Chainsaw Repair

Quote from: hotshot on December 10, 2013, 03:22:07 am

First post here, but the small steel cam gets driven from the shaft by the
"crush" when you tighten the clutch assembly down against the cam, or in
other words it is stacked in there like a washer being pressed against the
crankshaft journal. 

What a great engineering design, with the brass gear reducer cammed in a
roughly a 19 to 1 ratio.  There are 19 teeth on the brass driver, and 20
teeth in the stator. Note that one of the gear tooth pockets on the outer
gear is always empty. The face of the brass driver gear has a short cam
cast into it too, that the cross piece button rides on.

One turn is made to stroke the plunger for every 19 rotations of the engine, or
about 5 short plunger strokes per second at 6000 RPM.  Looks like the designer
must have played with his kids Spirograph drawing set back in the 70's, if you
remember those.

Anyway, you probably have a quad ring rubber seal that is simply worn
out, it goes around the plunger pin that is actuated by the cross shaped
piece that is driven by the face of the brass gear.  You have to dig it out of
the bore with a dental pick, at least most of the time you do.

Hello, and welcome hotshot...I don't suppose you know anything about the oilers on the PP295, 4620AVL's  do you?  I own a 295 that runs/oils great, and I bought a 4620 that runs great, but does not oil to save it's "you know what" anyway, just looking for some more insight (I've replaced the oil pump with no luck), thanks, John.

I believe once you remove the oiler on those that there is a small rubber tube that runs into the oil tank.   You can just pull it out and make sure it is not plugged up.   The only other thing to look at is the worm gear and make sure it is engaging the oil pump correctly.