How to Winterize an Electric or Gas Pressure Washer Pump

Winterizing a pressure washer pump is fairly easy. If you live in an area that experiences below freezing temperatures, you should winterize your pressure washer pump. There’s nothing worse than firing a power washer up and getting nothing but a small dribble of water out of it. Naturally, this will only happen when you need it the most!

I’ve ruined at least one (I wont confess to any more than one) pressure washer by not winterizing it. I ended up replacing the pump on it. That was a royal pain in the butt and an expensive fix! It could have been prevented but for sheer laziness on my part. Now, I make sure to winterize my power washer every year!


General Maintenance for Power Equipment

This article is mainly focused on preserving the pressure washer pump. But it wouldn’t be complete without a mention of some of the other items you should tend to. This is especially true of a gas pressure washer. If you have an electric pressure washer, you can skip this section. Bit if you have a gas pressure washer. Take a moment to read through this.

Gas Pressure Washer Winter Maintenance.

I’ll make this short and sweet. You need to take care of the fuel system. this is especially if you use ethanol gasoline. The easiest way to do this is to run the gas pressure washer until the gas runs dry. If you have to for any reason leave gas in the system, make sure you have a good quality preservative such as Sta-Bil or Star-Tron fuel preservative. But the safest bet is to completely drain the gas out of your gas pressure washer.

Here’s a link to an excellent article on Popular Mechanics on storing small gas engines for the winter. PM Small Engine Winter Storage

The other item you should take care of is the engine oil. I make it a point to change the oil on all my small engines annually. Typically, I’ll do this in the fall as part of routine maintenance. Small engines like the ones you find on gas pressure washers are a pain to change the oil on. The plug to release the oil is typically on the bottom of the block. Worse than that, there is usually no clean way to capture the oil as it drains.

Still, it’s worth changing the oil annually. I’ll have to post an article on changing small engine oil soon. There’s a few tips and tricks worth writing post about on how to drain the oil from these engines without creating an environmental disaster. In any event, lets go on to winterizing the pressure washer pump.

Off the Shelf Winterizing Options

There are a number of off the shelf options you can use to winterize your pressure washer. Some of them are ingenious! Briggs and Stratton makes one that comes in an aerosol can, you simply screw it on to the the inlet depress the trigger and it will inject foam into your system. Others are a little less so. Typically they come in a bottle that you thread onto the water intake and then squeeze into the system.

I like to leave the preservative in the pump. The screw on bottle poses a bit of a challenge here. If you leave it on, you’ll have fun tilting the power washer back to move it. I tried one of these once and it turned out to be a bit of a pain to move the pressure washer around. The screw on bottle would drag on the floor and came close to coming off a few times.

The off the shelf options aren’t terribly expensive. They usually run between five and ten dollars. Some of them are single use. Most of them will get you several years of use. I prefer to make my own though.

Why Make Your Own Winterizing Fluid?

Granted, the off the shelf options are fairly inexpensive. They are also fairly easy to use. So why make your own? To start, you can make your own for about the same price as a commercially available pressure washer pump preservative. The key differences are that you will know exactly whats in it. The anti-freeze fluid I use is environmentally safe. If you happen to spill some, you won’t have to worry about pets accidentally getting into it.

I also use Johnson 4618 Radiator and water pump lubricant. I reviewed the MSDS for this product and at most, it’s a mild irritant so feel comfortable using it in the mix. An additional benefit is that for the same price as a commercially available product. You will have enough to last for a long time. At least 5 years and probably much more!

What you will need to Winterize your Pressure Washer Pump

Here’s a quick list of the items you’ll need to winterize your power washer pump.

