You stated "after being in a shop". What was it in the shop for??? What problems/symptoms ETC?
Can you turn the flywheel by hand easy or is it hard to turn? If it turns easy check and clean your recoil starter by taking it apart.
Crank bearings are probably half froze up and need replaced. Also check for dirt and debris on clutch side around the clutch and sprocket also.
There are a few things that could cause this, one is a large buildup of carbon on top of the piston and the combustion chamber,
but if you swapped the piston, it is assumed that you decarboned things.
Another possibility is that the oiler is letting bar oil into the crankcase.
Another, is that the carb is flooding a tad.
Found a really good website that sells parts online. decently priced too. www.partsareparts.com
Yeah, I don't think you gave us a model number, so I don't have a clue what oiler setup you have just a guess going by the age and description. Most of those used a little diaphragm oiler that was pumped by the impulse of the crankcase, and if the diaphragm would crack, it would let bar oil suck into the crankcase and eventually into the combustion chamber.
the same scenario would occur if the carb was flooding, it would "hydro-lock", as the engine cannot compress a fluid.
to find out drain both the gas and oil tanks and thoroughly rinse with fuel mix. Drain for a day or two upside down, filler plugs and spark plug out/off/gone, and periodically pull the rope a bunch of times to thoroughly dry it out, do not have the plug
attached to the plug wire, or you could have a green flamethrower. After you are convinced that the system is totally dry,
reinstall the plug and pull it like you were going to start, with no gas or oil in it, and see if it pulls a lot better.
If it does, then add fuel mix only to the gas tank and try to start, off course leave the bar and chain off.
Found a really good website that sells parts online. decently priced too. www.partsareparts.com
Yeah, I don't think you gave us a model number, so I don't have a clue what oiler setup you have just a guess going by the age and description. Most of those used a little diaphragm oiler that was pumped by the impulse of the crankcase, and if the diaphragm would crack, it would let bar oil suck into the crankcase and eventually into the combustion chamber.
the same scenario would occur if the carb was flooding, it would "hydro-lock", as the engine cannot compress a fluid.
to find out drain both the gas and oil tanks and thoroughly rinse with fuel mix. Drain for a day or two upside down, filler plugs and spark plug out/off/gone, and periodically pull the rope a bunch of times to thoroughly dry it out, do not have the plug
attached to the plug wire, or you could have a green flamethrower. After you are convinced that the system is totally dry,
reinstall the plug and pull it like you were going to start, with no gas or oil in it, and see if it pulls a lot better.
If it does, then add fuel mix only to the gas tank and try to start, off course leave the bar and chain off.
Crank bearings are probably half froze up and need replaced. Also check for dirt and debris on clutch side around the clutch and sprocket also.