Crank pulley

[Zithlord]

Can someone explain the markings on the crank pulley for me? I have marked the notches with the red arrows. I think it says Z1 at one of the notches, then there are two notches just 5mm apart and two other notches by them selves. There is also a letter or something marked with a "?", because I am not able to read it. I need to be sure for setting timing etc. Is the Z1 mark TDC?

Engine is a 71 2,2S

Thanks
John

[Zithlord]

Found this drawing, seems like the 5 degree ATC is not marked with a notch on my pulley?

Should this engine be set at idle 900 RPM, warm engine at 5 degree ATC and at 35 degree at 6000 RPM?

John

[HarryD]

John,

It is my understanding that the 6000 rpm timing is more critical than the idle timing. That said, you need to verify that the advance moves smoothly as well when you increase the rpms.

When you set you timing at 6000 rpm, wear hearing protection and be sure your tie is not hanging down into the engine room.

[911quest]

Z1 is TDC the other marks that are 120 degrees off from Z1 are for adjusting the valves..

[Zithlord]

Thanks, then both the MFI and dizzy have been installed correctly....now I just have to wait for the chassis(middle of July) and install the engine, then fine tune the ignition timing and dwell.

John

[Merv]

Found this drawing, seems like the 5 degree ATC is not marked with a notch on my pulley?

Should this engine be set at idle 900 RPM, warm engine at 5 degree ATC and at 35 degree at 6000 RPM?

John

Thanks - this one of the most helpful posts I have found with the diagram of the crank pulley markings.

Merv

[edmayo]

Something that wasn't explained is that the pulley diagram shown in post #2 above is for 72 and later engines with a vacuum retard that was set retarded at idle. The pulley shown in post #1 is for engines up to 71 that had no vacuum retard, therefore there is no 5 degree retard mark on the pulley.

[goodtogo]

For anyone who has tried to set their own timing, this thread is great.

I have been trying to find a picture that matches the pulley on my 1971 t engine and the closest match I can find is the picture in post #1

Mine is pretty similar, although it has an extra mark on the pulley, going anti clockwise to Z1 (ATDC) and the same distance from Z1 as the two 30 & 35 degrees clockwise from Z1 (BTDC).

A couple of extra observations are: That the Z1 & 30 & 35 degree timing marks go right across the pulley i.e. they are stamped on both outer and inner flanges of the pulley, but my mystery mark and the two valve timing marks are only stamped on the outer flange (if that makes sense).

Also, the two large holes in the body of my pulley are the same as in picture #1, i.e. in a vertical line from the Z1 mark on the flange, not offset as in picture #2. My engine has the Marelli Distributor (no vacuum retard), hence no ATDC retard mark ( many thanks Ed Mayo, this now makes perfect sense).