Sthil MS170 Oiler

[Maurycobb]

Hello, Group!
I have a MS170 that may need a new oiler. Is this an easy repair?
Thanks for the feedback...

[hawkins111]

I would check everything else before I would mess with the pump. With the bar off check for flow, clean bar and oil hole. Tom

[Skioutty]

Most likely does not need a new pump.
More than likely it just needs a thorough cleaning. Pull off the bar and ensure the oil port is clear. also clean the groove in the bar all the way around. On the powerhead, make sure it is wiped clean as well. You can also have it clogged in the tank. Dump any oil then pour a couple of ounces of gas into the tank and slosh it around to clean it, then dump that. Refill the tank and re assemble the bar and cutter.  Side note.. flipping the bar is a good idea for even wear.

[joe_indi]

Most likely does not need a new pump. ..............

Agree 100%.
The culprit would be that little tube that connects the oil pump to the oil tank. This tube could have come off its seat enough to suck in air. This happens often in 170s and 180s. Tube is located at the bottom of the saw, beneath the handle. Push it  in using something  blunt, maybe a pencil. 

[ohiowoodchuck]

I just picked up a 170 from a friend that had the same problem. Line had come unseated from the pump causing it to suck air. Cleaned it up and reseated line, oils like a champ.

[AKDoug]

To check those saws for oil flow, I will run them without the bar and side cover at about 1/2 throttle. If you have a steady stream of oil coming from the oiler hole, then it is fine. If it has air bubbles in it, you have hose sealing issues, if there is no oil you will have to dig further.

If you have no oil, and you aren't leaking oil from the bottom of the saw, remove the clutch. Behind it you will find the drive gear for the oiler. Inspect it closely, if the plastic gear is damaged in any way, replace it.

Getting to the hose requires the removal of the handle frame. Once that is removed, the hose is readily apparent. Pull the hose and inspect the oil filter end. Clean that with gas or brake clean.

To get the pump out requires a special tool to do it right. You can do it with a bolt and pull it out, but it has a specific depth to set it, which the special tool does. Rarely is the pump the issue. It is usually the other parts that are the problem.