Water Pump Bully

[rpgdeity]

Whoa, I always thought it was a tapered shaft holding the pulley on. Wow, a press fit on that shaft, no wonder it takes so much force to pull it off.

[brute4c]

Maybe thats the secret....

[george walker]

even though its press fit there can only be so much difference between the shaft diameter an the pulley bore or pressing on the pulley would split it, lots of other automotive pulleys are press fit and dont take all that much effort to get off, how can these pulleys resist so much force, is there a small weld under the pulley maybe, i see a clip that retains the brg in the housing is it possible to get it released w the pulley on then get the pulley off the shaft after its out of the housing?

[Fastfrankie]

Just my two cents...there is a guy (machinist/mechanic/rebuilder - one man band) near me who rebuild these. I never cared as to how he gets the pulley off the water pump etc since he is cheap and if one of my pumps ever need rebuilding, I'll take it to him.

He did one for a guy on here (Robert Chambers) years ago and thats how I found out that he rebuilds them. I knew this guy for years but never knew he had the capability to do the pump.

Apparently, he told me he made a special jig so that he can get it off and on. This guy is a mechanical genius who can rebuild anything. Best part is, he is cheap! If I ever need to go see him, I will find out how he does it...and I am sure he will show me since he probably has only done a few in the past decade.

[Barrman]

Something that makes it easier is to bore out the threaded hole in the end of the pulley. I think stock is 1/4 or maybe 5/16 diameter. Drill it out to fit 7/16 fine threads and it will pop right off with a normal sized wrench doing the twisting on the bolt.

My machine shop guy and I have gotten that far. We have several pumps all the way apart. I need to call him up and convince him to look through catalogs and catalogs worth of bearings/bushings/seals looking for the exact size parts we need to do a correct rebuild. His enthusiasm waned after the first few pages of seals with about 20 listed per page.

Once we get the seals/bushings/bearings all figured out, we will tackle the pulley installation.

[airborne]

Soooooooo, drill to 7/16, and use a bolt to pull the pulley off? It can't be that simple, can it?

[Barrman]

That worked for me. Putting it back on methods that work will be revealed when we get that far.

[airborne]

Ha,ha,ha! Alrighty then!!!!!

[adk4x4]

I just had this done at a local shop and the guy said he rigged it up into his press and heated the pulley and off it came. A learning curve was involved, especially the rigging part, but it did come free without damage. I had already bored out the end thread for a larger rod to push with. However, I like the idea of just using a fine thread bolt to extract.

This is how most snowmobile clutches are removed, a large pin threaded half way that mates to female threads on the clutch bore and just apply air impact and done. Hardened pin and tapered shaft make for easy work though.

As for going on, the old heat it up and drop it on was all it took. Similar to replacing a starter gear on a flywheel.

He charged me $30 but would do the next one for half that now that he knows how the rig it. Unfortunately I wasn't there to see the rig, just heard about it. I have a spare junk one that I might try the larger bolt idea just for kicks. VPW only offered me like $10 for it as a core.

[Team Nefarious]

I've made significant progress since last posting but am still against a stop point. I have fully dismantled the water pump. The suggestion to drill and re-tap the hole in the end of the pulley to a 7/16-20 was what did it. But by the time the bolt moved the shaft the force was sufficient to change the shape of the bolt (or threads in the pulley) that I couldn't just spin the bolt out and had to wrench it all the way out. What they do shrink fit the bugger on? My snag now is replacing the bearing.

As you can see I still play too rough and broke the outer race, I was hoping to separate the shaft and bearing. I did succeed, just not the way I hoped... So any way I went to a local bearing distributor to guide me to the selection of a replacement or suitable retro fit. Here's what the guy said (1 - NDH the company that made this bearing was known for producing unique and oddball applications (like this thing). Also NDH no longer exists and hasn't been around for years. (2- After looking around and referencing several catalogs he could locate no sealed bearing that would carry a .625 shaft and have an O.D. small enough to fit the 1.187 bore of the pump housing. Any one got a thought or suggestion to throw on this one? I didn't ask about unsealed bearings, but a couple miles after driving off the thought occurred to me I should have asked if there would be an unsealed bearing that would otherwise fit the application and then try to generate a separate seal later. I would hope for a simpler solution but where's the fun in that?