Chainsaw Repair

Well the 3.7 arrived today   The saw has  definitely been through some wood in it's days but there's absolutely no signs of piston(2 thin ring,C/B  or bore wear or scoring but will need re-ringing as the compression limit was 110. The power head definitely feels better and lighter than the 5020 I have. Gonna get it cleaned up,parts ordered and search this form for the finer details of rebuilding and modding .

Dry, the craftsman 3.7 with b/c 14.8,5020 with b/c 15.6,that's with my scale.

Your 5020 dry with 20" b+c is about right.  Full of  fuel, oil, 20" b c 16lbs 8oz

I was looking at the part numbers for the 3450/3750 and they do not share the same number for the 3000
So I would say the crankcases are different.   How they are different I do not know.

Muffler is smaller on 2800-3300 crankcase is wider on starter side front.  3450-3750, etc muffler is wider than 2800-3300.  Crankcase muffler opening is (starter side front) wider for larger muffler.  Clutch side of crankcase appears to be the same on all models. Starter side is diff. on 2800-3300 than 3450-3750,etc.
Shep