German13, I built that setup. Had a 3/4" ball valve to a 3/4" inch ID hose coming out of a new 125 gallon poly tank. Then to a purge valve (for easy water flushing), a short nipple into the 4-Roller Hypro Pump. From there, I went with a short nipple to the 150 PSI Pressure Bypass Valve. The bottom 3/4" ID hose went off the Pressure Bypass Valve to the hose reel spooled with 150' of 1/2" ID hose, and the top 3/4" ID hose went back to the top of the tank for recirculation and pressure blow off when I was not spraying.
We tested with water at first, all went well. Then when we put our coal tar sealer and added our 30% water. We mixed it with a paint stirrer on a drill for about 15 minutes. We recirculated for 30 minutes successfully. Then we turned the Pressure Bypass Valve down and tried spraying the mixed sealer...it hardly sprayed. So we recirculated for a another 20 minutes and tried spraying again. It was still too much for the pump as it was hardly spraying. We even took the gun off. Still not enough. We were catching some thick sealer.
During that testing period...the pump failed.
Here is what I believe happened. I think we had some thicker sealer down by the outlet inside the tank on the bottom even after all that mixing and recirculating. The pump just could not push that little bit of thicker sealer sealer through that 1/2" line and failed.
Now I got a $209 cut piece of 1/2" ID hose that I don't think I can return. Maybe if we tried 100' of 3/4" ID hose on the hose reel, it could have worked.
So here are the changes I am making. I am running a 2" ball valve off the tank into a Harbor Freight 2" trash pump. From there I will run a 2" T with (one 3/4" outlet to hose reel) to a 2" ball valve to the top of the tank for a full 2" recirculation. That will mix it up real good.
I am not to sure if I should leave that 1/2" hose on the reel though. I will try it real fast with the new pump at just above idle. Who knows....might work after that good old 2" recirculation mix method.
I really wish that Hypro setup would have worked.....
You must be laying some pretty thin stuff down.