> Where did the 2" hose requirement come from?  Wasn't Tracy
> running with 5/8" hose to his radiators?  Can we get a survey
> of working installations to see what size hose is sufficient?
>
> This is a significant issue for me.  I'm considering a
> remotely located radiator.  Running 2" hose for 7ft or so is
> out of the question.

It's not a requirement at all. It just happens to be the maximum hose size specified for this pump, and I figured I'd pick it to give Jim the fairest possible comparison since he's thinking of making one. If you want to search for more suitable options for you, the place to go is www.mcmaster.com and then click "Check Valves" under Process Control and Instrumentation. It's the fifth item or so on the line.

I didn't like the options on the first page for a variety of reasons (size, temperature handling, etc) so I browsed through until I hit page 370 (see the link at the top of the page). The item I picked was "Bronze Class 125 Horizontal-Swing Check Valves", and I selected the 2" valve to give the highest price possible for comparison. If you have, say, a 1.5" dia cooling hose, you want 4708K57, which is only $40.19. All prices are USD.

Note that these are "horizontal swing" valves, which are very similar to the descriptions Jim and Ernest offered.

Whoever buys one first, would you please let me know what they weigh?

Regards,
Chad