Ignition timing

[Witt]

Shortly before restoring my Pagoda over the course of the last year, I had the Head rebuilt and gasket changed.   
While driving the car after that work was done, I noticed that the pick up was sluggish and the motor ran on after shutting it off.

Distributor points are fine and correctly adjusted, but the timing was set just to the right of the white paint dot. I always considered   that dot to be the proper timing mark and adjusted the timing to it ( Vacuum hose connected ! ) The car runs much better and the motor does not run on any more.

After closer inspection I discovered that the white dot actually is the zero TDC mark and the timing was set at the proper 8 degrees ATC as I learned from the manual.

So I am running the car with the timing at TDC now and its running better than ever. Temperature and oil pressure are not affected, but I had to turn the idle back to about 750 RPM via the air screw. The idle adjustment on the IP is already all the way leaned out before I started fiddling.

Question: Is this OK  ?

PS: I am a retired mechanic, had my own shop fixing older VWs. I do most of the work myself and I know and trust the mechanic, a former college, that did the head work.

CHEERS !
WITT !

[ja17]

Hello Witt,

Did you check the timing at 3,000 rpms? Sometimes a distributor problem, defective timing or vacuum relays may alter idle timing. Setting the timing at30* at 3,000 rpms will be a good check.

If you  have the mixture idle screw all the way lean, most likely the fuel mixture is a rich at the other speed ranges. 

Try a split linkage CO test at 2,000 and 3,000 RPMs to see what the mixture is like at these ranges.

Also, if your car is an automatic, drastic changes in timing can also change engine vacuum and shift characteristics of the transmission.

[glenn]

Witt, If you are controlling idle speed with 'reduced' idle air, you are probably running rich.  Do JA's linkage disconnect.  Reduce idle fuel(FIP knob), adjust idle air to max RPM, repeat until you get 800 RPM, then cut back idle air to 750 RPM - to get 50 rpm of rich.  Glenn

[Witt]

Thanks' for the input, yes the car runs VERRY rich since I got it back. ( Big black marks on the wall when backing into garage, lots of black/gray exhaust when accelerating very hard )
Guess I better check on that first ? !

CHEERS !
WITT !

[ja17]

Hello,

Check the linkages in case the tech altered them.  Next the timing at 3,000 rpms.