Husqvarna 550XP Mark II Oil Pump Assembly

This Husqvarna 550XP Mark II oil pump assembly replaces the pump that meters bar oil to the chain on one of the most common ground saws in tree work. When the chain runs dry and the oil passages are clear, the pump is the next thing to look at.

Diagnosing an oiling problem

A 550XP Mark II gets used hard: limbing, bucking, and cleaning up after a takedown all day. When the bar starts smoking or the chain dulls fast, first pull the bar and clean the oil hole, the bar groove, and the area around the clutch cover. Check the tank filter and oil hose for clogs or cracks.

If oil still does not show when you hold the running saw over a light-colored stump, the pump is likely worn or damaged and this assembly is the fix.

Bar oil that is too thick in cold weather can also slow delivery, so match your oil to the season before blaming the pump. A winter-grade bar oil flows better on frosty mornings.

Installing the pump

The pump sits behind the clutch, so plan on removing the clutch with the correct tool and a piston stop. Inspect the worm drive and oil line while it is apart and replace anything worn. Run the saw and confirm a steady oil line before it goes back on a job.

Confirm the part number against your saw's model and serial plate or the manufacturer's parts lookup before ordering, since parts can change between production runs. Browse more chainsaw parts for the 550XP.