Finally got around to the 044 vent. I was not able to punch the bent into the oil reservoir. The pictures show the difficulty. Looking into the inside it looks like there are internal case parts that obstruct the vent from getting into the case. Also there is what looks like a metal flange or something at the bottom of the vent port. It may be possible to punch it through on other saws but I don’t think it possible on the cases I have. One is a Stihl and the other a Huztl. Pictures below. On the internal picture you can see part of the vent is under what seems to be the case wall.
The Stihl was ruined by running without oil (not by me). The Huztl was low cost replacement assembly to get the 044 running again. I cut beams so wanted something a bit beefier saw so squeaking by with the Hutzl assembly. The Huztl worked for a short time but got damaged when an alignment pin vibrated into the clutch area. It is being replaced by Huztl.
The rebuilt saw had a big oil leak. I took out the vent and think it is plugged. I can’t blow air through it. I can with the Stihl original although it is hard to blow air through. I’ve heard that a plugged vent will cause an oil leak. I’m not sure but I guess that would be due to pressure buildup causing oil to leak out anywhere it can to relieve pressure. I opened the oil cap to relieve pressure a few times but it still leaked. But that might have been due to oil already leaked into the case internals and dripping out later.
A weird thing that happened when the pin was inside the clutch area. The oil leaking out turned black. The leak was not out of the chain oiler port but someplace else. I’ve never been able to locate the leak. I had replaced the oiler tube and put in a new oiler but the leak was the same. I was test running the saw without a bar. The leak was the same with proper color oil. Then the pin got into the clutch area, the oil started turning black. This happened fairly quickly. The oil ran then the clutch broke and the E-clip and sprocket came off.
My puzzle is what caused the oil to turn black. The pin or clutch broken piece put a hole in the was of the clutch area. That hole goes through to an open area of the saw so not at the oil tank or other place that seemed critical. Any suggestions what could cause the oil to turn black?
Another question:
The Stihl oiler has a groove. Is that for an o-ring?