When I replaced my camshaft with a reground one from BPNW some 5 years ago,
I had to return 2 that had too much end float. After the second bad one,
they checked the ones on the shelf and only found one good one! After
dealing with me, they instructed their machinist to regrind that section
too. My theory on this is that if grime gets up there, it isn't going to
be washed out to be filtered clean. Instead it gradually grinds away
material. I thought about getting a special plate made, but I had recourse
with the supplier. Whatever you do, get it right. Good luck.
Bob Kramer, Austin TX
Hill Country Triumph Club
TR6x3, TR250 x3, TR3A vintage race
rgk@flash.net
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> From: Gary & Priscilla Klein <gklein@erols.com>
> To: triumphs@autox.team.net
> Subject: TR-6 Camshaft Problem
> Date: Wednesday, August 06, 1997 7:43 PM
>
> Fellow Scions,
>
> I 've started to reassemble my TR6 engine after a tear-down to rebuild
> the bottom end. The block, crankshaft and rods were reworked [new
> pistons (.020 over), mains (.010 over), big and small ends too]. The
> cam lobes look fine (no pitting) and all measure within tolerance wrt
> lift. The journals diameters were within spec as well.
>
> My problem: excessive cam end float.
>
> Upon reasseambly, I measure .018" of cam end float. Bentley's states
> that .004 - .008 is spec and that a new cam keeper should be used to
> bring the float back within spec. I neglected to buy a new keeper when
> I purchased my other engine parts, however, I measure only .003" of wear
> on the old keeper which will not bring the float back to within spec. I
> then examined the groove in the cam in which the keeper rides and
> noticed that the while the rear most edge is perpendicular to the cam's
> axis, the front edge is perpendicular for the same depth that the keeper
> comes into contact with the cam and is beveled from this point down to
> the depth of the cut. Obviously, there has been some wear on the front
> most edge of the cam's journal.
>
> Does this mean a new cam is in order? Any other suggestions would be
> appreciated.
>
> I thought everything was going together too well!
>
> Thanks in advance,
>
> Gary Klein
> '75 TR6
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