I can not keep this thing running. When I start the thing up it runs maybe 20 sec. and stalls.If I hold the trigger in it will run fine w/ little out -put pressure.Also when the engine stalls it will not allow me to pull start until I bleed the water pressure off.the P/W is a Generac Res. P/W 2.0 2100 psi 6hp B.S. model#01439-0 Type 4200 CP. Thanks for any & all advice.

 

Sounds like the unloader valve is stuck and not relieving the pump when you release the trigger. There are so many configurations, but usually it is a brass valve or plug screwed into the pump near the area where the pressure hose connects.

 

Thanks Cheese,I was thinking maybe the unloader valve will replace it today or tomorrow.I have a busy day today w/ school ending and field today. I will keep you advised to the out come. Thanks again.

 

Are they the same thing ? I replaced the valve that allows water to discharge.the motor still stalls.Also,I bought the p/w from a neighbor who removed the pump to change the oil and put 10w/40 oil back in the pump.Could the oil be the problem or maybe the pump is torqued to tight.

 

I believe the pressure relief valve is basically a popoff valve to prevent severe damage from excess pressure. It isn't the same as the unloader. I doubt the oil or torque has any bearing on this problem.

 

Okay,there are three brass plugs on the frt.side of the pump.What do I need to do to service the unloader valve? Do I just remove the plug and valve or do I have to remove the complete pump.

 

Those brass plugs cover diffrent valves (check valves). The unloader should be in the circuit between the pump and the outlet for the wand hose.

 

Servicing it would consist of doing what to the unloader valve.Should I spray say WD-40 into the valve or what?

 

There are many parts to an unloader. Piston, o-ring seals, spacers, springs, etc. Disassembly, cleaning and lubricating with petrolium jelly would be best, if it is serviceable that is.

 

Okay,the large black plastic plug which is in the circuit by the water inlet contains the unloader valve and not one of the brass plugs.If this so how do I remove the plug.I tried w/ a socket but was unsuccessful I rounded the plastic nut off.Also,I removed the brass plug and cleaned the check valves.Do I have to tighten the brass plugs a certain torque?

 

Ok, NOW I know EXACTLY which type unloader you have. The hardest one to get off, lol. The only way I've ever been successful at working on this type is to use a quality pair of curved jaw channel locks. Even then, it may not come off. If you try with a poor quality pair of chennel lock type pliers, it will probably chew the rest of the plastic off to the point that nothing will remove it. One other thing...you could drill a hole all the way through the rounded nut and push a hardened rod through one side and out the other to make a sort of "T" handle to help remove the nut. I did this to one I chewed up trying to remove so that I could tighten it back up and it worked well. If you get it off, a spring with a spacer behind it will come out, then you might have to use a thin pair of needle nose pliers or retaining ring pliers to get enough grip on the unloader piston to pull it out. The piston may need a new Oring, and cleaning, and the cylinder may need cleaning. This is not a typical unloader vlalve setup/location like you'd find on most pumps.

On the brass plugs, just snug them good-n-tight.

 

I drilled a hole through the plug, bent a screw driver and busted the plug head all to peice's.Do you have any suggestion's on removing the remainder of the plug.I know there has to be threads some where inside of the cylinder.

 

Oh man...been there before. This is where I usually quit and tell the customer they need a new pump, because it's probably going to bust anyway. Not to mention it's not worth the labor rate to remove it.

I suppose you could use a dremel tool to try to cut the majority of it out, and what's left in the threads should then break out easily enough.

 

Thanks for the advice throughout this task.My luck,I bought the P/W used for 100.Do you think it would be worth another 70-80 to fix it?

 

I guess if it runs fine, and 70-80 bucks will fix it, then it's probably worth doing even if it doesn't last all that long (year or two). I mean, it'll cost you that much or more to rent one a couple of times, so I guess it's worth the expense.