If you examine the tensioner bore and foot closely you will find in addition
to the spring, there are two opposing check valves. The spring should do
what you all have been talking about, keep enough tension on the chain to
keep it on the sprockets and off the evil-L. Once the oil pressure comes up,
it supplies the tension. As for the hole in the foot, the check valve must
leak a little to lube the chain and allow the oil pressure to bleed off as
the engine cools down (chain gets shorter, would probable break if some
tension was not released). There is a former roadster owner locally that
made a mechanical replacement for the upper tensioner, but this guy has a
*complete* machine shop (restores motorcycles), I don't think it's feasible
to duplicate -- Ken Pletcher may know more about this. BTW, things could be
worse the old 911's had chain tensioner that would fail without warning at
any mileage, if you were lucky all you needed was a $350 tensioner... A
friend of mine makes a slick mechanical replacement -- if part get real
scarce he may be able to design a similar replacement for the roadster.
Todd Osborn
San Jose, CA
----- Original Message -----
...
> All this talk about the spring and shims got me curious so I took my new
> tensioner and checked it out. The spring that comes with it doesn't seem
> that spectacular to me, and there is a hole right in the middle of the
> rubber pad.
>
> Here is a pic of the device and the spring.
>
> Andrew Murphy
> 67 2000 Solex
> SoCalROC
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