I did a little write up on the valve repair that may be helpful.
There is also an oil tank vent hole behind behind the discharge hole in the bar pad. Some of mine have a piece of wire that fits the hole loosely to plug most of but not all of the hole. This is to minimize oiling when the saw is shut off to relieve pressure in the oil tank. If this wire is missing, it won't build enough pressure in the tank.
I have heard that not all of the saws had the wire and likely have a smaller diameter hole.
In case some of you don't visit the baconville site I thought I would share this with you.
I suspect some of you may have Poulan Micro's with the oiler check valve which is located behind the clutch. They give up after some period of time as they have a duckbill check valve which dissolves and won't oil.
This will let you know how to renew the valve which is becoming difficult to find.
There is a duckbill and a brass bushing inside. I searched some time ago and someone had repaired them successfully.
The one I took apart looks like this. The screen is missing.
The duckbill goes in flange up followed by the bushing which is stopped by a shoulder in the body and then the screen which is MIA
I cleaned and reassembled the valve parts in the order in the above pic. The duckbill is Poulan PN 530026119 which is readily available.
As mentioned previously, I had filed the top off that valve to remove the screen so I had no room to put the screen back in. I'm not sure how much debris the screen keeps out as the three I have removed had clean screens. I guess I will see if I use the saw for some length of time.
A few notes.
When the bushing, which is a slight press fit goes in, make sure it is
firmly seated against the duckbill. If it is not, air will leak back to the crankcase and no pressure will build in the oil tank.
I peened the bushing / valve body to keep the bushing in place.
If I do another I'll pop the rolled lip back with a shaped drift so I can put the screen back in.*
Some other member(s) mentioned that they used some JB Weld to put the screen back on but I was a little reluctant as I wouldn't want it to fall off and end up in a bearing.
If you haven't run one of these before make sure you release the pressure in the oil tank by unscrewing the cap or it will keep oiling after you shut it off until the tank pressure bleeds off.
*I have run the saw several times and really don't find any reason the replace the screen. All is still very clean.
It works great.
They are very snappy little saws and nice to use.