At 07:43 PM 6/13/2000 GMT, Dereck C wrote:
>.... I am putting the freshly machined rocker assembly .... and comment
came out "don't forget to put on the washer" when attaching the rocker
assembly. What washer were they talking about? Could it be the shims? ....
And the answer from the archives was:
There is a small clearance in the pedestals around the shaft, required
to accomodate assembly tolerances, so there is the possibility that the
shaft could move around some in operation causing wear on the shaft and
pedestals. Presumable the thin shims are placed under the #2 and #3
pedestals to take out the clearance and create a slight bending load on the
shaft to prevent any movement of the shaft in the pedestals and thus
eliminate the wear at that location.
Personally I do not use the shims that were not original on my MGA, and I
have not seen this wear problem on either the shaft or pedestals, but
others reportedly have. The rocker shaft will eventually wear at the
rocker arm bushings, probably much faster there than at the pedestals, and
the rocker shaft will likely eventually be replaced. It would be nice
however if you never have to replace the pedestals (which I never have), so
the shims are optional but recommended. (I think I got that right).
Barney Gaylord
1958 MGA with an attitude (and a new rocker shaft every 125K regardless)
http://www.ntsource.com/~barneymg
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