RE: Tranny removal

[Tim Buja <buja@domain.elided>]

Chris Fereday wrote
>...I test drove a STAG auto at the weekend. The car is amazingly sound
> (structurally speaking), but I am a bot concerned about the auto box.
> It seemed to stay in 2nd for a long time (up to 4,000rpm) when cruising.
> Is this normal?

You may need to adjust the downshift cable at the carb pedestal.  See
procedure 44.30.01 in the Repair Operations Manual.  An incorrectly
adjusted downshift cable will affect the upshift speed point at high
rpms as well as the downshift quality as you come to a stop since it
affects the internal hydraulic control pressure in the transmission.
Generally speaking, lengthening the outer cable will make the
transmission "think" your throttle is open more (an increased load
needs a higher upshift speed), while shortening the outer cable will
make the transmission "think" your throttle is open less, resulting
in a lower upshift speed.  You may have to tweak the cable position
several times to get a good compromise between high and low rpm
shift points.

> Selecting Drive or reverse was met by a bit of a 'clunk'.

Idle rpm set too high (above 900-1000 in neutral or park) will give
you a loud clunk when you initially select a gear.  Try adjusting the
idle rpm down to 800 or so and see if it makes a difference.  I've
heard that the BW35 likes a 700 rpm idle speed, but it's rare to see
engines that will reliably idle at that speed.
 
> Changing from 2nd to 1st (kick down) resulted in a 'wheel spin' effect
> from the gear box (not the rear wheels), before the gear engaged.
> Any ideas? Also, does anyone know how much to get the box refurbished /
> replaced if it is 'knackered'? 

Sorry, can't help you here.

If you want more information on how automatic transmissions work, point
your web browser to:
http://www.thegrid.net/thedrivetrainpage
There a couple of interesting articles on how the hydraulic pressures
do the shifting for you, and how the downshift cable affects the
internal control pressures to change the shift points at high and low
rpm.  Most of the specific repair examples given at the site are
directed toward American (GM, Ford, Chrysler) automatic gearboxes, but
the general theory will still apply to the BW35.

Tim Buja - Rockford, Illinois, USA - 80 TR8, 73 Stag, 72 TR6