recently I just picked up a 1985 GSL RX-7 with the 12A engine, and its cracking over but its not starting. just to clarify I brought the car like this and it did run before because it has 127,00kms on it, but this my first time owning a rotary and something this old so mostly everything is new to me. so like I said its cranking over but not staring up. is has been worked on before I brought it but its nothing huge, just new starter, spark plugs, spark plug wires, alternator, belts and lastly a new carburetor. I have a video attached of what it sounds like cranking over (don't mine the country music in the background).

What I have done with it so far is check all the fluids so see if there is any in it which it has. also checking for air and spark which it has both, so I removed the spark plugs and cracked it over for a little bit to try and get any old gas out of the engine. once I installed the spark plugs back, gave it one more shot of cranking over with a little bit of gas poured into the carb and it also started for a second then went back to just cranking over like in the video. From that I suspect it to be a fuel related problem but I don't know where to start with it. so any help with that would be great and just any other things I should be to kept it running healthy once it runs.
Thank you!

 

you probably need to go through the entire fuel system, I'd start by checking the fuel level by looking at the sight glasses on the front and rear of the carb,they're difficult to see, but the level should be halfway across the glass, if not then you need to work your way back, fuel pressure at the inlet, filter, pump, tank. you should be able to hear the pump running or not when you switch the ignition on, and hear the carb vent solenoid click once. pump and filter are underneath the car behind the drivers seat. hope this helps, good luck!

 

welcome to the board.

here's a link to the FSM: Foxed.ca

if it fired when you put gas directly into the carburetor, then i can agree you're probably looking at fuel supply issue. as stated above, when you turn the key to ON (not start), you should hear the pump come on. if it does, then pull the line at the carb inlet and test the supply per the instructions. if it does not come on, then check the fuse and then the relay, if either of them are bad, then replace. if they prove to be good, then you may want to remove and "bench test" the pump.

a quick note though, if the car was sitting a while, then there may be issues with rust and/or other crud in the tank. also, the gas itself may be bad. it might not hurt to drain the tank and put some fresh fuel in, and also change the filter on GP.

 

So by jumping the fuel pump relay, I was able to get the car to start up but it doesn't want to stay running. it will start up and if I give it some gas it will stay running around 2000rpm, yet as soon as I let off the gas it will dies. and it like a smoke show out of the exhaust when I first started it but after trying to kept it running a couple of times the smoke was gone.

 

is it hot or cold when it's behaving like you described?

 

it would be a cold start.

 

Remove the fuel supply hose off the carb and put into a jug. Crank and see how much fuel is being supplied. There is a procedure in the Factory Service Manual which can be found here: Foxed.ca

Also a good time to do a compression test.

 

does your choke work?

at any rate, run it until it gets up to temp and see what it does then. could be a simple matter (like a vacuum leak or adjusting the carburetor), or it could be something more complicated.

 

I removed the fuel line that go to the carburetor and this was the gas that came out from. and I was able to do a compression test and the results from it wasn't the best. I was getting 70psi on the front and around 58psi on the rear rotor. but I plan on removing the old gas from the tank and putting in new gas and adjusting the idle screw to at least have it idle without me giving it gas with the pedal to kept it running.

 

Did you time how long you ran the fuel pump, and measure the volume of gas collected?

 

The fuel pressure should be close to 3.5 PSI and the volume test shout yield 1400cc or more per minutes. You should be able to cut the time down proportionately.