Chainsaw Repair

Two-Stroke Basics Visible Training Aid

I had to learn how a two-stoke engine worked when I started working on chainsaws.  Went to the library and spent some time looking at books - took me a while to 'get it'.  More information is available on the web now.  But here is a simple training aid I made, for use in introductory chainsaw classes I sometimes teach, after seeing one posted on another site.

This is the cylinder from a cheap, garage sale, Homelite clamshell saw, cut in half to show the intake and exhaust ports, bearings, counter weight, transfer, etc.  I also have the clutch and flywheel I can add on.  Very easy to do with a hacksaw, vise, and a little patience.  Even easier if you have access to a metal-cutting bandsaw and belt sander.  I flattened the sides with 80 grit, then 120 grit sandpaper, then hit it with a ScotchBrite polishing wheel to smooth the surface, and eliminate sharp edges.

I added a handle to make it move.  Compression is a little low - might have an air leak somewhere?

Philbert

There are several Two Stroke animation videos on You Tube, that help illustrate how these engines work.
This one is pretty basic, but clear:

https://www.youtube.com/watch?v=xNLE8G3pC0k

Philbert

Very Nice.   When I first started learning 2 stroke engines I got most of my information from the net. 

Very nice!  Mine has been a most invaluable tool to understand how 2-strokes work.  For me anyway it is harder to get the same feel from a video or diagram - I can work that way but it's harder.