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TR4/4A Crank shaft pulley for electric fan conversion

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Chasman3

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I isolated the noise that I thought was a water pump by removing the belt on my TR4. It has an electric fan conversion with long neck aluminum radiator. I discovered the crank bolt was finger tight! I took it off and the pulley came off feely. The 1/2 moon woodruff key was in place. But the key way in the pulley is worn giving it side to side movement. I need to replace but don’t know where this conversion would come from? Here is a picture. Any help very much appreciated. Good news crank end is fine. And when I started it to check for noise, wonderful quiet. Just the gentle exhaust rumble and gentle valve train. Thanks again. Charlie
 

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That is a very strange looking pulley, and IMHO not at all suitable, so I would not replace with the same design [even if you can find one].
Appears that someone has welded a spacer onto that pulley, rather than a seperate spacer slipped over the crankshaft end, behind the pulley...That is why it has come adrift...The pulley was probably never fully tight when first installed.
There are probably balancer pulleys available from TR suppliers that are suitable.
On my car, I did a conversion using a specific thickness spacer on the crank and a Aussie Holden dedicated harmonic balancer, whch is an exact fit onto the crank.
 
Agree looks a bit of a bodge. May have been there for years tho.
Could also have been added to
A. Bring the pulley out to line up with water pump and alternator/dynamo
B. Sleeve the front timing cover hole due to oil escape ?

I’d check you usual suppliers for a narrow belt replacement or just go for a new whole narrow belt kit.

But a result on the noise front and even a full pulley kit is a cheap repair for that !
 
malbaby said:
That is a very strange looking pulley, and IMHO not at all suitable, so I would not replace with the same design [even if you can find one].
Appears that someone has welded a spacer onto that pulley, rather than a seperate spacer slipped over the crankshaft end, behind the pulley...That is why it has come adrift...The pulley was probably never fully tight when first installed.
There are probably balancer pulleys available from TR suppliers that are suitable.
On my car, I did a conversion using a specific thickness spacer on the crank and a Aussie Holden dedicated harmonic balancer, whch is an exact fit onto the crank.
Click to expand...
This is the narrow belt conversion made in England and sold by Moss. I ordered a new kit and it came today. It’s just like the old one.

There is a spacer that needs to be pressed onto the harmonic pulley. The instructions call for a soft jaw vise which I don’t have only a regular vise. They recommend taking it to a machine shop for proper fitting if the proper tool isn’t available. Scratched spacer will leak. It’s also tapered.

After that, I think the challenge is insuring the woodruff key does not slip will pushing the pulley onto the crank, even if the woodruff key is dimpled. They also recommend a new timing cover oil seal and gasket which I didn’t order. This is bigger and more complicated job than I thought. But not impossible.
 
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For the pulley to be loose, the spacer must have been too thick...You may have the same problem again....Suggest you take some accurate measurements with the new spacer before fully tightening the crank bolt.
 
malbaby said:
For the pulley to be loose, the spacer must have been too thick...You may have the same problem again....Suggest you take some accurate measurements with the new spacer before fully tightening the crank bolt.
Click to expand...
The pulley was loose because the nut was finger tight. Literally. I unscrewed it with my hand. This caused the damage to the keyway of the pulley. The old woodruff was intact. The damage to the keyway enabled side to side movement of the pulley which resulted in the noise that I heard.
 
I believe oversigh, improper torque and lack of a locking tab washer that is supplied with the new kit. In the instructions it give the 60 foot pounds and references loc tite but cautions for later disassembly (Blue is generally my choice).
 
I had the top Ali narrow belt pulley work loose and the woodruff key way was worn
I used this stuff to secure a new key in the pump shaft key way and let it set then on the pump tapered shaft to secure the pulley to the taper as well as the nyloc nut.
Made for flatter areas of bearing shells so works well on bearing shells and smooth tapers
And don’t do the belt too tight the water pump bearings will thank you.
onlinebearings.co.uk

Loctite 641 Bearing Fit | Online Bearings

Loctite 641 medium strength retaining adhesive
onlinebearings.co.uk onlinebearings.co.uk
 
A soft jaw vise is merely plastic covers that go over your vise hard jaws. Should cost less than $15 for a set.
 
That’s an MGB pulley modified to fit a TR. it’s a common system sold by the usual suspects. I’d replace it with a solid alloy pulley available from the likes of Revington TR among others.
 
Worst case, you can always put the car back stock with the 1 inch belt with a new type tropical fan and you should be good. The original stuff torques down tight. In high school I had a Sunbeam Alpine where the generator flew off at highway speed and did job to the radiator and the generator.

steve
 
I fixed it. Found a fabulous machine shop in Rsntoul, IL. Freshly ground cranks and reworked heads everywhere! Pressed on in a jiffy. I had to lightly file the woodruff and the keyway so the pulley could slide freely onto the crank and woodruff. Second try. I drew it down with bolt. The previous owner didn’t have the locking tab washer and used the thick machined washer upside down. That’s why it came loose. Different car now. Quiet! Next on the list is addressing hood vibration with the short bubble bonnet. The rubber fender supports seem adjusted right but seem hard. But boy oh boy it runs and drives terrific. Thanks for the input. Enjoy the weekend. I know I will!
 
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