# McCulloch Chain Saw



## ggb715 (Aug 28, 2008)

I have a McCulloch Power Mac 310, model # 600042H, Serial # 16-024011, Factory # 1016604200-08,bought on Sept. 12, 1984

I have replaced the carburetor and starter drum. It has good spark. If I take the spark plug out,the engine turns over very easy. When the plug is in I can not turn the engine over at all or it is too hard to get it started. My ? is what is causing this.


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## Maytag (Dec 10, 2007)

plugged exhaust port?


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## ggb715 (Aug 28, 2008)

Thanks, will try that and get back.


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## ggb715 (Aug 28, 2008)

Took the muffler off, no obstruction, took plug out , engine turns over very easy, screw the plug in a couple of turns and you can't turn the engine over.


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## duffer72 (Jul 23, 2011)

Wrong plug in it hitting top of piston??


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## ggb715 (Aug 28, 2008)

The plug that I'm using is a NGK- BM6F this is one of the plugs that the manual calls for. The other plug is a Champion DJ8J remember that I said I only screwed the plug in a couple of threads not all the way and it still would not turn over normally


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## usmcgrunt (Sep 16, 2007)

Hello.Do you have the chain brake off or engaged when trying to start the saw?If the clutch is sticking,it would be very hard to overcome the engine compression and a brake holding the sticking clutch.I had a model 320 and from what I can remember,it ran great but was pretty hard to pull start,hot or cold.The handle wasn't long enough to put a foot on it and pull.


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## ggb715 (Aug 28, 2008)

It's very hard to pull with the chain on or off. Right not I have the chain and the muffler off so that I can see the piston. With the plug out , it pulls easy, with the plug screwed in just a couple of threads it pulls hard, with the plug all the way in I can hardly pull it at all.


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## Spit (Nov 3, 2006)

Does anyone know if this saw has some type of compression release that may not be working?

Spit


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## Rentahusband (Aug 25, 2008)

Has it been sitting for awhile?


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## ggb715 (Aug 28, 2008)

Yes the saw has been setting for awhile.


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## ggb715 (Aug 28, 2008)

The saw is in excellant shape, I hate to give up on this.


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## Rentahusband (Aug 25, 2008)

Have you actually looked at the clutch to see if anything may be rusted due to it sitting for awhile? Have you tried turning it over without the bar and chain on?


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## Maytag (Dec 10, 2007)

Sounds like its hydro-locked if I'm using the term correctly. It's when fuel or oil is in the wrong spots and it doesn't allow air (or gaseous fumes) to move into places they normally should. Not sure how that would happen on a 2 stroke. It's the same reason they "walk" the propeller around on old planes before starting if I'm not mistaken. It's so the excessively high compression caused by liquid leaking into the cylinder doesn't blow a cylinder on startup.


FYI - I'm not an engine mechanic. Just offering some thoughts. Hopefully the "big guns" will be able to respond soon and get it solved for you.


>Maytag
> maybe crankcase breather/reeds are plugged. That is if there is a breather on 2 stroke. I believe they may or may not have reeds depending on design but not sure on breather.:freak:


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## ggb715 (Aug 28, 2008)

I have tried to turn it over without the chain and bar and get the same results. I thinking of to much gas or oil in the cyl, but how is that happening.


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## Rentahusband (Aug 25, 2008)

Try loosening the carb and see if it turns over easier. This would eliminate the possibility of to much fuel. Mabey the sitting has done something internally. Wish I could look at it for you, as I am puzzled without having it in front of me.


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## ggb715 (Aug 28, 2008)

Thanks, that was my second thought.


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## ggb715 (Aug 28, 2008)

Took the carb off and still is hard turning over.


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## Spit (Nov 3, 2006)

Are you starting the saw with it flat on the ground, holding it down with your foot through the handle, one hand on the top handle other hand on the pull rope handle? If not try it that way and see if you can't get it to start.
Spit


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## compass.1 (May 14, 2012)

*flywheel key?*

Have you checked the flywheel key? A damaged flywheel key can sometimes cause compression problems.


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