small engine repair/pressure washer issue

[gamorg02]

hey guys,

didn't know if anyone is good with small engines, specifically pressure washers?

picked up one from my grandparents which had been sitting for a few years. to my surprise the engine runs well, starts right up and doesn't hiccup, stumble or anything. can start on 'run' after being started on choke.

the problem is with the 'pump' i believe. here are the symptoms:

1. start the engine on 'run'. press the wand in, no pressurized water.

2. start the engine on 'choke'. engine starts at less than 'run' rpms. press wand in and get 50% pressurized. while keeping wand pressed, turn engine to 'run' and now you get 100% pressure. if you let go of the wand and press it again, you go back to no pressurized water

3. engine off. press wand in. start the engine on 'run'. 100% pressure until you let go of the wand.


it sounds like to me it may be a stuck 'unloader' valve? or someone else mentioned a check valve. i'm gonna dig into it soon but didn't know if anyone else had any luck. found someone online with the SAME issue click here , but of course no solution is listed.


anyone have any ideas?

thanks in advance!

 

[CaptainKyle]

Sounds like an unloader valve to me which some have check valves built into them. I used to work on these things a bit & parts can get expensive for them quick. What brand of pump does it have & is it one of them mounted underneath the unit or off to the side ?

 

[gamorg02]

its a craftsman with a kretcher engine (spelling?). not sure what type of pump it is though, its under the unit..

heres some exploded views from the manual if it helps? Looks like the unloader is pretty accessible. and is # 23

 

[CaptainKyle]

Most of them bottom pumps are pretty cheesy. You can try the unloader but if it gets into any thing else unless the parts have came down in price over the years its gonna get expensive quick. I have not checked the prices on parts for them lately so they might be better than they used to be.

 

[gamorg02]

what should I look for once I get in there? Looks like the check valve section is pretty easy to drop and check out too. i found the check valve kit for $30 i think with the gasket..

 

[CaptainKyle]

I would drop the check valve first it might just be corroded there is a chance that you might could just clean it up & make a new gasket. Look for pitting corrosian etc.

 

[gamorg02]

i'll do that tonight... thanks for the help kyle. can i just use rtv gasket maker on it?

 

[CaptainKyle]

You can try it if you do use the rtv let it sit overnight to cure good. I cant gaurantee it will hole up there as I have never tried to use it in that application.

 

[gamorg02]

i hear ya. maybe the gasket will come up in one piece! haha. i might try the unloader first as it doesn't use a gasket and if its obviously stuck or something...

 

[RaWarrior]

My pressure washer does that too...I got for free as a reject from work. The vertical shaft ones are pretty cheap and don't last long...we went through three of them in a season at the marina before the bossman finally got wise and bought one with an oiled, horizontal triplex Cat pump that actually works.

The wand on mine has a twisty thing at the end to adjust the spray. I just hold the trigger(no pressure), twist it to "soap"(hear the motor load up a bit), then twist it back to max(good pressure). I have a zip-tie in a loop that I can slide up over the trigger to hold it down.

You might try turning down the input hose's valve though. I found doing that/supplying less pressure to it makes it work better, less back pressure for the valve to pop against.

 

[gamorg02]

so i have the pump apart and honestly not really sure what i'm looking at here. nothing seemed corroded or not working. all the check valves appear to work the same (couldn't test one of them)

the unloader system looks good, but i couldn't get the female piece out (any ideas?)...

i found some ebay sellers selling refurb pumps for $75, might look into that...

 

[CaptainKyle]

I am not sure with out seeing that pump in person what kind of seals it has around the ceramic pistons to make the pressure or if the pistons are even ceramic in that cheap pump. If the seals are going bad around the ceramic it will have pressure to start with & then die off. Its really hard to say with out looking at it. A pump for 75 bucks is cheap but then you get what you pay for. Cat or Comet or Hotsey are some of the premier pumps but they cost more than that whole pressure washer.

 

[gamorg02]

I am not sure with out seeing that pump in person what kind of seals it has around the ceramic pistons to make the pressure or if the pistons are even ceramic in that cheap pump. If the seals are going bad around the ceramic it will have pressure to start with & then die off. Its really hard to say with out looking at it. A pump for 75 bucks is cheap but then you get what you pay for. Cat or Comet or Hotsey are some of the premier pumps but they cost more than that whole pressure washer.

i can take pics! haha. the pistons in the pump are steel i think, definitely metal. the seals look okay as well.

pressure does NOT die off once its running at all, it runs strong, its just getting the system pressurized.

also yea those are 'cheap' pumps, but they come with a 1 yr warranty and the power washer was free up until this point.

 

[CaptainKyle]

With a year warranty & if 75 bucks is all you put in it that aint bad. I am more familiar with the good pumps my boss used to tell me these the cheap ones were not worth messing with so we did not do a whole lot with them.

 

[gamorg02]

good point... i'll do a bit more research but it might be worth just getting the pump as you said. i'd b ea lot more confident if i found like 1/6 check valves sticking or something ya know?