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TR2/3/3A Moss uprated water pump

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Jedi Knight
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What is the correct size and type of the keyway and what is the shaft diameter in the stock pump?
I ordered a spare water pump for my tr3 ,Moss uprated pump w/o pulley that was back ordered,but shipped today.
I want to verify it will fit with no modifications,the way my Moss aluminum pulley that came with the fan eliminator kit fit the original pump shaft,just right.
Pump and pulley are assembled so I cant measure.
Thanks
Tom
 
The width of the stock key and keyway are 1/8 inch. I do not know the length of the key. Some aftermarket Moss pumps have had a 3mm key. Be careful not to put a 1/8 pulley on a 3mm key. After you run it a short while, you will not be able to get the pulley off.

Bob
 
Thanks Bob,Some previous posts mentioned a #5,which would be a woodruff 1/8 x5/8 x.24,according to McmasterCarr.
I think shaft diameter is .625 but havent measured or seen this posted.
Since this may sit on the shelf for awhile I want to verify upon delivery.
Tom
 
Here's my experience:

Engine Externals

tr4a.nonlintec.com

Scroll down to the section about the water pump.

I'll never get another one of those "uprated" Lucas pumps. The original ones work fine, as long as the cooling system is otherwise in good shape. And if it's not, the solution is to fix the problem, not just add a bigger pump.
 
Dear Steve,
Thank you for posting your incredible restoration archive: The timing was perfect, as I'm just about to tear into re-commissioning my '65 4A!
 
Sarastro said:
Here's my experience:

Engine Externals

tr4a.nonlintec.com

Scroll down to the section about the water pump.

I'll never get another one of those "uprated" Lucas pumps. The original ones work fine, as long as the cooling system is otherwise in good shape. And if it's not, the solution is to fix the problem, not just add a bigger pump.
Click to expand...

Steve I reread you post and it seems the problem was the pulley keyway and supplied key 3mm not 1/8.
Considering the required grinding for pulley clearance it seems your pump was ok but the key and pulley were off spec.
if the pump comes with an 1/8keyway I'll be happy.
I have the aluminum thin belt and a good original pulley.
For 60 bucks ,and the little available others, I think It has the possibility of still being a good option,if it doesnt leak.
Thanks for posting your experience and the link.
Tom
 
Moss uprated 5 vane pump arrived.
Shaft measures .62495.1/2 under what I think should be .625. A 1/2 over would be better.
Keyway is .125 but supplied key is .1235,1 1/2 under.No big deal I have lots of keys.
Original pulley that I pulled off the original pump, now in service with an aluminum pulley,drops on the shaft and the pulley with key installed can rock on the shaft.I can lift the pulley off without the pump moving.
I will be returning.
Also I noted on their site that a "fix" is to dimple the key or use loctite on the assembly.This reminds me of an old refinery motor pool mechanic that told me he usually has three possible results.Fix it up,Juke it up or F it up.Their fix seems to me a "juke it up"
Tom
 
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