'83 SC timing marks

[hughc]

The Bentley manual makes reference to the TDC mark on the flywheel pulley as Z1.
There is a single mark on my flywheel pulley which I assume is TDC but I cannot see a Z1 mark on it. Is it the TDC mark?

Also, further along the pulley there are two marks side by side but I cannot find any reference to them in the Bentley manual. What are they indicating?

Thank you,

Hugh

[Bob Kontak]

Originally Posted by hughc

Also, further along the pulley there are two marks side by side but I cannot find any reference to them in the Bentley manual. What are they indicating?

One of the two side by side marks is the Z1 TDC location. Facing the rear of the engine, the one on the right is TDC. The one on the left is 5 ATDC. You should be able to read Z1 on the face of the pulley.

There are two other single marks on the pulley. Each 120 degrees from the Z1 mark.

[Flat6pac]

This is an 83 US that I'm doing right now
Bruce

[Bob Kontak]

Originally Posted by Flat6pac

This is an 83 US that I'm doing right now
Bruce

Thanks for this. The side by side marks are reversed from what I said.

Going to double check. Bet I'm wrong.

[hughc]

Thank you Bob. After carefully checking with a penlight I was able to see the printing that I wasn't able to see previously. Now I know..

Hugh

[Bob Kontak]

Originally Posted by hughc

Thank you Bob. After carefully checking with a penlight I was able to see the printing that I wasn't able to see previously. Now I know..

Hugh

Is it as flat6 says? Backwards from what I said?

Crank pulley moves clockwise. I think 5 BTDC is the timing point at idle with all vacuum lines detatched and plugged. That mark should be first. I got confused by looking at internet pics.

The retard function is the only one that works at idle. Vacuum advance kicks in off idle but that's another thread.

Thanks, Bruce. A pic is worth a million words.

[hughc]

I should have thanked Flat6pac for the photos as they certainly enlightened me, and Bob I think you are correct but I am unable to confirm until I get my CDI unit back from the repair shop.
At that time I should be able to get the SC started up and properly timed.

[Trackrash]

Originally Posted by Flat6pac

This is an 83 US that I'm doing right now
Bruce

The marks on my '78's pulley are the same as this. There were older cars where the marks were reversed.

[Flat6pac]

Yes, the 2.7 used a vacuum retard with an initial -5 then at idle vacuumed the ignition back to about -12 degrees.
Now to properly set up an 80 to 83 you got to know the vacuum connection on the distributor for idle is on the backside of the pod.
Bruce