G.W. Thank you man for all the knowledge and experience (combined) that you post for immediate and future reference.
I'm not try to counter or fight your last post due to the fact that I do not have any experience bilge pumps whatsoever.
The thing that encouraged me in the article was about restricting the outflow not wearing on the motor of the pump.
Specifically.....
"With centrifugal impellers, restricting the flow rate with a valve reduces the power required proportionally. When pumping fairly cool water, these type pumps can be choked back to very small flow rates without any harm to the pump or motor."
Like I said, I truly have no idea of the truthfulness of this statement. What is your experience with outflow restriction and motor wear?
basically resistance is resistance. Bilges wear over time when they are run a lot. They are not designed to run a lot.
I have two rule bilges I use on my blue bowl. the one I've used the most requires the valce to be open more for higher flow.
So, yes I restrict my out put. But its for a blue bowl so it does need the adjustment. I switched to the new unused pump recently because I was getting less response and I was trying to see if it was my battery ot charger. Nope old used up bilge.
they lose their umph over time it is a combination of the way those dc motors work and fine sediment...even just cloudy water has an effect.
A bilge is wearing out from the first use. resistance adds to that. Head is resistance.
Per that article it is related to industrial constant pressure pumps. Click on the products and the relevance to bilges used by prospectors in garages quickly fades.
I have yet to try and run a larger piece of gear a recirc or small cleanup/concentrator and actually wished I could get less flow.
To be honest life span due to wear is less of an issue than will the damn pump be enough if you have say three feet of head from your reservoir to out put.
Height to output, smooth wall hose vs, ribbed. 90's and 45 elbows...connection fittings. All add to head resistance and wear on a bilge.
This shows factory stated spec vs. actual test. Either way look at what just height does to flow
https://www.google.com/imgres?imgur...trXAhWHxFQKHeKDA2QQMwhAKAMwAw&iact=mrc&uact=8
basic flow performance
http://www.strongmanpumps.com.au/wp-content/uploads/2017/02/Rule-Pump-Performance-Chart.jpg
My internet sucks took me an hour to get this
Digging to do Ill be back tonight