Dave :
Some rotational motion of the cam is normal, I'd say a total of 45
degrees movement isn't unreasonable. This is not only the motion of the
centrifugal advance, but also lash in 3 or 4 places (dizzy to drive
gear, drive gear to cam, etc.)
However, 45 degrees either way, for a total of 90 degrees, sounds
excessive and should be investigated.
Ignition timing can certainly cause lack of power and sluggishness. I'd
suggest a timing light and Mityvac to check out both the centrifugal and
vacuum advance while the engine is running. Using the light, you should
be able to see the timing mark advance smoothly as you rev the engine to
about 3000 rpm, then retard smoothly as you let the speed down. A
'jumpy' mark or a lack of movement indicates a problem. Look for the
same thing as you apply vacuum to the advance. (The motion stops at a
fairly low amount of vacuum, don't recall offhand how much.)
Since you didn't mention it, I'll point out the obvious : you must reset
the timing after adjusting the point gap. Since the advance curve on a
TR3 starts below idle speed, it's difficult to use a timing light to set
the initial timing, the static method gives more consistent results. I
generally just use the 'road test' method given in the book. (Hot
engine, 4th gear, heavy throttle from 30 mph to 50 mph, a small amount
of "pinking" should be just barely audible. I like to back off another
10 clicks or so from there.)
Randall
59 TR3A
Dave Willner wrote:
>
> I gave my TR3 a lite tune up yesterday, cap, points, condensor, rotor, etc.
> and while adjusting the points it seems the cam on the distributor developed
> some play and I couldn't recall if this is normal not, seems to me it's not.
> I can freely turn the cam about 45 degrees either way till it stops. I took
> the plates off and things looked ok inside, then tried all the old parts
> (car ran very well prior). Reassembled the car runs at about 75%, lacks its
> normal quick and responsive accleration mostly, feels real sluggish and
> lacks top end power.
>
> Any thoughts here. TIA
>
> Dave Willner
> 59 TR3A
> 70 BSA 441 Victor Special
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