McCulloch 10-10A starting problems

[Oldmechanic]

I have a Mac 10-10A that I bought in 1975. It has served me very well over the years. But this week I had a tree blow down and needed to cut it up. My old saw has not been used in about 4 years. Before I put it up, I drained the gas and oil, ran the carb empty and put a little oil in the cylinder. When I tried to crank it, it is VERY hard to pull the rope. Feels almost like it is ratcheting and when it kicks back sometimes it jerks the rope out of your hand. I opened it up and checked the exhaust for blockage, checked the muffler and lubricated everything that moves. With the spark plug removed, it is so easy to pull that I can pull it through with two fingers. But when the plug is put back in, it is so hard to pull that it is almost impossible. Sometimes when pulling really hard it will emit a small puff of smoke from the muffler, so it is trying to light off. Any ideas? I really don't like the idea of getting rid of the old saw, but I am out of ideas.
Thanks for your advice and help.

 

[Bob Hedgecutter]

Oil has an amazing ability to up compression, oil in the carb pulled through to the combustion chamber will weaken any fuel making it in there. A saw stored dry for a number of years might take some pulling to get fresh fuel all the way through the works.

I would at the very least strip the filter cover, air filter off the saw- pull the plug- rinse the cylinder and crankcase out with fresh fuel mix to lube the bearings and wash out any residuals- with plug out, tip the saw upside down and wash out the rinse fuel- put a new dry plug in check for spark and then prime the carb down the throat with a little premix- try to fire it off.

 

[Oldmechanic]

Thanks. I'll give that a try tomorrow and let you know how it works out.