My pump suddenly started knocking for about a second or two everytime I release the wand. I checked the pump oil and noticed very fine metal shavings in the oil. I had to look closely to identify the glittery metal in the milky looking oil. Is my pump at the end of its life? I recently purchased it used and am nervous I got a gd lemon. fml.
Thanks for the help.
If it’s milky it’s contaminated. If you’re hearing a knocking sound something isn’t right.
When you say glittery metal how much are you talking about? How big of pieces?
Did you change the pump oil when you bought the pressure washer?
The glittery metal is very fine. Finer than sand. I have not changed the oil.
Step one change the oil immediately in case whatever was shaved off is finished, or the oil was contaminated (crazier things have happened. Euthanasia medicine keeps showing up dog food) if you have to use it.
Step two: what kind of pump is it? Call the manufacturer and troubleshoot with their support team.
Whenever you buy new equipment always change the oil or any other fluids. All equipment has a maintenance schedule. It doesn’t matter if it’s your personal vehicle or a small push lawnmower. Take a vehicle for example. It’s usually recommended to change the engine oil every 3000-5000 miles, coolant every 100k, differential every 50k, etc. If you buy it used and, you don’t change any fluids, how are you going to know when it’s due for the fluids and oil to be changed? If it came with service records you’d be okay but a lot of times they don’t.
Your pump will have a recommended amount of hours before the oil needs changed. For all you know the oil might be 500 hours past due. Over time oil loses it’s lubrication properties which isn’t good for anything that it’s suppose to lubricate.
If it’s really old oil there probably will be some sign of metal in the oil but it should be more like grayish in the oil or super fine dust. When it’s a small amount it’s usually just normal where and tear. If you’re getting chunks or even sand I’d be a little concerned. If it’s knocking we do know something is wrong with it. I wouldn’t run it until you know what’s going on with it. Everything might be salvageable right now. Keep running it and you might be looking at a whole new pump. Depending on what’s wrong with it a new pump might be the way to go.
Save the old oil in case you take it to the shop so you can show them.
How mechanically inclined are you?
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I feel this topic could have waited until after I changed the pump oil. I panicked when I realized metal was visible in the oil and when I couldn’t find any topics on “metal in pump oil”, I assumed the worst.
It was a very recent purchase, so I haven’t got to the fluids despite that being my plan from the beginning. Before purchasing, I checked the engine oil but not the pump oil for some ridiculous reason. Probably because I’m still getting familiar with pressure washers. I do maintain all of my other small engines for lawn maintenance and wouldn’t have a problem if I needed to replace the pump. I’m competent in that regard and understand mechanics. I lack pressure washing maintenance knowledge, but I know I can figure most things out with all of the overwhelming information and videos online. The visible metal in the oil is powder like and definitely less coarse than sand. It was so fine, I had to stare at it for a while to realize why it looked glittery. The oil is a little low so with any luck, I’ll change it and hope all of my problems are over. Fingers crossed
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Sorry if I came off like I was preaching and I definitely didn’t mean to make it sound like you didn’t maintain your equipment. I enjoy working on vehicles, rebuilding engines, small engines, etc so I can get carried away talking about maintenance.
If it’s just a little bit of fine dust it’s more than likely normal wear and tear. The knocking could be a sign it’s due for a rebuild. Maybe a valve? As Squids mentioned call the manufacturer and they’ll help troubleshoot. I rebuilt a pump last summer and there isn’t much to it. The worst part was the price of the kit. If it comes to that just take a bunch of pictures along the way in case you have to refer back.
No problem at all with the preaching. It’s a good reminder.
I changed the motor oil and pump oil and the damn thing is still knocking (what I call knocking anyway). I can’t tell if the sound is coming from the pump or motor, but it is still there. I’m losing pressure also. I’m guessing it’s 25% lower in pressure. The noise gets louder and more frequent the longer I run the machine. I took a video so I’ll try to upload a you tube link here in a bit so you can listen in…
Here’s the video of the machine running Knocking pressure washer - YouTube
I was looking at rebuild kits and it looks like they are upward around $200 plus special tools to get the job done? So maybe close to $300 with the tool plus however long it would take to install the kit. If that’s what needs to happen, I probably need to come up with a model number and my plaque on my pump is blank. There are absolutely no characters on the plaque. Not sure how I’m going to identify the pump if that’s what needs to happen. I was told it was a General pump…
That’s definitely a weird sound. I wouldn’t drop money on a rebuild kit yet unless you’re willing to roll the dice that it will fix your problem for sure. I would think it would but see what others recommend. Hopefully someone will be able to tell you what it is by the sound. Maybe a valve? I recently restored an older Karcher and the kit was a little more than $300. It didn’t take any special tools though. Some of the valves were a pain to get out though. I did almost order a set of valve pliers or whatever they’re called but was able to get them out.
Look all over the pump for numbers. I’d be surprised if there wasn’t something stamped into the housing. What brand is the washer or engine? Maybe posting some pictures of the pump will help someone at least identify the brand so you can contact the manufacturer for further guidance. Have to figure out a way to find out what pump it is in order to get a rebuild kit. If all else fails you could take it to a shop or buy a new pump. How many gpm and psi?
I’d put a pressure gauge on it first and see what it’s really putting out. For not much more than $300 you could probably buy a new pump… What brand and size is that engine? Couldn’t tell from the video.
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The brand of the washer is unknown. It has a Honda GX390 and pump is 4gpm @4000psi. I can’t find a stamp anywhere on the pump- just the plaque that is washed away. I think I might get with General and see if they can identify the pump for starters. That still doesn’t really solve my problem.
What do you mean by “wallowed” out a rod? I understand where the rods are in the pump, but your terminology is throwing me off a bit. What should I be looking for when inspecting the plungers/rods? I have a gauge on order so I can have more control over the pressure. I’ve been on You Tube for hours learning more about belt drives and the benefits. I have yet to find conversion kits from a direct drive to a belt drive and from what I understand, it really wouldn’t be worth it unless I have a larger motor (Maybe 18gpm?) and a beefy Udor pump. At that point, I would be starting from scratch with a build and this machine would be the backup toy.
Wallowed makes so much more sense now that it has been explained. If I knew what the rods were doing previously, I’d understand the term without
confusion. Thanks for the detailed explanation on where to go next!
Good deal and you’re most welcome. Post up if you need help lining out some split taper bushings and sheaves for your new pump should you decide to slap it with a belt. Making up a way to tension your drive belts isn’t that hard so you just need a platform. If you need it mobile they even have bare aluminum carts with belt guards ready to go. I think I remember seeing them for about $180
