How to Replace a Pressure Washer Cylinder Head O Ring Seal - Karcher

Make and Model of Pressure Washer Used in This Video

Karcher K3 (1.601-813.0)

Part Used in This Video

Karcher Pressure Washer O Ring Seal

1. Tools required

All you’ll need are some long nose pliers, T15 and T25 screwdrivers and maybe a socket wrench and 15W-40 oil.

First, eliminate all power.

2. Remove wheels and casings

Then, remove the wheels. 

Remove plastic outer casing

You need to remove all the screws holding the plastic outer housing shell in place. These might be tightly secured, so take your time.

Remove detergent tank holder

Then, remove the four screws holding the detergent tank holder in place at the bottom. 

You can then remove the pipe hose and the tank away from the pressure washer. 

There will be two more screws that need to be removed. One on either side of the yellow housing.

3. Remove motor and internal components

Remove the detergent suction pipe hose and lift the motor casing up and out.

Remove motor casing

Remove the screws on the plastic casing with your T15 screwdriver head. You’ll then be able to pull apart the two sides of the casing and remove the motor.

Remove cylinder head

There are four T25 screws on top of the cylinder head which need to be removed. These can be extremely tight, so use a socket wrench to loosen them up if you have one, and then use a T25 screwdriver to remove them finally. 

Be careful to keep the motor standing upright as you’re removing all the screws, if there’s oil inside, it can drain out. 

Drain old oil

Once all the screws are out and the cylinder head is removed, lay the motor on its side to drain all of the old oil.

Remove connectors

To make removing the O ring simple, remove the two connectors at the bottom. Take a photo if needs to be, so you know which colour connector goes where later on.

Remove switch unit

Then, remove the switch unit from the side of the cylinder head as shown.

Remove O ring

To remove the O ring seal, simply lift it away from the cylinder head.

4. Attach new O ring and re-assemble

With your new O ring seal, place it on the cylinder head as shown. Ensuring that it’s sat flush. 

Re-attach switch unit

Now, re-attach the existing switch unit taken off a few moments ago.

Re-attach wiring connectors

The brown wire connects to the connector below the text on the motor as shown. Then, the black wire connects to the connector on the other side.

Add new oil

Now, top up the oil if needed in the cavity and place the cylinder head back on top.

Then, re-screw the four T25 screws in place on the cylinder head - making sure to keep the unit upright so no oil leaks whilst you’re re-screwing. If you have had to remove the high-pressure outlet with clamp to get to the screws, make sure to pop it back on.

5. Re-fit casings and wheels

You can now put the unit on one side of the plastic casing as shown and then re-attach the other side of the casing.

Then, re-screw all the T15 screws back in place.

You can place the motor back in the casing and reattach the detergent suction pipe hose. Then, pop the plastic housing back on. For this to attach securely and easily, you may need to unscrew the four screws with a Phillips screwdriver on the black casing at the bottom of the handle. 

Re-fit outer casing

Then, go ahead and re-screw all the screws back into the plastic outer housing. And if you unscrewed the four screws on the bottom of the handle, also re-screw these in.

Re-fit detergent tank holder

You can then re-attach the detergent tank holder and re-screw the four screws in.

Then, attach the detergent suction pipe hose back to the detergent tank. 

Re-fit wheels

Re-attach the wheels.

And that’s it, your new O ring seal inside the cylinder head is all set to go!

View all Pressure Washer cylinder head spares