Auto advance and points cam

[Tom]

Hi all, my auto advance is sticking and seems to be pretty gunky (see pic). I removed the rod to give it a good clean in hopes that it would help before buying new springs etc. Out came the points cam which is quite badly pitted (see pics). Are these chromed? Can it be sanded down slightly to remove the pitting, will it work ok when polished and pitting retained or should i find a replacement/go pamco?

Any other tips?


Cheers!

 

[5twins]

I think I'd replace that one. The points rubbing block rides on that surface and I think it will wear very quickly because it's so rough. If you sand/grind it smooth again, you will most likely change it's size a little and that could throw off the opening and closing times of the points, maybe the amount they open too. Finding a good used replacement should be easy enough what with so many taking them off for a Pamco switch.

 

[Tom]

Cheers mate, thought as much but after inspecting a but more, the highest peaks of the cam are actually clean, it's the lower parts that are pitted. Does that change the ability to fix this one?

I think I'd replace that one. The points rubbing block rides on that surface and I think it will wear very quickly because it's so rough. If you sand/grind it smooth again, you will most likely change it's size a little and that could throw off the opening and closing times of the points, maybe the amount they open too. Finding a good used replacement should be easy enough what with so many taking them off for a Pamco switch.

 

[5twins]

The approach ramp leading to and the exit ramp from the high point would also need to be good. They trigger the initial opening and the closing point of the points set. Try it and see I guess. If the timing is all out of whack after cleaning it, or the points sets wear out quickly, you'll know it's bad.