218 timing

[jchalk1949]

Hi, I just rebuilt a 1949 218 and have a question about timing. Does anyone know if timimg with a timing light, the vaccuum line is capped or hooked up to the distributor? I timed it with it disconnected and after it was hooked up the timing changed. None of my manuals say anything about this. Help.

[Merle Coggins]

Always set your basic timing with the vacuum advance blocked off. If you timing changes when connected that means that your vacuum advance is working. However, your idle may be up too high. It should be connected to ported vacuum which means at true idle there should be no vacuum to your advance unit. Vacuum only goes to the advance unit once the throttle begins to open.

Merle

[48Dodger]

I agree with merle. You could check your timing with the vacum attached since it should be zero at idle. But closing off the line will to the distributor will let you focus on the idle timing, and checking for the best vacum number. I would get the highest vacum from the manifold, then set the idle screw. When your happy with that, then you can move to higher rpms and play with the vacum advance and centrifigal advance. Depending on the quality of fuel and your elevation, you can then move onto retarding the "knocks" out and spark plug reading.

48D

Edited March 15, 2011 by 48dodger

[jchalk1949]

Thanks. Looks like the vacuum gauge is the way to go.