On Mon, 31 Oct 2011 17:18:56 -0700 (PDT), andyeverett
wrote:

I have a Dewalt 3800 power washer with a Cat 67DX39611 pump. This unit
gets infrequent use for my business. Normally when I connect the water
hose and turn the water on and pull the trigger water comes out the
nozzle. Today it did not. When started no water came out. Some gentle
hammering on the pump, nothing. After some tinkering I thought it
might be the inlet check valves sticking. With the water hose
connected I clamped the garden hose tight and then struck the garden
hose with a hammer between the clamp and the pressure washer. The
pressure pulse must have freed the check valve (valves?), and I got
the washer working. Tonight after reading the manual I learned that
the there is a special fluid DeWalt DP80 (or RV antifreeze) I should
be working into the pump when it sits for more then a month.

What if anything do you do when your pressure washer sits for a while?

Thanks for any help!

If it stays outdoors in an unheated building, you MUST drain it or
freezing water can ruin it. I always pump mine dry, then prop it up
so any remaining water can drain out. I also have a small portable
one, that one just comes indoors in cold weather.

Pouring a little mineral or vegetable oil in the inlet cant hurt
either.

RV antifreeze is cheap, but how do you get it in the whole unit?