bowman
Respectable
I have a 1975 450SE and my old vacuum advance can (987 on arm) has a ripped diaphragm. I got another one that would physically fit in the space on the distributor but the arm is longer (It says 2781).
After trying this new one, I can't get the timing set correctly because the arm is longer than the original so it is rotating my base plate too far counter-clockwise at rest. I tried to compensate for this with base timing settings but I think either the spring tension is different or the simple geometry of the new set-up is throwing the swing off so I am in the weeds.
I can't find a direct replacement of my can ANYWHERE and wondered if anyone could give me advice or has a cross-reference chart with how I can source a replacement using just those last 3 numbers 987. This is frustrating because I have done a load of work to the car, this is the final piece of the puzzle and I am coming up short.
After trying this new one, I can't get the timing set correctly because the arm is longer than the original so it is rotating my base plate too far counter-clockwise at rest. I tried to compensate for this with base timing settings but I think either the spring tension is different or the simple geometry of the new set-up is throwing the swing off so I am in the weeds.
I can't find a direct replacement of my can ANYWHERE and wondered if anyone could give me advice or has a cross-reference chart with how I can source a replacement using just those last 3 numbers 987. This is frustrating because I have done a load of work to the car, this is the final piece of the puzzle and I am coming up short.
