A little while back I took my 1990 FC N/A to my local mechanic who was referred to me by the Mazda dealership because he used to work there when FCs were current. I had him check out the car when I first bought it and he mentioned that the timing was wrong.

I just got around to using a timing light to correct the timing on my FC and it feels better than ever but when my mechanic told me the process it was going to take to correct the timing, he described a process which involved taking off the pulleys and adjusting them. I was able to get the timing dead on with the light by just adjusting the CAS and not touching the pulleys.

My question is - even though I have the timing light telling me that my timing is dead on for leading and trailing, is there more steps to be taken to guarantee that my timing is absolutely correct by adjusting pulleys or do I just trust the light and my CAS adjustment?

 

Your mechanic is full of it. Why in the world would you remove pulleys to adjust them? They are either keyed (crank pulley) or just spin in circles?? Yeah he must of worked at the Mazda dealership when FC's were current, but probably never touched one.

To set your timing, you need to jump the initial set connector to ground (look in drivers side area, near battery for SINGLE GREEN PLUG, ground that sucker). When you do this the idle may drop down.

Set your idle speed to 750rpm using the screw on top of the throttle body (usally covered by black cap) and then check timing with timing light. Check trailing side (RED) and leading (yellow) and adjust with CAS to get them right on the line with the pulley.

Remove jumper cable from initial set coupler. You are set.

While doing all this, I suggest you adjust your TPS to 1v before you set idle and check timing. All this done with initial set coupler grounded.

 

Thanks, I had a feeling he lost it too, with RX-7s it always good to do the mechanic check on rx7club you never know what they are going to make up.

I did not jump the initial set connector initially so I will redo my work tomorrow.

 

I'm going to give him the benefit of the doubt. Maybe you didn't completely pick up on what he was saying. Either way, as long as you have the correct pulley and hub you just have to get the pointer lined up to the leading mark. Follow the factory service procedure exactly.