How To Start A Pressure Washer

Look, I get it. You bought a pressure washer, or you dragged one out of the garage that's been sitting since last fall, and now you're standing there pulling the cord or flipping switches like it's a puzzle. You're not alone. After twelve years of running a mobile detailing business out of a Sprinter van (that's Rosie, my 70-pound lab mix, riding shotgun and judging my nozzle choices), I've started more pressure washers than I can count. I've also watched a $99 electric unit strip its plastic gears on the third use, and I've flooded a gas engine so bad I had to wait twenty minutes for it to dry out. This guide covers the right way to start both types, plus what to do when they won't cooperate.

Product	Price	Why it won	Why it lost
Simpson Megashot 3200	Check price	Honda GC190 starts first pull, CAT pump, detergent works	Stock hose is only passable
Sun Joe SPX3000	Check price	Cheap, easy electric start, siphons soap properly	Axial pump, dies after two seasons
Ryobi 2300 Gas	Check price	Starts reliably, fine for light use	Hose kinks, cheap pump, wheels are useless
Kärcher K5	Check price	Decent pressure for electric	Plastic gun feels like a toy, fittings are cheap

Why you should trust me

I'm Tony. I've owned three pressure washers that taught me what's worth your money and what's a $150 lesson in frustration. My current rig is a Simpson Megashot with a Honda GC190 engine that starts first pull even after a winter I forgot to winterize, which cost me a $150 pump replacement I still don't want to talk about. I've pressure washed more driveways, decks, and boat hulls than I can count, and I've burned through enough nozzles and fought enough kinked hoses to know exactly what makes these machines start, run, and die.

How I picked

My criteria for "how to start" advice is simple. Does the engine or motor fire up consistently? Does it stay running once it's going? And does the pump hold pressure without sputtering out after ten minutes? I've run units until the engine was hot and the soap was gone. I've also read what owners report, because the guy who posts a photo of his dead pump on Amazon is the real hero of this industry. Those reports tell you more than any spec sheet.

How I tested

I've started gas engines cold, warm, and after months of sitting. I've tested electric units straight out of the box and units that were left in a shed over winter. I've measured time from first pull to steady spray, and I've timed how long detergent systems keep drawing soap before they give up. The numbers that matter are GPM, not PSI. PSI is penetration. GPM is what actually cleans. A unit with high GPM and moderate PSI will outperform a high-PSI, low-GPM machine every single time.

Starting a gas pressure washer

Here's the deal with gas units. The Honda GC190 on my Simpson is the gold standard. First pull, every time, even after sitting for months. That's not luck. That's a proper choke, a primed fuel line, and an engine that's built right.

First, check the oil. I know it sounds obvious, but you'd be amazed how many people skip this and then wonder why the engine seizes after ten minutes. The dipstick is right there. Pull it, wipe it, check the level. If it's low, top it off. If it looks like chocolate milk, you've got water in the crankcase and you need to drain it before you even think about starting.

Second, check the fuel. If it's been sitting since last season, drain it and put in fresh gas. Old gas goes bad in about thirty days, and it'll make your engine sputter and bog down no matter how many times you pull the cord. I run non-ethanol fuel in mine, and it's worth the extra trip to the station.

Third, turn the fuel valve on. It's usually a little lever near the bottom of the tank. If it's off, you're pulling the cord until your arm falls off and nothing's going to happen.

Fourth, set the choke. Cold engine, choke closed. Warm engine, choke open. If you've been running it and it stalled, don't choke it again. That's how you flood it.

Fifth, pull the cord. Firm, fast, full stroke. Not a timid little tug. You're not starting a lawnmower with a rope. Pull it like you mean it.

Once it fires, ease the choke open as it warms up. If it sputters and dies when you open the choke, close it halfway and let it run for another minute. Then try again.

Starting an electric pressure washer

Electric units are simpler, but they have their own quirks. The Sun Joe SPX3000 is the one everyone starts with. At $120, it's cheap, it works, and it'll die after two years, but you got your money's worth.

First, make sure the unit is plugged into a GFCI outlet. Most electric washers trip a regular outlet if they're drawing too much current, and then you're standing there wondering why nothing's happening when the breaker's just popped.

Second, connect the garden hose to the inlet and turn the water on. Here's the thing: never run an electric pressure washer without water flowing through it. The pump relies on water for cooling and lubrication. Run it dry for thirty seconds and you've cooked the seals.

Third, squeeze the trigger on the gun to bleed the air out of the line. You'll hear the pump prime and then settle into a steady hum. If it's sputtering, you've still got air in the line. Keep the trigger open until the stream is steady.

Fourth, engage the trigger lock and plug in the unit. Some models have a power switch on the unit itself. Flip it on, unlock the trigger, and you're spraying.

