I just purchased a 2ND gen Mazda RX-7. I got it not running but the engine looks completely stock. It cranks over it has spark and has compression and it's getting fuel, but it just won't start. I've checked all the fuses all the fuses are good but one, the room fuse. Everytime I try to put a new fuse in it blows right away. I have tried finding the short and have not had any luck. Would the room fuse cause it to not start?

 

It would not cause the car to not start. Room fuse powers the alarm, radio, idiot lights, key ignition reminder and ECU.

Does the car run on starter fluid? How did you test the engine was getting fuel?

 

When I pulled the plugs there was fuel on them. I'm getting strong spark spark. As far as starting fluid no it doesn't run on it. It back fired once with it but that's it, I'm guessing timing? But ive gone over that. And when it cranks over the vapor from the compression comes out the tail pipes. Is it possible the crank angle sensor is bad? I just need a rx7 buddy who can come over for pizza and beer ahaha.

 

If the CAS was bad you shouldn't be getting both spark and fuel. How about deflooding the engine/clean up the plugs. And the engine should at least fire up very briefly w/the starter fluid so that's a head scratcher. What are your compression numbers. Does the tach needle bump w/key to start?

 

I have not done any actual compression test yet. But it sounds strong coming up at tail pipes when you crank it over. I am running errands today so I will go ahead and rent one from AutoZone or O'Reilly so I can actually see what's going on but until then I will give that other suggestion a shot thankS

 

I just took out the plugs clean them deflooded the engine and crank it over with starting fluid and I didn't get anything. As far as the tack yes it does move and wiggle when the engine is turning over.

 

You need to try a compression test as it will give you a heads up on what is going on.

 

I just tested my coils the book says resistance should be from 0.2 to 1 ohm, I tested 1.4 ohms on the leading coil and 1.5 ohms on the trailing coils, would them being off that much cause the car not to run??

 

Not really sure on that but if it sparks it sparks and the spark should be blue (strongest) and orange/red (weakest). Until you take a compression test you're just guessing to this point.

 

I should have known... it sounded really really quiet when I first turned it over when I was buying it... i ran a compression test on both cylinders. The neddle didnt move an inch.. i hope that means somthing. Especially since he did a metering oil pump delete on it . Maybe he forgot to plug one of the oil injector holes? Thid sucks. Idk what to do, it would be a great 86 302 ford Motor swap and fast because its nice and simple. Only I need a running car lol. I can do it tho. Any suggestions whether it's motor swap, motor rebuild, junkyard engine, crate motor. Thank your for all of you help. Much appreciated

 

Compression Check

And it's possible that the apex seals are stuck (there are ways of trying to unstick them using mmo).

 

Mmo? If you have any suggestions on how to unstick them that would be greatly appreciated. And if anyone could direct me to a rebuild kit for this motor that would be much appreciated as well

 

Marvel Mystery oil.

Atkins Rotary and Mazdatrix would have rebuild kits available.

 

Before you run off half cocked and assume the engine is blown do a PROPER compression test.

If you think plopping a 302 in the engine bay is a piece of cake then you are in for a big surprise.
It's more than engine placement.It's fuel supply,exhaust routing,electrical hook up,Rad and hose routing....and the list is just starting.
I know..it's still in the garage.

 

I already did a proper compression test ( with a compression tester gauge and putting your thumb Over the Hole and having no pressure at all) it came back completely zero. And the motor is already out and from what I can see I'm only going to have to buy or modify an oil pan motor mounts are no problem. And as far as the wiring I already have everything I need and all the wiring to do a whole new wiring harness and the fuel tank has to be cleaned and reinstalled because I'm going to just use the original fuel tank. And if I blow up the rear center section then I have an 8.8 posi rear end to put in it.

 

Well..you got your work cut out for ya so I wish you the best.
*hint..302 double sump oil pan fits over the Granny's cradle..
Make sure that the steering rack lines do not get pinched.

 

a rebuild is cheaper than dropping in a 302. Stop being a lil girl rip that engine out and start learning about your own car with the info on the internet there's no excuse for people not to be able to learn anything aside from laziness or disinterest. If it's the latter then a rotary isn't for you. Best of luck

 

Yeah, be a man and rebuild it.

 

Considering I bought this vehicle to be a daily driver. I cancelled my V8 swap and went ahead and purchased a motor from a junkyard with good/ok compression 100 PSI in rotor 2 110 PSI in rotor one. Assuming it has been sitting for a few years is there anything I should lubricate the motor with beforehand prior to starting it to save the apex seals? Any tips on first start up? And I am saving my old motor for a rebuild in the future.