Tony :
The problem is that, to engage the overdrive, the lever does not open a
valve, but rather closes it. The valve is actually a bypass that bleeds
pressure out of the O/D hydraulic system when the O/D is disengaged. If
the valve does not close fully, then your O/D is operating on less than
normal pressure, which can lead to slippage under load, especially when the
oil is hot. Of course, slippage heats the oil, which increases the
slippage ...
Not a good idea, IMO.
If you really want to reduce the operating pressure, there is an adjustment
(at least on the early A-types) to do so. It is not dependent (much) on
oil viscosity and so is temperature independent.
Everything I've read on automatic transmissions (which bear at least some
resemblance to our O/D boxes <g>) suggests that fast clutch engagement
reduces wear. (as long as the other components can stand the strain <g>)
Randall
On Wednesday, March 03, 1999 5:07 PM, Tony Rhodes
[SMTP:ARhodes@compuserve.com] wrote:
>
> >I certainly wouldn't try to soften the shift by adjusting the lever arm.
> > The only way it would work is if you either slow down the movement,
which
> >will likely burn up the solenoid, or make the valve leak when the lever
is
> >in the engaged position, which will eventually make the O/D slip.<
>
> Slowing the movement of the arm is not necessary. My understanding
> of the adjustment is that you adjust the arm so it opens the actuating
valve
> just a crack. This way the hydraulic pressure in the OD builds up more
slowly
> allowing a litttle more clutch slip and more gradual OD engagement. It
seems
> that this is a fairly critical adjustment and has to be adjusted slightly
and
> then tested. I think that the OD engaging with a "bang" is tougher on
the
> system than letting it engage more slowly. De-clutching is not necessary
with
> the proper adjustment.
>
> I must say that mine is not yet adjusted to the optimum, and I also
prefer
> to de-clutch than let it hit hard.....
>
> -Tony
> http://ourworld.compuserve.com/homepages/arhodes
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