George :
The springs are supposed to be different on a TR3. In fact, the stiffer
of the two springs is actually supposed to be loose at full retard, it
doesn't come tight until 8-10 degrees of advance. Because of that, and
the very low speed where advance starts, I wouldn't expect the rotor to
'snap back smartly'. In fact, with silicone grease on the rub and pivot
points, mine doesn't actually return all the way by itself.
The book recommends lubricating the weights with 20w motor oil, both
when reassembling the dizzy and every 6000 miles. (That's the two drops
of oil you are supposed to put under the rotor. It gradually works it's
way under the screw head, down the inside of the point cam, and out onto
the weights and springs.)
The only way to check the springs is to watch them in action. This can
be done by either taking the dizzy to a shop with a machine, or by using
a timing light on the car. If you use a timing light, you can either
get the fancy electronic ones with an advance control, or you can simply
put timing marks on the rim of the lower pulley. Since the pulley is
5.5" diameter, every 1/4" is 5.2 degrees. The factory book gives the
curve as :
rpm advance (decelerating)
200 0 - 2
600 6.5 - 9
750 8.5 - 10.5
2000 12.5 - 14.5
2700 13 - 15
Randall
George Hahn wrote:
>
> In trying diagnose a sporadic (ignition?) problem I found the return
> springs on the centrifugal advance weights to be pathetic. Since they
> are not identical I assume at least one is incorrect, in any case, both
> seemed to have little effect.
>
> Am I correct in recalling that the rotor should snap back smartly when
> you move it by hand to the advanced position then release it?
>
> In addition to renewing the springs, should the various places where
> they mount & rub the action plate be lightly lubricated? TIA.
>
> Geo Hahn
> 59 TR3A
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