Re: TORQUATROL UNIT

[Ann and Tim Buja <buja@domain.elided>]

A number of people have written about the viscous fan coupling lately.
Here's the engineering description from the July 1970 issue of
Automobile Engineer:

"A 13 blade, 16-1/2 in diameter nylon cooling fan is driven directly
from the nose of the crankshaft by means of a Holset viscous type
coupling that limits the torque transmitted to the fan to 46 lbf-in
and the maximum speed to 2,500 rev/min. It is retained axially by a
co-axial bolt: the hub of the coupling, in turn, secures on the
crankshaft a Holset inertia type torsional vibration damper, and two
sprockets for the timing chains; the drive is transmitted to each by
a Woodruff key."

There is no mention of a lockup function as used in many other vehicles
to increase the fan speed when the radiator discharge air exceeds a
certain temperature.

The Torquatrol name is probably developed from the way it functions
by controlling the torque available to turn the fan at speed.

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