P6 3500S NADA water pump adaptation

gbvona

Member
My old water pump (1971 3500S NADA) leaks. Yep, it's the one with the viscous coupling and big fan (AC, y'know, which is long dead). I have a replacement pump with the big aluminium casting on the nose. The two pumps look essentially the same, though it appears that the new one has a slightly longer input shaft.

So how does one adapt the new pump to the old pulley arrangement?

(1) Gotta remove the big casting off the nose of the new one. My instinct is to heat it pretty well, then proceed with a press. Or?

(2) Gotta shorten the input shaft of the new one. Seems a hacksaw and file would work. Or?

(3) Here's the hard one. Gotta get the old nose (hub assembly for viscous unit) off the old pump, without damage. The shaft appears to be pressed into a blind hole in the hub assembly. Only idea I have is to saw the input shaft/hub assembly off the old pump, drill the shaft remnant down the center, thread the hole and use a bolt to pull the remnant out. Or??

Suggestions welcomed.

gbvona
 
There are repair instructions for the original pump in the very first workshop manuals. It involves heating the thing up in oil and pulling the impellor off, replacing the seal (standard type seal) then pressing it back on. You can change the bearings at the same time (also stock bearings)
 
My old water pump (1971 3500S NADA) leaks. Yep, it's the one with the viscous coupling and big fan (AC, y'know, which is long dead). I have a replacement pump with the big aluminium casting on the nose. The two pumps look essentially the same, though it appears that the new one has a slightly longer input shaft.
gbvona

Hello gbvona,
did you resolve your Problem? the water pump on my nada with air con also started to leak this year (after 48 years working fine)

Does anyone know, if it is possible to use the Standard Rover P6 V8 water pump (GWP310) on the Federal/NADA, because I changed the viscous coupling/fan blade to a electric fan many years ago.
So, maybe I do not need the NADA water pump, just the Standard Water pump. Would be interesting to know.

thank you,
Kind regards
Richard
 
Does anyone know, if it is possible to use the Standard Rover P6 V8 water pump (GWP310) on the Federal/NADA, because I changed the viscous coupling/fan blade to a electric fan many years ago.
So, maybe I do not need the NADA water pump, just the Standard Water pump.

I think you should be able to, you would just need the 3 bolt waterpump pulley to match the pump. AFAIK the crank pulley and alternator pulley are in the same alignment for both pumps.
 
Brief update, I did get the "nose" (pulley flange) off of the old NADA water pump. I tried threading a zerk grease fitting onto the blind end and forcing it off with a grease gun, but there was simply not enough pressure to do so. In the end, I removed everything on the pump shaft (which involves considerable destruction, e.g., the bearing, but it was rotten anyhow) and welding a bolt onto the impeller end of the shaft. Put a piece of pipe over the shaft as a pusher, with a flat plate (hole in the middle) over that, nut on the bolt and used it to push the nose off. Worked a treat. The new pump shaft is too long, shortened it with a cutoff wheel (shaft material is VERY hard) and pressed the old nose onto the shaft. Voila! And the pulley fits nicely.

Should be obvious, but this is only necessary if you keep the old fan. If you replace it with electrics, you can use the new style pump as is, but will need a new style pulley.

gbvona
 
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