About a year ago, in my eternal quest for a cooler running Mog, I purchased
from Morgan Spares a six-blade fan to replace the original one. I have been
running tests with it since then and, if you are interested in the results,
read on. If you have one of the new fancy radiators with multiple cooling
rows, you may want to skip the rest of this e-mail since you are probably
quite happy with your engine's temperature.
The fan cost about $70.00. Its six blades have a very aggressive pitch, so
aggressive that Morgan Spares provides you with a spacer that pushes the fan
away from the belt in order to provide the necessary belt-fan clearance.
Installation took a bit of time, but it wasn't a difficult job. I
disconnected the top radiator hose (after draining the coolant) and the two
rods that tie the radiator to the fire wall. I also removed the cross bar
that runs across the cowl. By pushing the radiator slightly forward, I
managed to remove the old fan and replace it with the spacer and the new
fan. All this took me less than an hour. Since all Mogs are different, it
may take you less time (or more?).
My Plus 4 has an electric fan that I set to go on at about 210 F and off at
about 190 F (I have an accurate temperature gauge that flips and hides under
the dash when not needed). I tested the car with the old fan by itself, the
old fan with the electric fan, the new fan by itself, and the new fan with
the electric fan. Yes, perhaps I got carried away, but I guess it's the
scientist in me.
Anyway, there is no question that the new fan makes a discernible difference
in the engine's temperature, both at idle and at speed. I know that when
cruising, the fan should not make a difference since there should be enough
air flowing through the radiator. But this is a Morgan, remember? The new
fan cooled the engine by roughly an additional 10 degrees. Here is a chart
showing what I found:
Air temperature: 84 F plus or minus 2
RPM: 3500 plus or minus 100
Level ground cruising for at least 30 minutes
Old fan only: 212 F
Old fan/electric fan: 205 F
New fan only: 202 F
New fan/electric fan: 195 F
Electric fan only: 208 F
You may wish to know that some time ago I wrote the Morgan factory to ask
for a satisfactory high temperature range for the TR3/4 engine. Their
response was that anywhere between 190 and 226 was OK. The 226 seems a bit
high to me, but I am not one to question them.
So, is there a drawback to the new fan? Yes, without question. It sure
lets you know it's there. It makes a definite whining sound, a bit lower in
pitch than a turbine. At about 3000 rpm, it is quite loud. Is the new
sound worth the extra cooling? I guess you will have to decide that. This
past weekend, at Mog West, I met someone from Washington State that had
installed the fan and then removed it right away because of the noise. As
for me, my electric fan rarely goes on anymore since the new fan usually
keeps the temperature below 210 F unless I'm in really hot weather going
up-hill. So for now, I'll keep it until I install one of the fancy new
radiator core some of you have been talking about.
Armando Picciotto
'63 +4
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