TR2/3/3A TR3 Electric Fan/Reg Fan

[mountainman]

How many of you that has installed an electric fan kept the old manual fan and fan hub on the car? I would like to add an electric fan to my TR3 and remove the old one with the hub. Someone mentioned that removing the old fan and hub can cause the crank shaft to break. Could someone advise me on what to do.
Thanks
Greg

 

[NutmegCT]

Looks like there are several sets of opinions on this. One refers to needing the electric fan only when the engine is idling.

https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/618248/

And to whether the electric should "push" or "pull" the air.

Also, some folks keep the original, and some don't:

https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/533959/

Hope this helps.
Tom

 

[Don Elliott]

I have a 12" electric fan (Kenlowe from UK) as a "pusher" in front of my rad and I kept the original fan for the VTR and TRA judges. It works very well. I flick a switch under the dash to turn it on and off. I mounted it above the hole for the hand crank and I can still start my 1958 TR3A with the crank.

 

[JohnB]

I seem to remember reading somewhere that the hub and original fan act as a sort of harmonic balancer for the crank and helps prevent possible breakage.

Any one else heard that?

 

[TR3driver]

Any one else heard that?

Yup, I've heard it too, from people who should know (eg Kas Kastner). One of our local vintage racers even brought a rear main journal to "show and tell" (they snap just in front of the rear main).

But apparently the problem only shows up when the engine is run at a particular constant rpm well beyond factory redline (eg around 5200 rpm) for long periods of time; and even then is only a problem for a relatively small number of engines. I suspect the problem can be characterized more as a metal fatigue problem (ie takes a long time to actually break) than an immediate "do this and it snaps".

I've covered well over 100,000 miles with the same stock crank and no fan, fan extension or dampener (including some long periods around 4500 rpm), and never had a problem. Still, I plan to use a dampener on the "hot rod" motor, just to be safe.

 

[DNK]

Don you have an electric fan and still win all those awards.
Oh the humanity

 

[Geo Hahn]

I have a 12" electric fan (Kenlowe from UK) as a "pusher" in front of my rad and I kept the original fan for the VTR and TRA judges...

I have a similar set-up, in my case I mounted it a bit lower but such that I can still use the hand crank -- inserting the crank just pushes the blade out of the way.

The pusher arrangement is likely less than ideal but I find it adequate for a 'helper' fan in Tucson summer traffic or drives up our mountain.

 

[prb51]

I went to Kastners site and asked the balancer/harmonics question...everyone that races said "drop the lump".
I've had both pushers/pullers and both work well.
No fan, extension etc. now and I drive it hard.

 

[deadair]

I went to Kastners site and asked the balancer/harmonics question...everyone that races said "drop the lump".
I've had both pushers/pullers and both work well.
No fan, extension etc. now and I drive it hard.

What does "drop the lump" mean?

 

[Don Elliott]

Don Kelly and George Hahn

For TRA in 1992 and 1996, I removed the front bumper, the grille and wires, un-bolted the fan and stuffed the feed wire up out of sight. There, they didn't remove any points. After the show, I'd still be there on the show field for an hour putting it back into place.

But then I thought to myself that the judges would have to get down on their hands and knees to peer at a black Kenlowe fan in a black painted area with a black radiator and what they found out was that the knees of their pants got scruffy on the dirty asphalt or they got grass stains if the concours was held on the grass. I believe they can't see very well or they don't bother to check. I leave it on now and I can't say that I ever got points removed because of the pusher fan "hidden" behind the grille of my 1958 TR3A.

My fan has 10 blades if you go back up and look at the photo and the hand-crank might have a bit of trouble to get through the space available because the outer ring shroud keeps it all pretty rigid. I could try, but it's been like this for 18 years so why bother. But I have to admit that it's a good idea.

 

[bgbassplyr]

I went to Kastners site and asked the balancer/harmonics question...everyone that races said "drop the lump".
I've had both pushers/pullers and both work well.
No fan, extension etc. now and I drive it hard.

What does "drop the lump" mean?

Remove the hub and fan.

 

[vivdownunder]

My electric fan looks to be identical to Don's, only mounted a bit lower down. The starter handle fits inside the rim between blades.

From memory I think it was originally a Range Rover fitment when I purchased it in about 1995.

The key to a pusher fan not impeding airflow to the radiator is to select one with thin blades.

Viv.