Rebuilding a vintage Poulan K100-Compression Test

[Poulan K100]

I've had this saw for the last seven years and always wanted to restore it. I recently finished my basement shop so it's time to get started.

The saw, a K100, is a 4.18 cu in solid cast aluminum and I would love to see it run and cut wood again but I need the masters (that'd be you guys) to help me through the process. I need to see if it's worth saving first.

Cosmetically, the saw is in great shape and is all there. I did a compression test on it cold, turning the fly wheel by hand, and came up with 30psi. This seems discouraging but wanted to qualify the statement by saying that I did the test by hand (slowly) and used an automotive compression tester. Is there another kind designed for saw type engines? I opened the choke and throttle as the instructions recommended. Is this correct?

I could probably get the saw started by changing fluids to do a hot test but wanted to check with you guys to see if its worth it after the cold test.

Finally, if the cylinder needs to be bored (which could be great because it's that much more power) how likely is it that I'll find another piston to match this one with the extra .10 over bore? Since I don't see any posts about locating pistons, I assume a modern piston from another make or brand will interchange with mine.

Thanks for the commentary.

Scott

 

[Butch(OH)]

You cant test compression turning over slowly by hand. Briskly pull starter rope as you would to start it. Also a dry engine will not build real good comression and yours is dry after sitting that long. Squirt some oil in the cylinder throuh the plug hole and slowly pull it over, be sure to use enough so it can lube the entire cylinder. Then pull briskly to expell excess oil out the plug hole. Screw the plug in finger tight and try it, youll then know if it's OK without even using a gauge. It takes some umph to pull over a K100, Id say about the same as my 60CC modern saws. Mine runs like a champ but Im looking for a chain I can offord since the racers run all the 1/2' up to the moon. Thinig seriously about converting it to .404.

 

[Butch(OH)]

I just noticed you are in Marysville, I'm about 45 minutes away in M Vernon. When you get it going bring it over and we will do some K100 racen, lol

 

[Butch(OH)]

Heres a picture of mine, ready for racen.

 

[Poulan K100]

Poulan K100-Compression Test

Thanks, Butch. I followed your guides and added oil and reattached the recoil to try again. I probably wasn't clear enough in my initial post to say that I was turning the fly wheel by hand instead of using the recoil. Anyways, the compression test yielded a 140psi reading the first time around and 150psi the second which is great. I cleaned up the saw and downloaded some information regarding the saw and carb. Here they are if you haven't found them already.

Carb info, pictures, and diagrams:
http://64.180.101.188/cscc.nsf/e723...4df98b7afada68cc88256e0f0079e928?OpenDocument

K100 details:
http://64.180.101.188/cscc.nsf/ed1d...b63c0003dd85f24288256b340080104b?OpenDocument


Was great to see that they still make parts for the carb anyway. I'm going to order the rebuild kit. Do you remember what your kit consisted of? Just Gaskets and diaphragms OR does it contain needles and seats too?

Do instructions come with the kit to tell you what to set the high and needles to?

Thanks,
Scott