Model A

Ford Garage

Reproduction Two-Piece Water Pump Shaft

Here are a series of pics outlining the construction of the reproduction two-piece water pump shaft assembly having two roller bearings and a sleeve.

The basic idea is that this assembly can be press-fit into an original water pump housing casting with no machine work required to the housing. Sounds good, so far.

The pic above shows the shaft with what appears to be two roller bearings pressed onto the shaft. Then there is a thin wall sleeve which fills the gap between the outside of the bearings and the inside of the casting bore.

The roller bearings are sealed and there is no means for additional lubrication to be added.

I wonder how they hold those bearings in position on the shaft? Oh, Wow, it's a two-piece shaft! I wonder what holds the two pieces of the shaft together?

The front stub shaft that mounts the fan is about three inches long and has the back end turned down to 12 mm diameter. Two metric bearings are pressed on the tail of the stub shaft. Then the end of the tail is pressed into a bore in the end of the larger and longer 5/8 inch diameter shaft.

Sometimes people really out-smart themselves!

Pretty tricky how they made this thing look like an original 5/8 inch diameter shaft when actually it is a less than 1/2 inch diameter stub shaft at the front where it should matter most, and it is held together by a silly 'press-fit' (slip fit?).

The other thing that defies logic is the fact that for some reason the reproduction shaft manufacturer removed one seal off of each bearing and faced the two open bearing sides together. Why?

These two bearings are 2RS 6001 bearings which means they were originally lubed-for-life and double sealed. Now there is no provision to add additional grease to the bearings, so why un-seal them and expose them to contamination? Brilliant!

As far as I am concerned, it is no longer a lubed-for-life sealed bearing when it has been opened. It does not take much contaminant to enter and ruin a precision ball bearing.

Thanks, but 'No Thanks!'

I prefer to have the radiator fan securely attached to my engine, and not on some short, small-diameter, press-fit stub shaft which is being cycled by the constant belt loading as it rotates.

I can just visualize the press-fit working loose and walking, and the fan plowing through the radiator.
Then again, I've never heard of it happening yet!

And if that's not bad enough:

Hard to see in the pic, but the taper on this two-piece shaft assembly is actually the combination of two tapers (neither one correct) and has a distinct transition between the two tapers. JUNK! I put this on a lathe and reworked the taper until it was "usable", though I certainly am not going to be using it.

I wonder why it is so hard for suppliers to make such a simple part to the Ford print?

I won't be using this part, but Hey, Let me know how this shaft works out for you!

Click Here to follow the adventures of the poor quality available one-piece water pump shafts!

April 2002