Water Pump ID

[GlennW]

Got the water pump shaft wiggle blues so I pulled it and I'll be ordering a 1560395 complete unit. The old one doesn't have the 3 reinforcing flanges and the casting number is four digit- #32??. Anyone know what this is, perhaps a generic NAPA, Champion or Airtex one? After I get everything back together and buttoned down I don't want to toss the old one if it's a core somebody might want to rebuild for a non-Avanti application.

Edited September 29, 2014 by GlennW

[JLBKY]

Got the water pump shaft wiggle blues so I pulled it and I'll be ordering a 1560395 complete unit. The old one doesn't have the 3 reinforcing flanges and the casting number is four digit- #32??. Anyone know what this is, perhaps a generic NAPA, Champion or Airtex one? After I get everything back together and buttoned down I don't want to toss the old one if it's a core somebody might want to rebuild for a non-Avanti application.

Glenn.........before you install the pump, check the specs on the location of the machined edge of the impeller to the mounting face of the pump. It should measure .934 to .938. I recently replaced my water pump and found that both the old pump and the new pump both failed to meet this spec.Using a gear puller, I pulled the impeller to get it within the spec. When I put it in the water pump manifold, with out the gasket, and spun the pump, I could detect a very slight interferance/contact of the impeller and the housing. Installing the gasket ( approx .004 ) and spiniing it again..........no interferance.It now cools much better.

I made this change and a couple of others cooling changes this past winter that resulted in my '63 R1 A/C car struggling to get to 180 in city traffic with the A/C on in 90+ weather. A 42 year battle that I finally won.

John

[GlennW]

Glenn.........before you install the pump, check the specs on the location of the machined edge of the impeller to the mounting face of the pump. It should measure .934 to .938. I recently replaced my water pump and found that both the old pump and the new pump both failed to meet this spec.Using a gear puller, I pulled the impeller to get it within the spec. When I put it in the water pump manifold, with out the gasket, and spun the pump, I could detect a very slight interferance/contact of the impeller and the housing. Installing the gasket ( approx .004 ) and spiniing it again..........no interferance.It now cools much better.

I made this change and a couple of others cooling changes this past winter that resulted in my '63 R1 A/C car struggling to get to 180 in city traffic with the A/C on in 90+ weather. A 42 year battle that I finally won.

John

Great minds think alike Yeah, the smaller you can get the impeller/housing gap on this type of pump, the more efficient it'll be. Of course it's like a contest to get closest to an alligator without getting bit-loser gets bitten. When I'd pulled the water pump there was freshly honed edges on 3 of the 6 vanes so I knew it had been at minimum tolerance and the shaft tilt from the worn bearings let them touch off. I measured the vane depth of my pump and the mean was .946" no more than +/- .003" from vane to vane. The Shop Manual spec. is listed as .934"~.938" so it's understandable it started to drag. Too much of a hassle to get in under the hood with a drop indicator fixture but I'd have to assume my manifold has .950" clearance. I don't have cooling issues or even have the AC belt installed since the AC didn't work in 1981 when I bought the car and live in WI where that's not a hardship enough to want to comepletely re-do it correctly. Faced with an "all or nothing" situation I found I could tolerate nothing

Edited September 30, 2014 by GlennW

[GlennW]

FWIW, got the new pump from SI today and the vane depth is .940" and the pulley mounting face dimension is within .015" of the old one. I'm not going to touch a thing. I'll put the pump on by itself and give it a spin, .940" is less than the one that came out so it all should be golden.