Climate Control problem revisited

[scottmo@tekig5.pen.tek.com (Scott John Mockry)]

A couple of months ago I reported a problem with my climate control system
in my 86 5000 CST. Occasionally with the system in ECON with the temp set
to around 65 degrees the system would blow warm air out the center vents even
though the outside temp was 65 to 70 degrees. Well, the Blower motor
quit running so while I had the blower housing out (what fun!) I decided
to replace the Bowden cable that goes from the programmer electric motor
to the housing flaps. The cable operation was a little stiff and I was
hoping it was the cause of the warm air problem. I noticed the motor lever
would be in the middle position (should be all the way to the left) when
the problem occurred. The programmer is located behind the glove box. While
raising and lowering the temp I noticed that I could stall the electric motor
by placing my finger on the output shaft. I pulled the motor out of the
programmer and removed the end cap where the two wires come out of it. The
motor uses tiny metal fingers for brushes and these fingers had metal crud
on them. I carefully cleaned the brushes and commutator and reassembled the
motor. Now the motor runs strong and the lever moves reliably back and forth.
The bently manual states the early 5000 (84-85) cars had a weaker motor that
can be upgraded. Import Parts Connection (IPC) in Fresno, CA (1-800-472-1144)
does carry the electric motor for about $65. IPC has an extensive catalog
($10) for the 5000 cars with reasonable prices. I purchased a new OEM
Bosch blower motor for $115 versus $175 at the dealer. Hope this info is
useful.
Scott M.