Karcher gas powered pressure washerI was using the Kärcher G2700 gas powered pressure washer the other day, when it gradually started running rougher and finally died.

I did a quick check on the most likely causes, but couldn’t find anything that would have caused the malfunction. It was getting the spark, and fuel. When I tried to start it again, it backfired violently, when pulling the starter cord.

A quick Internet search suggested either timing being off, due to sheared flywheel key, or the compression release mechanism broken, or valves out of adjustment.

I took the flywheel off, and checked that the key was ok. The ignition timing is not adjustable on these motors. So that wasn’t the issue.

Cracked rocker arm and bent lifter rodToday I finally had time to dig deeper. I took the overhead valve cover off and noticed that the exhaust valve lifter rod was out of place, and it was also slightly bent.

The rocker arm had cracked and was bent at the crack. I also discovered that the exhaust valve was seized in close or almost closed position.

The intake valve lifter rod was also bent quite a bit, but still in place.

I straightened out both lifter rods, oiled up everything, and tapped on the exhaust valve until it loosened up.

Rocker arm crack weldedI welded the crack on the rocker arm, and assembled everything, and adjusted the valve to rocker gaps.

I changed the oil, and tried to start the pressure washer. It started up right away and ran great!

I pressure washed my drive way, and the pressure washer ran great the whole time.

Overhead valve rocker assemblyI suspect that the cause for the failure was not changing the engine oil sooner.  I haven’t used the pressure washer that many hours, but other people have used it, and the pressure washer must have run many more hours than I thought.

Oh well, it is running great again, and the cost of the repair: zero! 😊.