Hi Rob :
Susan Blubaugh wrote:
>
> I have also discovered what I had expected in my #3 cylinder ... a bad
> exhaust valve. It is not broken but it appears to have slight straight edge
> to it where it should be round. There is no more "edge" missing than the
> thickness of a small screwdriver for about 45 degrees of the full circle of
> the valve edge. The valve does seem to be searting deeper than the others.
> Probably the seat is gone. Could this slight bit of visual damage account
> for a cylinder compression drop from 180 psi to about 70 psi??
Yes, definitely. Most likely, the guide is now shot too. The good news
is that parts (including hardened exhaust seats for unleaded gas) are
readily available, and your local machine shop should be able to install
them. Check the valve springs carefully (or just replace them), since
weak springs can cause burnt valves. If you decide to change all the
exhaust valves and guides, you might consider going to TR4A valves,
using the 'conversion' valve guides.
> Does anyone have advice or recommendations of the best source for liners,
> pistons, rings, crankshaft bearings, etc.?? (TRF, Vicky Britt, Moss?)
I have heard bad things about the liners that VB sells, basically poor
quality control. You may get a good set, or not. Either TRF or Moss
should be fine.
> A
> local machinst that everyone trusts and respects has told me that he has no
> experience with wet sleeve engines. Should I shop around and find someone
> who has this kind of experience? (Do such people exist?)
Such people do exist, but not around Rensselaer ! If you are planning
on replacing the pistons and liners anyway, then I would say wet liner
experience isn't necessary. Show your mechanic the section in your
manual about installing the liners and clamping them in place, after
that there's no real difference.
Randall - ex-Rensselaer resident
59 TR3A daily driver
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