[TR] Push or pull

[Chris Kantarjiev]

> No one has mentioned a thermostatic fan clutch, which would offer some 
> of the horsepower-savings of an electric fan without the wiring and 
> fabrication hassles. Does anyone have experience with one on a Triumph?

On both my GT6+ and TR4A, yes.

The GT6+ has a fancy one with a remote thermocouple and and adjustment 
pot, as well as facility for sensing when the a/c is on and an external 
override. I mounted the thermocouple at the bottom of the radiator and 
ran a small toggle to the side of the dash for the override. The toggle 
is a lighted unit; I don't remember the details at the moment but was 
able to arrange things such that the light comes on whenever the fan is 
running.

I set the adjustment such that the fan comes on when the bottom of the 
radiator is about 185 degF; at that point, the radiator needs help.

This has been a fairly successful install. I started with a 12" pusher, 
but found that the fan would come on in cool weather while cruising on 
the freeway! I decided that the fan was blocking too much of the natural 
through-flow, and moved to a puller. I managed to mount a 10" puller, 
slightly off-center to clear the crank pulley, and it's not really quite 
big enough for hot weather since I shaved the head a bit. I'll be 
researching thinner/more efficient fans soon.

The TR4A is a much simpler install. The thermocouple is a fixed-temp 
unit, inserted in the ground lead, mounted to the radiator with a couple 
of stainless "nails" that go through the core. By (tedious) raising and 
lowering the mounting point, I was able to get the fan to come on when 
the temp guage reads about 75 degC (a bit right of center).

The fan there is a puller, mounted to the suspension cross bar with U 
bolts. This is easy, but the shroud is not in contact with the core, so 
some (much?) of the fan's capacity is wasted. I'll eventually revisit 
this and add mounting tabs to the radiator frame.

Best,
chris