Why your pressure washer won't start

Let's talk about the problems, because that's what you actually came here for. The most common issue is a flooded engine. You pulled the cord fifteen times, it never fired, and now the spark plug is wet with fuel. The fix is simple. Close the fuel valve, open the choke all the way, and pull the cord ten times with the throttle wide open. That clears the excess fuel. Then reset the choke and try again.

The second most common issue is a clogged carburetor. This happens when you leave gas in the tank over the winter and the ethanol absorbs water and turns into varnish. The fix is either a carburetor cleaner or a rebuild kit, depending on how bad it is. I've rebuilt more carbs than I care to admit, and it's not a fun job, but it's cheaper than a new engine.

The third issue is a dead spark plug. Pull the plug, check the gap, and if it's fouled, replace it. They're about eight bucks and they take two minutes to swap.

The fourth issue is a tripped GFCI on an electric unit. Check the outlet, check the breaker, and check the unit's own reset button. I've seen more than one person panic over a unit that just needed its reset button pushed.

Our pick: Simpson Megashot 3200

This is the one I tell everyone to buy. It's the sweet spot. Not the cheapest, not the most expensive, just the right machine for anyone who wants to wash their driveway without replacing it every year. The Honda GC190 starts first pull even after sitting for months. The CAT pump is what the pros run. Mine's been going for four years and it still sounds like the day I bought it. The stock hose is passable, not great, not garbage, but I replaced it with a Flexzilla anyway. The detergent system works, which is rare. At $450, it's $56 a season if it runs eight years. A $120 Sun Joe that dies after two years is $60 a season. Do the math.

Flaws but not dealbreakers: The wheels are cheap and they're not great on gravel. But you're not buying this to race it.

If you're a homeowner who wants to wash a driveway, a deck, and a car without swearing, this is the unit. Rosie approves, and she's got high standards for equipment.

Budget pick: Sun Joe SPX3000

Everyone starts here. It's cheap, it works, and it'll die after two years. But at $120, you got your money's worth. The reviews are full of people saying "great for a patio, garbage for a driveway," and that's exactly right. It's an electric unit with an axial pump, so you know the deal. The pressure is fine for light work, the detergent system actually draws soap, which is more than I can say for some $500 units, and the hose is short but manageable. If you're washing a car and a small patio, this is fine. If you're doing a driveway, you're going to be there all day and you'll wish you'd spent the extra $300.

Flaws but not dealbreakers: The plastic fittings crack if you overtighten them, and the hose is only 20 feet. But for $120, you can't complain too much.

This is for the person who washes their car twice a year and has a patio that needs a once-over. It's fine. Just know what you're buying.

Upgrade pick: Ryobi 2300 Gas

Home Depot special. It's the washer everyone buys because it's on the shelf and it's the right price at $299. The reviews are mixed, with "fine if you're not a heavy user" being the consensus. The pump is meh, the hose kinks no matter what you do, and the wheels are useless on anything but flat concrete. But it starts, it runs, and it'll get your driveway clean if you're patient. My first gas unit was a Ryobi, and it did the job. I just got tired of fighting it.

Flaws but not dealbreakers: The hose kinks constantly, and the pump is axial, which means it's a countdown timer. It'll work for a season or two, then it'll blow a seal and you'll be buying a replacement for the price of a new unit.

This is for the guy on a budget who knows he'll only use it a few times a year. It's fine. But if you're going to use it more than that, save for the Simpson.

The competition

The Kärcher K5 at $300 is overpriced for what you get. The plastic gun feels like a toy, the fittings are cheap, and the wand rattles. Customer service is great, but you shouldn't need to call them. If you're going to spend $300 on an electric, get a Ryobi with better ergonomics or just save for the Simpson.

The Westinghouse 2500 is surprisingly good for the price. Quiet, starts easy, decent pressure. The reviews call it "a sleeper," and that's accurate. If you see one on sale, grab it.

Generac? Avoid. Just avoid. The reviews say parts are impossible to find and the pump dies. There's no reason to buy a Generac when Simpson exists.

The bottom line on starting

Starting a pressure washer comes down to three things. Fuel, choke, and water. Gas units need fresh gas, the right choke position, and a firm pull. Electric units need a GFCI outlet, a connected hose, and the trigger squeezed to bleed the air. If you do those things, the machine will start. If it doesn't, check the spark plug, check the carburetor, and check the GFCI.

And for the love of everything, winterize your unit before you store it. Run antifreeze through the pump or plan to replace it come spring. There's no third option. I learned that the hard way with a $150 pump replacement on my Simpson, and I don't want you to make the same mistake.

The Simpson Megashot is what everyone recommends, and for once, everyone's right. Honda engine, CAT pump, detergent that works. It's the unit I'd buy again tomorrow, and the one I tell every homeowner to start with. If you're going to spend money on a pressure washer, spend it once and spend it right.

How To Start A Pressure Washer