[Earle]

I have had a Snyders leakless pump on the roadster for about 4 years and 3000 miles. Zero leaks.

Ora Landis recommended and installed it back then and I don't recall all the particulars about it. I believe it has the lip seal at the rear & permanently-lubricated needle bearings at the front. I know it has the two fake grease fittings and stainless steel shaft. Absolutely maintenance-free.

Still has no detectable axial or radial looseness.

I have always run 50/50 antifreeze/water. It definitely does improve lubrication of the rear pump seal compared to water alone (aside from all the other benefits that antifreeze provides for the cooling system).

If the bearing quality, tolerances and installation are done right, the needle bearings are superior to ball bearings because they have a larger contact area with the shaft to distribute the radial loads - compared to the small point-contact of ball bearings. Needle bearings are intended for applications involving higher radial loading such as produced by the fan belt tension. But they are way more intollerant of any shaft misalignment.

You will always extend the life of a water pump - especially its front bearing - by running the fan belt at the very lowest tension necessary to keep the pump and generator spinning without slippage under typical driving conditions.

Also, any imballance in the fan will act to increase abuse of the front bearing and lead to early failure. But a needle bearing will take the "abuse" longer.

Since I am a "belt + suspenders" guy, I like the earlier tip on adding a drop of oil to the pump shaft at two places on the leakless pumps. Makes sense. Gonna start doing it.

Earle