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TR2/3/3A Balancing TR3 Fan Assembly

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Tinkerman

Tinkerman

Darth Vader
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So. I read in the manual that the fan assembly is balanced as an assembly and if you replace any parts it has to be rebalanced on a jig. Any one out there have any idea how to do this?
I have mostly all new parts and a NOS fan blade and one balance piece. Wot to do? Wot to do?

Thanks, Tinkerman the Confused
 
I don't know, But I'd be very intrested in an answer to this one, as I've never gotton one before. I think I have all the balancy bits for mine, but They were taken off before I got the car so I coulden't index them.
Anybody? Anybody?
 
Just taking a stab at this ... how 'bout balancing like you balance a lawn mower blade. Hang on a nail and keep adding or subtracting weight until it doesn't tend to turn by itself.

Tom
 
I would think Tom's method is as good as most (especially since I don't have an alternative one). I think the fan needs to be mounted on the hub extension and you could use the crank/mounting bolt as the "nail". Spin the assembly and theoretically the heavy side will always at the bottom. If the blade pointing down is always random, it should mean that it is balanced.

If there is shop near by that builds drive shafts, they may be able either do the job or give advice.

FYI, after they were balanced at the factory, a small hole was drilled through the fan, hub extension, etc so it could be reassembled. Aligning as many of these holes that you have might be a good starting point.

Don't forget to re use or replace the crank bolt locking plate.
 
You know, I bought a lawnmower balancing device a while back with that in mind. Now it's packed away somewhere, but it was a grey stepped plastic cone set on top of a pin. The idea is to place the blade on it with the cone in the center hole and file off weight until it sits level. Hopefully you can arrange those half-circle balance pieces to make the fan sit flat. I bet you can get one at Home Depot.

Howzit, Dave!

Jeff
74 TR6 CF13816U
 
I thought of that... That's basically the same thing as an old bubble balancer for tires. But a smaller one for mower blades would be better. Good idea
 
Balanced ............. Hmmmmmmmmmmmmmm ............ when I got my TR-3 It had been hit in the nose, bent the bejeebers outta the radiator and fan blade I managed to find a used radiator {this was back in about 1964} anyway ... I had NO idea that this assembly had/needed to be balanced. I took a hammer to the fan blade and reshaped it the best I could and bolted it back on the engine. I`v been running it this way for quite some time now {well at least until I decided to do this last restoration,} In any case I`v ran the engine with the fan in this manner for quite a time and it never seemed to be of any consequence as to the proper running/cooling of the engine.
I had NO idea that it was supposed to be balanced.
Oh well!
My latest plan is to remove both the fan and extension hub completely and use an electric fan setup.
That little four bladed fan never was much to the affect of cooling things off at slow speeds and especialy in traffic stop and go situations.
Hopefuly I won`t run into any S.N.A.F.U.`s In trying to go with electric.
 
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