Husqvarna Decompression Valve for 395XP

The Husqvarna 395XP decompression valve bleeds off compression while you pull the starter, so the big saw turns over without kicking the rope out of your hand. When the valve sticks open, leaks or gets damaged, the saw loses power or gets hard to start, and a new valve is the cheap fix.

When the valve needs replacing

The 395XP is a big-wood saw, and it makes serious compression. The decompression valve is what lets you start it on the ground or on a stump without a fight. Press the button, pull, and the valve pops closed on the first fire.

Signs of a bad valve: the button won't stay down, the saw loses power and feels down on compression, or you hear a hiss or see blow-by around the valve body. Carbon buildup can also hold it open after a long day of bucking.

A healthy valve matters more than it sounds. Without it, a 395XP is tiring to start all day, especially cold or when you are restarting it twenty times while bucking up a big removal. Starter ropes, pawls and handles also wear faster when they fight full compression. If you run a 395XP as the big-wood saw on the truck, it is worth keeping a spare valve in the parts box.

Installing it

Remove the top cover, clean around the valve so grit doesn't fall into the cylinder, and unscrew the old valve with the right size socket. Thread the new one in by hand first, then snug it to the torque in the Husqvarna service manual. Don't overtighten into the aluminum cylinder.

Run the saw and check that the button resets on startup. Browse more Husqvarna chainsaw parts if you are refreshing the whole saw.