In a message dated 19/07/00 10:19:02 AM Pacific Daylight Time,
owner-mgs-digest@autox.team.net writes:
> Firstly, let me say that I have no experience with ODs. Nor am I an expert
> on oils.> However, have the "no Redline in ODs" lobby considered that MTL
and MT-90 > have friction modifiers to enable the synchromesh to work and
that this
> additive may also help the friction linings in OD units to work?
Simon, synchroniser rings wear when engaging a gear. Better lubrication will
minimise that wear and prolong the useful life of the synchros. It can also
make shifting a little easier, and minimise wear on the gear faces themselves.
OD friction linings are NOT intended to slip, much, any more than clutch
lining is. In other words, yes, there has to be some slip (no one would want
an instant-on clutch), but you do not want to enhance this slippage (which is
what wears the linings) any more than you would want to grease your clutch
before you installed it.
If you DID grease the clutch, it would certainly make the surfaces slip and
preserve the lining, at least until they caught fire, but it would kind of
defeat the whole purpose, don't you think?
The OD friction linings are intended to grab sufficently (and for that matter
to slip an appropriate amount to cushion the engagement) when running in a
bath of regular oil. If you change the oil to one that is more slippery, it
is in a way a bit like oiling your clutch - it may still function, but you
move things closer to the point where you will have problems with slippage.
If you add a more powerful engine and faster competition style shifts that
may not always be as gentle as street practice, you can exceed the friction
limits of the linings, which have been lowered by the new slippery oil. That
is why my friend blew his brand new OD unit. Since switching back to
something like Castrol HD 40, he has experienced no problems at all.
Hope that explains it a bit better.
Bill Spohn
PS - anyone at the Bellevue show in Seattle this weekend, come on over to the
Jensen class and say hello!
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