  • RV Winterization fluid (1 gallon).
  • Johnsons Radiator Anti-Rust and Water Pump Lubricant.
  • Old Discarded hose with a male end
  • A funnel to fit into the hose and a hose clamp

The RV antifreeze is designed to be used in potable water systems. Mot of these are made with propylene glycol. The same ingredients you’ll find in e-cig liquids. As a matter of fact, it’s the same component I used in my DIY Ice Pack Article. Its a safe alternative to other anti freeze compounds which is why it can be used in systems for drinking water. You can pick this up at a Wal-Mart for about $2.50

The Johnson’s Radiator and Water Pump lubricant will help preserve your pressure washer pump in a few different ways. First, it prevents the internal components of the water pump from corroding. Second, it lubricates the same components. You can find pressure washer pump oil sold commercially. For a homeowner, I think the best way to lubricate the pump is through a good winter prep.

Get the Water Out of the Pressure Washer Pump

To do this, disconnect the pressure side hose and make sure there is no supply hose connected to the pressure washer. Make sure the engine switch is set to off. Pull the starter rope a few times. This will cycle the engine and expel water that is left in there. If you have an electric pressure washer, you can skip this step. Once you get the winterizing fluid in there it will dilute the water with the mixture.

You also want to get the water out of the pressure side hose. There’s a few ways to do this. You can lay it out flat and pick one end up then walk it along. You can also coil the hose in a loop. Turn it over in a circle as many times as there are loops and that will get the water out. MY favorite method is to use compressed air. Blowing compressed air in one side will quickly get the water out of the hose.

A good idea at this stage is to use silicone grease to lubricate the ends of the high pressure hose. Silicone grease will not harm the o-ring on these hoses whereas petroleum grease will.Now is also a good time to inspect the o-rings for signs of wear. If they need replacing, you can readily order some on Amazon by following this link: O-Rings

Prepare your Pump Anti-Freeze and Lubricant

The next step is to get the power washer pump anti-freeze and lubricant ready. This is fairly simple and straight forward. Pour 12 ounces out of the RV anti-freeze into a container and reserve for later. You can now pour the entire contents of the pump anti-rust and lubricant into the RC anti-freeze container. The Johnson pump lubricant is water soluble and is milky white. Tip the container over a few times to mix it. You should end up with a pink milky solution.

Prepare the Hose and Funnel

This step shouldn’t take long. You want to cut the hose so it is long enough to attach somewhere along the top of the power washer. The end with the male threads will be attached to the power washer inlet. The cut end will be at the top. Slip your hose clamp over the cut end and insert the funnel into that end. Tighten the clamp to hold the funnel in place. Last, attach the hose to the power washer using a tie wrap or string (or wire, basically, anything that’s handy).

Add the Pressure Washer Winterizing Fluid

Once you have fluid coming out of the pressure port, you can attache the pressure washer hose (high pressure hose). At this point you will want to add more winterizing fluid to the hose funnel setup. Make sure the engine is set to off and pull the start cord a few times. This will cycle the pump and push the fluid through the system. Additionally, it will work the lubricant in the pump seals, conditioning them.

If you have an electric pump, you can pour your fluid in and let gravity do it’s job. Keep pouring until the level stays steady. Alternatively, you can also cycle the pump on. If you chose to do that, be extremely careful. Remove the nozzle and handle from the other side of the hose and put the hose in a container to catch any overflow. Use short bursts to cycle the fluid through the system. You’ll find that the pressure at the bare end of the hose without a nozzle is surprisingly low.

Leftover Pressure Washer Pump Fluid

You still have around 12 ounces of RV anti-freeze set aside. Pour that back into the gallon containor. I dont think the differene in dilution will make much of a difference for future use. I wold carefully mark the containor as well so that you (and enyone that might encounter it) know its for Pressure washer storage.

A Final Word on Pressure Washer Storage

It doesn’t matter who makes your pressure washer. It could be Homelite, Craftsman, Troybilt or any other manufacturer. Mine happens to be a Homelite with a Honda engine and pump, so I suppose it’s a Homelite-Honda pressure washer. Regardless, any brand or make will benefit from a good winterizing.
You’re basically done and can store your power washer away until the warm season rolls around. When that does you can drain the fluid from the system and reclaim it for later use. Or you can safely dispose of it at a local convenience center.

Below are affiliate links to the pump lubricant and a similar RV antifreeze I used in this project:

You can also watch the video version of this article below: