pressure washer problems

[bob_wood]

I have the 5.5hp version of the same washer. Mine just started doing the same thing. It would start, run and I'd bring it up to speed. As soon as I pulled the trigger on the spray handle, it would seem to run out of gas.

I checked everything. I rocked the unit to stir the fuel then dumped it into a drain pan. Put fresh gas and tried it again. Same thing. I then pressurized the tank (to about 4-5psi) and worked the fuel shut-off valve back and forth about 5-6 times. Fired it up and it's been running good since.

The only thing that I can figure is there must have been some crud or gum clogging up the shutoff valve. Try it. Your mileage may vary.

tonight after work i started the engine and tried the unit operation. seems my symptoms have changed a bit. the engine dies even without trying to spray. So I drained the fuel and put in fresh gas. Same problems / symptoms so i disassembled and disconnected the pump from the engine. Now the engine seems to run fine. So I guess the pump load on the engine is the problem but Im not sure how to go about troubleshooting... Ken, how did you pressurize the tank? just curious

bob

 

[bob_wood]

Hiya,

I would look at the governor and carb system before I pulled the pump apart. When you trigger the wand you cause more load on the engine.

If the gov doesn't respond to the additional load and open the throttle automatically, the engine will stall.

If the main jet is plugged in the carb, when the throttle is opened by the governor, the mixture will lean out and stall the engine.

My 2 cents,

Tom

I unhooked the pump from the engine and the engine seems to run fine but the pump load is somehow killing the engine. Guess I should be troubleshooting this problem with the pump hooked to the engine. With the pump hooked up, I do see the choke lever go to full choke when the engine stalls.. any idea what That means? Does it on its own. Thanks for the input Tom

bob

 

[bob_wood]

correct me if i'm wrong, but the pump is still turning even when the trigger on the wand is not pulled. it just pumps the water in a circle through the unloader valve. then, when you push the trigger, the unloader valve closes and the liquid is diverted through the wand.

soooo... doesn't that eliminate the pump as the problem? could be an obstruction somewhere between the unloader valve and the nozzle or, as mentioned above, a problem with the engine - carburation, governer, etc.

amp

sorry for the confusion ampsucker, my engine is stalling even Before i try to spray. engine runs for a short time , then stalls. sometimes I can spray for a short time then engine stalls. sooooooo guess my problem could be the engine OR the pump. I Did try some fresh gas....no help. Thanks for your input.

bob

 

[CCWKen]

Ken, how did you pressurize the tank? just curious

Bob, I have small hand pump with a low pressure gauge. It's used to check the "pop-off" pressure on some carburetors. I also have a flanged plug with a tube that's used to test fuel tanks. Insert the plug into tank filler opening and attach the pump to the tube. But... You don't have to get that exotic or have special tools.

Tape a baggie over the filler opening, punch a hole in the center and blow! Just don't let your neighbors see you doing this!

 

[bob_wood]

well I'm afraid this problem may have to be fixed by someone with more expertise than I have. Thot I would try to do what I could ... Thanks alot for the input Ken. My neighbors cant see my workshop !!

Bob

Bob, I have small hand pump with a low pressure gauge. It's used to check the "pop-off" pressure on some carburetors. I also have a flanged plug with a tube that's used to test fuel tanks. Insert the plug into tank filler opening and attach the pump to the tube. But... You don't have to get that exotic or have special tools.

Tape a baggie over the filler opening, punch a hole in the center and blow! Just don't let your neighbors see you doing this!

 

[bigdad]

I have put two fuel pumps in a portable generator generator in the last year because of leaks. I finally approached a small engine repair mechanic and he said that it's the ethanol in the gas. I stopped using that stuff. So you're right.

The carburetor may need rebuilding. The ethanol content in the gasoline today is wreaking havoc on small engines and the rubber parts in them. Also-the ethanol attracts water so fuel does not last as long as it used to even with stabilizers.

 

[J_J]

Bob,

I can almost bet that your trouble is the unloader valve. I have had similar problems. Either replace it, or try and take it apart and clean the seat, spring, etc. You can tell if the unloader is working by the temp of the water. If it is warm, then it is recirculating like it is supposed to. On a stuck unloader, the water has no place to go, so it puts a stop load on the pump, and henceforth kills the engine. Take off the unloader valve and see if the engine will run. You could also put a 3500 psi gage on the output before it goes to the hose and see what the pressure is. You should know that the running pressure is never at the rated PSI of the pressure washer. It may spike up to the rated pressure just before the unloader valve releases the pressure. That valve is a pressure relief and an unloader built together.

 

[J_J]

This is an unloader valve. :Yours may look a little different, and may cost less.

Northern Tool + Equipment | Error


http://www.the-power-washer-advisor.com/unloader-valve.html

 

[bob_wood]

I have put two fuel pumps in a portable generator generator in the last year because of leaks. I finally approached a small engine repair mechanic and he said that it's the ethanol in the gas. I stopped using that stuff. So you're right.

thanks for the input Bigdad. Seems like everything I own is running " rough " this year. I'm beginning to believe the gasoline is part / all of the problem.

Bob

 

[bob_wood]

Bob,

I can almost bet that your trouble is the unloader valve. I have had similar problems. Either replace it, or try and take it apart and clean the seat, spring, etc. You can tell if the unloader is working by the temp of the water. If it is warm, then it is recirculating like it is supposed to. On a stuck unloader, the water has no place to go, so it puts a stop load on the pump, and henceforth kills the engine. Take off the unloader valve and see if the engine will run. You could also put a 3500 psi gage on the output before it goes to the hose and see what the pressure is. You should know that the running pressure is never at the rated PSI of the pressure washer. It may spike up to the rated pressure just before the unloader valve releases the pressure. That valve is a pressure relief and an unloader built together.

Thanks Alot J_J. I havent had a chance to get back to my pressure washer problem ... worked 7 days this week, but I have been thinking about what to do. I have suspected that the unloader valve may be my problem but must confess I dont know crap about an unloader valve or how to go about fixing one. Dont mind replacing it if that is what needs to be done but hate to spendthe money if that isnt " it " . The advise and info that you have given me is Very helpful. Understand the unloader valve is " preset " and shoud not be changed ? I will take it off the pump and take it apart to see if it is stuck or clogged up.

Bob