I need to pressure wash belt side of my engine

Get some of the foamy engine bright that is sold in the stores, get about 3 cans. Then don't use a pressure washer, just a regular garden hose with a sprayer nozzle. Run the engine a bit to start warming it up, shut it off, then douse it heavily with the cleaner. Now let it soak a while. Then rinse the belt area off and start the engine then rinse the rest of it off. Try to do this over gravel or with a tarp under the engine room, then toss some kitty litter or absorbent under it to catch the run-off. Once it's all rinsed off shut the engine off and leave the hood open to let as much evaporate as possible. If you have a fan that you can set to blow on the engine that also helps.
I've washed off a lot of engines this way. Using a pressure washer can get water into places it shouldn't get because it can blow water past seals and gaskets, the lower hose pressure generally doesn't. It can also show you if you have a vacuum leak somewhere, listen for the engine sound to change and steam to come out the exhaust if a leak draws in water.

You should be able to wash around the hose without a problem. Water will wrap around it and rinse the oil off. I don't remove parts if at all possible.

You are welcome.