My original pump had several leaks, and I replaced the pressure regulator assembly a few years ago. It was the original D____S OEM brand. Had many problems with this pump leaking because the threads on most of the components were very fine and could actually be stripped easily if tightened too much. The problem was, it would leak unless very tight. Go figure. This new pump looks to be built much better, and was less costly than just the parts for the old one. I had a tough time removing the old pump from the shaft because it was quite rusted. I had to take apart the front and back covers of the pump, and ended up using an air chisel with a blunt end to actually push the pump further onto the shaft slightly. Once I could tell it moved, I was able to pull the pump off. I wire brushed the engine shaft until it was like new, then greased it slightly. The new pump slid right on, I re-used the old bolts to fasten it, then installed the fill cap. Cleaned up the area, hooked up the water hoses, and I had pressure like never before. WOW! I had to hold onto the sprayer handle very firmly as the pressure of the water really pushed me back. The spray is not only powerful, but very even with each of the nozzles. I ordered the 4200/4.0 unit btw. This pump is awesome, much quieter, and although I have just started using it, I can tell it's built to last. Extremely happy I chose this pump, both for the cost and performance. It took me about 2hrs to remove the old pump, about 10 min to install the new one.
Gérard Dalpé 
Dustin 
