Outdoor Power Equipment and Small Engines - Pressure washers

I am in the market for a pressure washer and I'm not sure exactly how much power I will need for the various applications I plan on using it for. Does anyone know how much water pressure to use for different applications? For instance, I would be using this for tough cleaning jobs (ie, concrete stains, aluminum siding mildew) but also for washing the car and other light duties. I have read that you can destroy a wood deck and aluminum siding by using too much pressure. But what is the max pressure you would want to use on wood and/or aluminum siding? Would it be safe to assume that too much pressure could also take paint/finish off of a car? I was looking for one with about 3000 psi w/3.5 gph throughput but I noticed that not all of them have a pressure regulator to reduce the pressure output from its highest rating. So, any ideas on suggested pressure settings for these various tasks? Thanks.

Hello JCox!

I know a bit about pressure washers, but not their suitability for different applications. Check back often, someone will probably have some advice for you.

I just bought a display model closeout or discontinued preasure washer today 3400psi 4GPM 11hp B&S craftsman from sears at less then half price. I believe it has an adjustable preasure regulator. I have only used a preasure washer once before and learned quickly that the water preasure can remove concrete if you keep it in one place to long. I to will have to monitor this forum to learn more. I'm using it for home owner use and chose a more powerful one to make a little money on the side should someone want me to preasure wash something requiring more preasure.

The only thing I may not like about this B&S engine is I'm not 100% sure but it may have fixed jets in the carburetor which means there no adjustments for rich or lean. This preasure washer is listed as 135 lbs. dave