Re: 1954 Packard Pacific Oil pressure sending unit 4 way brass tee adapter/ Auburn style dash panel

Posted by HH56 On 2019/11/12 13:42:50

Assuming it is the correct new rotor and you did not turn the distributor in its mount to disturb the timing then I doubt rotor alignment is the issue. The rotor is keyed to the shaft and there is only one way the proper rotor will fit.

I would check that the vacuum advance is working and that the diaphragm did not develop a leak due to old hardened rubber cracking. That has happened to more than one person when bringing a car back to life after a lot of years. You can use a timing light although with the light it might be hard to distinguish between what changes you see to the timing might be from mechanical advance or vacuum advance. Another way is to disconnect the tubing at the carb or other convenient place and use suction from your mouth to see if there is any leakage. A more appropriate test would be to use something like a hand vacuum pump on the line to provide enough vacuum to make sure the advance moves the mechanism.

The centrifugal advance and particularly the weights could also be an issue. Make sure both pivot pins are lubricated and weights are free to pivot and are also securely fastened on the cam. Some distributors need a few drops of oil on a felt in the center of the shaft under the rotor to provide lube to the pivot pins so they don't dry out. Possibly one weight has stuck or one of the small springs used to calibrate and provide the means to keep them pulled in and return them inward when the engine slows has broken.