Was starting and backfired like a howitzer. Loudest backfire I've ever heard in my life. I've been overseas and it was comparable to the explosions I've been involved in over there. Now it won't come close to starting. Still getting spark and is turning over. Ran dry thinking it was flooded but had no success. Any ideas what it could be?

 

https://www.rx7club.com/naturally-as...-help-1042319/

did you ever remove the CAS? it sounds like it could be a tooth off.

 

I haven't touched the CAS. Tried to check the timing but the main pulley isn't showing any marks... I don't know what past owners have done. Is there a way to estimate where the leading and trailing marks would be on the pulley? I tried wire brushing and wiping with WD40 and a rag but can't find any marks...

 

Shot with the timing light. I chalked the only 'notch' I could somewhat make out on the pulley and this is what I got while on the L1 wire. Is this close enough or should I adjust it. If so how do I adjust the CAS? I can see it has a slot for adjustment but the 'bolt' isn't really a bolt. It's a spinning plastic cap of some sort... Don't wanna touch it until I know for sure how to do it. I'm use to adjusting distributors so this is new to me. It started up somewhat easy today but is still idling funny and popping from the exhaust.

 

Idling in this picture. When it pops from the exhaust the RPMs drop a tad. I had it idling at around 800rpm before but it wouldn't stay running so increased it to 1200rpm.

 

Also want to add. When I rev it to about 3k and let off the gas the RPMs drop right to 0 and it dies... Could that be the TPS?

 

Update.... Got it so it start somewhat easier. Put a toggle switch for the power to the ignition fuse under hood. Turn it over a few times with throttle floored in off position then turn it on while still turning over and throttle floored. Seems to work decent and not as much smoke on start either. When motor is under load the RPMs lower but doesn't stall. I turn on all lights and 4 ways and the RPMs lower more but no stall. It still pops a bit while idling though... Almost like the timing is off a hair... As posted in the pictures I could only find one 'notch' on main pulley... Not sure if it's lead or trailing... Or if it's even a timing mark... Any ideas on how to be certain as the factory paint marks are no longer with us. Haha.

 

well, assuming the CAS is in the right place (or close) you can always use the flywheel TDC reference and then you should have a general idea of where the timing notches "should" be. you can then go back to cleaning the pulley to see if you can find them. between your above photo and the behavior you describe, I still believe it's probably the timing.

also, adjusting the CAS is just like adjusting the distributor. same concept ....