Putting a 1985 12a into a 1979 Rx-7

[Zeff]

I have not changed the timing at all. That was something I was thinking off looking at. I also bought new coils. The ignitors seemed to be working. I removed each plug and tested to see if I was getting spark and I was.

Here it is after running for a bit. It wasn't comletely warm yet and will not idle when you unchoke it.

http://youtu.be/PXl4ml-lYqI

[Asiapinball]

Mine sounded exactly the same as this and it was the coil on the leading ignition circuit (rear one). I pulled the spark plugs and noticed they the top trailing plugs were dry but the bottom leading plugs were wet and fouled. Try swapping the coils if you do not have a spare as that sometimes improves situation if leading coil is at fault. Of course it may be elsewhere in the ignition circuit. Good luck. Let us know what it was once fixed. Paul.

[Chud]

Are you 100% that you've got all your trailing and leading the right way round, and for that matter - rotor 1 and 2 the right way? That doesn't even sound like one rotor. Just sounds wrong.

[Asiapinball]

I just read your latest post re getting sparks at each of the plugs so not likely the fault. As you state ignition timing is next to check. Paul

[Asiapinball]

As I have just been working on mine. Trailing coil is front coil and should have blue lead and go to socket on outside of distributor cap. Leading coil is rear one and should go to middle sockets on distributor. Top plugs are trailing and bottom ones leading. Front rotor is 1 and rear is 2. Distributor cap should be marked for east identification. Paul

[Zeff]

I think it's more of a carb issue.

http://www.youtube.com/watch?v=FCqBNC0Vcz4

Does that look like the way the fuel should be entering the intake? I more than likely need a rebuild.

Also, this may sound like a joke and I might be out of luck on this but.... when the motor is warmed up and turned off, should I be able to turn the motor by hand? I can turn the e-shaft pulley by hand with out any socket wrench. Am I looking at a no compression engine? It does start well and run well other than the idle.

[RamoNZ]

Any 12a that's done a few miles from new is going to be getting down on comp I reckon but starting by itself hot is a good sign. I'd ignore being able to turn it by hand at this point.

The second video sounds a lot better though.

Very tricky to diagnose over the net though - anything that's been standing so long could have caused untold air fuel spark and compression issues..

[re japi]

I think that some plug is firing wrong... Kind of backfiring... :/ well, dunno for sure...

[Zeff]

OK.. after taking the top of carb off and cleaning air bleeds and jets, it idles now. It will idle all day except not smooth. It jumps around a bit around 1K on the tach. It also runs rough with the choke fully engaged. Driving it on the road its great. Anything over 3K is smooth as silk.

Here is a clip of it idling. It's a bit hard to see but its there. You can see the wires shake a bit.

http://www.youtube.com/watch?v=v-8WIg0e46k

[RamoNZ]

Could be a side seal..?