Tips and suggestions for overhauling the water pump needed

[aldo]

The water pump is leaking from the front somewhere behind the pulley. I removed the pump and the bearing feels worn and loose. I'm reading the dexta workshop manual, and it calls for overhaul kit tools T.7000, T.7000-17, split adaptors, etc. etc.
Now I know in my experience with similar 'special' tools with cars, such tools do make the job easier, but when you know what your doing, often they can be replaced with something like a big screw driver and hammer!
Can anyone give me any tips, suggestions, advice, on the best/easiest/safest way to dismantle the water pump? I don't want to crack anything pressing or pulling the wrong way. At work I have access to mills, lathes, a press etc, so I can make what ever tool I need. Thanks.

[terry274]

Aldo, I have not yet had to work on my water pump, so I won't be able to offer any specific advice. But I did look at the manual, and I believe if you are careful to distribute the force evenly and as near the shaft as you can get you should be safe with a gear puller or hydraulic press. I would soak the shaft in penetrating oil for a day or two before I put much pressure on anything. A little heat might help also.
Good luck, let us know how things go.
Terry

[aldo]

Thanks Terry.
I was thinking of pressing the shaft straight out , but don't know if the casing can take it. And I don't know what sort of bearing it is, looks like its just a bush. So might do some damage finding out.
I can get a rebuild kit (shaft and bearing, with seal and impeller) for only $55, but if I damage the casing, will need to fork out $170 for new complete unit.
The pulley is quite long and wide, and you can't get in close to the shaft to support it when using a press. I was thinking of removing the pulley by screwing a plate to the fan bolt holes, then with a nut welded to the centre of the plate, screw a bolt in, to push the shaft out. That should work just as well as a gear puller, if its not too stuck.
Now I just realised, all I need to do is remove the pulley and push the shaft out of the housing, don't need to disassemble the shaft because I'm throwing the whole lot out, replacing with new shaft and impeller. Thanks.

[Kiwi Kev]

Aldo
See how good it is to talk things through. You solved your own problem by yourself.
When I did my Major water pump, the hardest part to remove was the boss for the pulley. Gear puller and a bit of heat. The rest of it was done by using the vice as a press.
I do remember that I had to get the clearance between the impellor and the housing right. I seem to remember 30 thou clearance, for the Major.
Good Luck
Kiwi Kev

[aldo]

Thanks Kev.
Terry, it all went well. The fan/pulley unit came off easily using the tool described earlier - I drilled holes in a bit of 10 mm plate to match the 4 fan bolt holes, and bolted the plate to the pulley. The original fan bolts aren't long enough, I found some longer ones. I also drilled a hole dead centre of the plate, and welded a 12 mm nut there. So screwing in a 12 mm bolt pushed the shaft out, and it didn't need much force at all ( I was worried, because the pulley looked rusted on, but once off, the shaft looked shiney and new).

To push the bearing and shaft out of the pump housing I used a hydraulic press and the equivalent of one of the 'special' tool attachments. I made my 'special tool' out of a bit of 30 mm diameter shaft. The pump bearing is 30 millimetre diameter, and the pump shaft is 16 mm diameter. So i turned the tool down to 29 mm, and drilled a 17 mm hole down the middle of it. So the tool slips over the pump shaft, and presses down on the outside of the bearing. Came out quite easily, and the new one pressed in quite easily, using a hydraulic press.

Sorry about the metric system, I didn't invented it, I believe you use inches. I don't know how familiar you are with metric, so 1 mm (millimetre)= 0.0393700787 inches.

[terry274]

Glad to here things have gone well for you. Thanks for detailing the process you went through to get the shaft out, it will help other people with their water pump.
We use both inches and the metric system where I work. The metric system is much easier and is more common sense. But I learned the inch, foot, yard system as a child and old habits are hard to break!
Terry

[aldo]

My first 2 years of school was with inches, feet, yards, but then Australia decided to change everything to metric. So I always work in metric, but strangely in general discussion, I still will say that something is a few inches long, or a couple of foot long. etc. Also if you told me you were 180 cm tall , I don't get a mental picture of how tall you are, but 5' 10", I get the picture exactly. Same with the size of waves in the surf, still often described in feet.