VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 Water pump shaft end play

While checking over my 36 Standard Coupe with the engine idling and reving it up slightly I noticed the water pump shaft moving in and out on the revs.I shut if off and loosened the fan belt and can easily move the shaft in and out approximately.080"+.There is no up or down play or leaks,I tightened the packing nut slightly but still no change and have searched all books I have and find no spec for acceptable end play,all info says tight but not binding.I looked over a spare pump assembly I have and it doesn't have nearly as much in/out play.I noticed the shaft appears to be pressed into the impeller.Has anyone else run into this problem and could this be a packing/spacer failure in progress.Any help or past experiences with this problem will be greatly appreciated. :confused:

Thanks
Philip J'ville Fl.

The end play on the 1929-36 water pumps is determined by how far the pulley is pressed onto the shaft.If your bushings are in good condition-front has a "hat" type bushing for end play thrust,pressing pulley on a little farther should cure your problem.Note that there is an oiler hidden behind the pulley as well as the grease cup.Oil placed in the front oiler soaks thru the brass bushing for lubrication.

Found a little more info. that may help you.I opened a water pump repair kit that I have.There is a Bakelite thrust washer thay rides aginst the impeler.Then the small rear bushing-the seals and the large front bushing.The front bushing has a thrust flange on it.The Bakelite washer is about 1/16" thick.Yours may have worn out or the flange on the front bushing may have worn away.When the parts are assembeled the pulley is pressed on until the is no end play but the shaft turns freely.I think it would be best to remove the pulley and inspect the internal water pump parts.

If the composit washer is not in place the impeller will touch the housing. I suspect the pulley has moved (due to misalignment of crank, water pump and/or generator pulley) or was not installed properly. In any case it will be necessary to remove the pump to correct the problem. If the pulley is found to be a bit loose a drop of loctite will solve that problem. But be careful as any loctite getting between shaft and bushing will lock the shaft to the bushing. If you oil the bushing then the potential for problems can be minimized.

Any wear on the impeller thrust washer or on the body casting where the thrust washer turns will cause end play between the front bushing and the pulley. Both the water pump body casting, the thrust washer, and the face of the front bushing should be inspected.

I checked a new water pump.The space between the impeller and the body is about 3/32" with the washer inplace.Of course is rubs when not in place.If the pump is removed that demension can be checked with out farther disassembly.To check the front of the front bushing for wear the pulley would need to be pulled forward a little.The bushing thrust flange should be about 1/8" thick........From personal experiance I can tell you what happens when the pulley moves too far ahead on the shaft.Ths fan marks are still on the back of the core on my '34.

Chev Nut is very correct. I have seen several radiator cores that have damage from the fan due to excessive end play from the impeller shaft. It ain't pretty! :eek: :eek: :eek:

Thanks everybody for all the great tips,I really appreciate the help.I've seen a core eaten by a fan due to a bad pump shaft before and yep it sure ain't pretty .I'm gonna pull the pump this week and check it out.I replaced the radiator core about seven months ago and that took care of my overheating problems.It looks like with the fan removed theres enough room to get the pump out,also I'm going to cut a piece of cardboard to use as a shield in front of the core so I don't bend any fins.When I bought the 36 alot of extra parts came with it which included a water pump with pulley,this pump appears to have about 3/32nds end play as ya'll mentioned earlier.The impeller does show signs of pitting but the pump appears to be rebuilt so I may give it a try before purchasing a replacement.Thanks again and I'll keep everyone posted on the repair :)