McCulloch Chain Saws

[HavinFun]

Mac 850 question. I was showing someone a picture of something on my phone and he saw a picture of my newly acquired yellow Mac. He asks me if I’m into Macs, and I said I really liked them. He then says he has two 850s, one runs good, other doesn’t but has good compression. Says he’d like $1k for both. I don’t need them, but thought they might keep me going on the collection. So, is that a fair price? Thanks.

 

[heimannm]

Welcome McS55A. Your saw appears to have an H&S spike, a very nice addition. Personally I don't like painting a saw that has character, I've only had a paint two or three that were just too far gone to ignore. In all likelihood I will have to paint one or two of the 2 man saws I have awaiting attention since 90%+ of the original paint is gone or flaking off.

On your saw, the crankcase and the gear case (filled with gear oil) are only separated by a seal, if that seal is leaking it could be allowing oil from the gear case into the crankcase which would certainly lead to a lot of blue smoke.

Your saw is also equipped with an air vane governor, try forcing the throttle open at the carburetor (not with the throttle trigger) to see if that makes any difference. It is possible that the governor is closing the throttle when you are trying to run at high speeds.

I have a 55 (72cc version of the same saw) that runs very well.



Mark

 

[heimannm]

A really nice PM850 in good running condition with a desirable bar could easily be worth $500, a non runner is a big question mark to me.

Mark

 

[Joe Crocco]

I agree with vinnywv fix and use.

 

[MacSuper55a]

Welcome McS55A. Your saw appears to have an H&S spike, a very nice addition. Personally I don't like painting a saw that has character, I've only had a paint two or three that were just too far gone to ignore. In all likelihood I will have to paint one or two of the 2 man saws I have awaiting attention since 90%+ of the original paint is gone or flaking off.

On your saw, the crankcase and the gear case (filled with gear oil) are only separated by a seal, if that seal is leaking it could be allowing oil from the gear case into the crankcase which would certainly lead to a lot of blue smoke.

Your saw is also equipped with an air vane governor, try forcing the throttle open at the carburetor (not with the throttle trigger) to see if that makes any difference. It is possible that the governor is closing the throttle when you are trying to run at high speeds.

I have a 55 (72cc version of the same saw) that runs very well.

View attachment 1176670

Mark

Thanks for the suggestions. I think I have tried bypassing the governor before, but I will definitely try again. For the gear case seal, it there a definitive test I can do to see if it is in fact the gear case leaking? Could I pressurize the gear case and spray soapy water and look for bubbles?

Thanks again,
Andrew

 

[heimannm]

The leak may be occurring between the crankcase and the gear case. A better test would be to block off the intake and exhaust and try to pressure and vacuum test the crankcase to see if it is holding.

Mark