> From: Sumner Weisman <email@example.com>
> To: Ed Woods <firstname.lastname@example.org>
> Subject: Re: Electric Fans in LBCs
> Date: Thursday, June 18, 1998 7:01 PM
> Hi Ed,
> You didn't miss too much. Some folks felt strongly that the standard
> belt-driven fan is perfectly adequate if the radiator is clean and
> Others put larger belt driven fans on with more blades (4 blade TR-4 fan
> instead of 3 blade TR-3 fan), etc. Others felt the current drain of the
> fan was excessive for the LBC wiring system.
> My experience has been very positive. I used to have SERIOUS overheating
> problems with the TR-3, especially when stuck in heavy traffic in the
> summer, and a couple of times it overheated so badly that I was afraid of
> warping the head. I mounted a 12 inch fan on the front of the radiator,
> with its own adjustable thermostat on the fender well. I left the old
> driven fan in there, and the new one just comes on and supplements it
> necessary. Since putting it in, my overheat problem is gone! The
> temperature gage pointer sits on 185 degrees, like it was painted on.
> Never goes above. I love it.
> > From: Ed Woods <email@example.com>
> > To: Sumner Weisman <firstname.lastname@example.org>
> > Subject: Re: Electric Fans in LBCs
> > Date: Thursday, June 18, 1998 9:18 AM
> > Sumner,
> > I wasn't on the list during the fan thread. Could you give me more info
> > what you've installed. I'm going to go that route on the TR3 I've just
> > started on.
> > My '60 is running a TR250 fan, mounted backwards. A bolt on fit that
> > well though I haven't been able to convince anyone that that big
> > plastic fan is original equipment!!
> > Thanks,
> > Ed Woods
> > -----Original Message-----
> > From: Sumner Weisman <email@example.com>
> > To: Triumphs <firstname.lastname@example.org>
> > Date: Thursday, June 18, 1998 8:58 AM
> > Subject: Electric Fans in LBCs
> > >
> > >Hello Listers,
> > >
> > >I am the culprit who started the weeklong thread on electric fans a
> > >of months ago. I certainly don't wish to get into all that again -- I
> > >respect all of your opinions, and have mine as well.
> > >
> > >After a number of off-line conversations with people who want to
> > >one, I thought this note and wiring tip to the list might be helpful.
> > >
> > >I installed a fan with a separate adjustable thermostat. That way,
> > >runs only when it needs to run, after the water temperature exceeds
> > >setting of the thermostat set point. The thermostat also has some
> > >hysteresis, so that it keeps the fan running until the water is cooler
> > >the setpoint temperature. Otherwise, the thermostat contacts would
> > >"chatter" when the setpoint temperature is reached.
> > >
> > >Initially, I wired it to a "hot" circuit that was powered all the
> > >(The fan has its own in-line fuse.) That way, I reasoned, the fan
> > >keep running after I shut the engine down, (like some German cars do)
> > >the engine was cool. That worked as planned, but it ran for such a
> > >time, without the generator charging the battery, that the battery was
> > >always partially discharged. Not a good idea.
> > >
> > >Therefore, I rewired it and connected the hot side to the "switched"
> > >of the ignition switch, so that the fan would not run after the car
> > >shut off. That introduces another possible problem. The fan motor is
> > >inductive load, not resistive. An inductive load, when switch off,
> > >generates an inductive "kick" that tries to keep the current flowing
> > >same direction as before. This inductive "kick" is a large voltage
> > >that can pit the ignition switch contacts. The simplest way to
> > >this problem is to wire, in series with the hot side, a silicon diode.
> > >is wired such that the diode is forward biased when the fan is on.
> > >to power source.) When the large voltage spike occurs (when you turn
> > >the ignition switch) it reverse biases the diode, effectively
> > >the ignition switch from the fan. Problem solved.
> > >
> > >I also wired in a dash-mounted switch to turn on the fan manually, if
> > >needed, in case the thermostat ever failed.
> > >
> > >This system has been in place for over a year with no problems, and I
> > >very satisfied with the results.
> > >
> > >Sumner Weisman
> > >62 TR-3B