Question about Dewalt 3700 Pressure Washer

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DeWalt Pressure Washer valve broken.

I removed the pump and took a look inside my non-functional pump's cylinder to check for broken parts. Sure enough, part 355 is all busted up. However, I don't know how to get to it.
Here's the schematic:

If anybody can help, that would be cool. Thanks.

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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

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SOURCE: How do you check oil in pump on Dewalt DPD3100

There is a little window on the side of the pump to see the oil level but thats normaly the problem None of these companys make there owen pumps or engines i owen serveral power washers if you can tell me more about the problem Iwill likely know how to fix it see who made the pump and the engine and let me know pier_j

Posted on Nov 24, 2010

  • 146 Answers

SOURCE: Hi, My Dewalt 3100 pressure

The Dewalt 3100 came with 2 different pumps. The Blue Cat pump and the oil free pump that was made by DeWalt.
You may just have a bad Thermal relief Valve on the unit.

You can find the parts diagram at

Posted on Oct 01, 2011

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