I have 2 mazda RX7 one is an 86 Gxl and the other one is an 87 the base model i guess (SE). The motor went bad in the 87 one so i got the gxl with a bad trany but its got a new motor (only 40K). So i decided to do an engine swap. First i didnt know if the Gxl engine would work on a base model. Anyways i did the engine swap and i put everything together the right way but its not working. It turnes over but it doesnt start (a mechanic said that its got no spark) Its been in the shop for more than 7 months and noone can figure out whats wrong. If anyone there has the same problem or knows how to fix it please let me know. I really want to drive my RX7 again. Thank you.

im doing what your doing but reverse a base motor into a sport. I hope everything goes good except for the fact I droped a nut in the EGR port.

Well, you need 3 basic things to start -

1. Spark

2. Fuel in the right ratio

3. Compression



Take the spark plugs out and inspect them. If they are noticeably wet, you probably have it flooded. Verify spark by putting the plug (CLEAN AND DRY ONLY) in each of the four plug wires in turn and have someone crank the motor while you ground the plug to something like a strut tower bolt or other good clean rust and paint free metal spot (You might want to use a pair of insulated pliers to hold it - otherwise you may get a jolt). If you have no spark you may have a bad coil pack BUT it might just be a bad plug, so be sure to try another plug.



Check the rotor compression on both rotors.



Verify the timing is correct. If the Crank Angle Sensor was installed incorrectly, it will could be very difficult to start. Remember fuel at the right ratio, spark at the right time, and good compression.



If you have spark but the plugs were wet, clean them with some carb cleaner and dry them. Put them back in and unplug the fuel pump connector (located on the rear driver's side strut tower), crank the motor and see if it tries to start. If it does, plug the fuel pump back in and try again. Ideally you will get the pump plugged back in just before it runs out of gas. This may take a few tries.





Good Luck!