Pressure Washer - Off Topic

[Mark Page]

My Generac pressure wash washer won't develop pressure. All the screens have been replaced. I replaced the trigger gun, the nozzle and the wand. The engine runs strong and I have an ample supply of water. Generac admits that the pump is a pc. of garbage and will gladly sell me an upgraded pump for $250. It has had little use over the 10 years I've owned it. Does the pump have a part that can be replaced?
It generates about the same amount of pressure as the nozzle on a garden hose.
As mechanically inclined as you guys are I figure someone might have the answer.

 

[Scooby074]

If you have enough water getting into the pump (inlet screen and hose is OK) you should be building pressure. Looks like youve done all you can (changed nozzle,trigger etc.)

That's sort of the problem with these cheap pressure washers.. they arent cost effective to fix. There are little pistons and check valves inside the pump and that is how it builds pressure. You could try pulling it apart and check the check valves. Sometimes dirt and rust etc. can jam them open. What about your relief valve, is it working, adjusted right? Id check a few of these things, but I wouldnt put any more money into it personally.

Your best bet is to buy a GOOD quality replacement pump, one with ceramic plungers. What engine is on your generac? Is the pump belt drive? You need to know these things in order to match up with any pump or adapter. CAT and Comet pumps are probably the best quality for a reasonable price. I have a Comet on my washer. I would not put a Generac unit back on there!
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[J_J]

Plug in a 3000 psi gage into the PW and read the pressure. If the PW is a 3000 psi unit, the gage will show 3000 psi when the trigger is off. Normal operation will show something less depending on the nozzle used.

If you are reading 30 to 60 psi, that is normal water supply for a house.

The pistons and seals are what pumps the water, and if good, and the water is passing through a small nozzle, that is what develops the pressure.

There is an unloader in the flow path that will unload the pressure when the trigger is off. That only works with pressure, and is spring loaded.

Is your pump actually turning.

If you take the PW head off, you can see the pistons moving.

 

[Powerhorse]

If it's dircet drive and the key comes out from the shaft it will not spin the pump. Had this happen to a northstar washer. Work was going to trash the washer cause it stopped working so I took it. I about gave up on it and decided to remove the pump to save the engine and found the key out. Replaced the key and it's still going for the last 8 years. Tecumseh 10 hp 3000 psi general pump.

 

[cnice37]

Is it an axial or triplex pump? If the pump is made by some name brand (AR, General, Cat, etc.) then rebuild kits can be purchased. In my case it was a HD cheap-o Axial made in China and I couldn't fix with what I had on hand and couldn't rebuild aside from the O-rings I had on hand.

Good luck. The Generac my FIL just bought came with an AR triplex pump, so it should be decent but that was a higher end unit.