Pressure washer woes

[PTmowerMech]

GC160 Honda engine. XR2600

Was brought in with something that I believe to be kerosene in the tank, fuel lines and carb. Cleaned all that out a few times. Got it to running, although it runs pretty rough. A few times now, when I let off the trigger, it bogs the engine down to the point it dies.

After getting everything cleaned out good, I removed the hose (to the wand) and just let it idle for about 20 minutes.

Is this a carb issue?

 

[Scrubcadet10]

Maybe an issue with the unloader valve? I've heard of them causing similar symptoms... but never worked on one with that being the case.

 

[PTmowerMech]

If they stick, doesn't that cause them to lose pressure? I'm not sure if this has an unloader valve. Not one that I'm accustomed to seeing.

 

[ILENGINE]

I haven't seen a pressure washer without some version of unloader valve and I work on over 50 per year. I think your issue is more related to the run side of the system and not so much the pump. Letting go of the trigger put a serious load on the engine until it goes into bypass.

 

[Hammermechanicman]

Change the spark plug
Unhook the hose to the wand from the pump and turn on the water. Does the engine run good with the light load?
Hook up the hose and run it. does the pressure washer have good spray pressure?
When you let off the trigger in a couple seconds the unloader should start to bypass. If the unloader is stuck closed it will kill the engine very abruptly in a second or so after letting go of the trigger. If engine labors and runs rough you have an engine problem. I have seen more than one honda powered pressure washer die when under a load from a fouled spark plug.

 

[PTmowerMech]

Change the spark plug
Unhook the hose to the wand from the pump and turn on the water. Does the engine run good with the light load?
Hook up the hose and run it. does the pressure washer have good spray pressure?
When you let off the trigger in a couple seconds the unloader should start to bypass. If the unloader is stuck closed it will kill the engine very abruptly in a second or so after letting go of the trigger. If engine labors and runs rough you have an engine problem. I have seen more than one honda powered pressure washer die when under a load from a fouled spark plug.

I'd say this NGK plug that's in it doesn't have 30 minutes on it. Including what time I've used it.

It runs like a top without the hose connected to it. The pump sprays the water out a good 20ft.

 

[Hammermechanicman]

If you connect the hose and let off the trigger does it kill the engine?

 

[PTmowerMech]

If you connect the hose and let off the trigger does it kill the engine?

Yes, Not every time. But most of the time.

 

[Hammermechanicman]

Usually when the unloader sticks closed (doesn't unload) it will kill the engine. Does it make the engine labor hard or does the engine run rough? Even under heavy load the engine should run smooth. If engine runs rough under a heavy load something wrong with the engine. Most unloaders can be disassembled, cleaned and o rings lubed with silocone faucet grease.

 

[PTmowerMech]

Usually when the unloader sticks closed (doesn't unload) it will kill the engine. Does it make the engine labor hard or does the engine run rough? Even under heavy load the engine should run smooth. If engine runs rough under a heavy load something wrong with the engine. Most unloaders can be disassembled, cleaned and o rings lubed with silocone faucet grease.

I found, removed and free'd up the unloader. Well, freed it up somewhat. And at first, it seem to do ok. But after a few times, I just went right back to stalling out the engine.
Engine seems to run fine.

I might try backing out the nut, to put less tension on the unloader spring. I'm not sure how to set the tension on those.

When you screw the end cap on just a few threads, which holds the spring to the unloader, there's no way that unloader is going to open. I pressed with all my might, and couldn't get the spring to compress.