McCulloch Chain Saws

[2broke2ride]

Please excuse the shaky video my 9 year old took. Can you guys critique my tune and tell me from this if the saw seems to be running as it should? It seems to four stroke nicely and clean right up in the cut but I'm not super familiar with these oldies.

 

[fossil]

Please excuse the shaky video my 9 year old took. Can you guys critique my tune and tell me from this if the saw seems to be running as it should? It seems to four stroke nicely and clean right up in the cut but I'm not super familiar with these oldies.

Sounds like it's well tuned. Might be a little down on power. Mark could comment on that better. I don't think many saws from the early '60's are too quick.

 

[2broke2ride]

I was thinking that, might shoulda slapped a set of rings in it when I had it all apart. Oh well, it starts and runs well, I'm gonna use it as is for now. Not like it's gonna be my primary saw.

P.S. Mark contributed the stack muffler to this saw[emoji106]

 

[fossil]

No wonder it was so quiet!

Your son did a great job on the camera.

I have an old PM Canadien badged as a Skil from that era. Runs great but pretty slow by 70's and forward standards. A collector with a bunch of them said mine would run with his.
I also have a nice 380 which I never got running

 

[2broke2ride]

So I pulled a compression test on the saw, showing 120 on my gauge.... Good as far as I'm concerned. Only problem is the plug was very gray when I pulled it out, like aluminum kinda gray so now I'm nervous. I don't want to melt it down. I am running the same 32:1 premix I run in all my saws and weed eaters.
I thought I had a pretty good handle on tuning a saw but this oldie has me second guessing. I could really use some help. I messed with it some more tonight and I am confident that I have a solid fourstroke with no load, it idles well, has good throttle response and clears up in the cut. Problem is it still seems down on power. Please help!

 

[leecopland]

If it seems down on power you are probably safe as far as too lean goes. Saws seem more powerful when lean, to me anyway.

 

[2broke2ride]

If it seems down on power you are probably safe as far as too lean goes. Saws seem more powerful when lean, to me anyway.

I agree, but how do we explain the gray plug?

 

[fossil]

Spark plug manufacturers generally agree that the proper color on the insulator should be tan or grey.

The plug spec'd for the saw is a Champion J8J which is a pretty hot plug.

Do a few more cuts to get the saw hot and kill the engine at wide open throttle. Post a pick of that plug.

 

[2broke2ride]

Ok, will do tonight

 

[2broke2ride]

Plug pics

Of course now it's running like crap again[emoji853]
I don't get this saw.
I bought a new plug, gonna try it.

 

[fossil]

I have never seen anything like that before.

If you don't here anything on the Mac thread, post your pics over in the main chainsaw forum.

Start a thread
...somewhere else as well.

 

[2broke2ride]

It's almost like ash buildup on the insulator........

 

[fossil]

Did you try the new plug yet?

Any chance that build up is in the exhaust port as well?

 

[leecopland]

Maybe using outboard or motor oil?

 

[2broke2ride]

Maybe using outboard or motor oil?

I was using outboard oil because I was out of my normal oil, maybe that's all it was.
I have since switched back. The gray is like an ash that I am scrape off with my fingernail and it's nice and tan underneath it. Haven't checked the new plug since I installed it.

 

[2broke2ride]

Gonna ask again about tuning this saw. Can I just shoot for max rpm in a cut? I have played with it quite a bit and if this is the way to do it I have it tuned a bit to rich. If I tune for max rpm I don't seem to get a noticeable fourstroke unloaded.
I really want to get this saw running as well as possible and I don't want to burn it down.

 

[heimannm]

It should four stroke when you lift it in the cut, clean up when you put a load on it.

Mark

 

[2broke2ride]

It should four stroke when you lift it in the cut, clean up when you put a load on it.

Mark

Mark,
This is my problem. I tune all of my saws that way and they run fine, this saw seems way down on power if I tune it that way.
If I tune for good power in the cut I don't notice the four stroke when I lift.
That's why I'm not sure what to do.
Both ways leave me richer that factory setting but it takes almost a full turn on the screw for me to notice it fourstroke.

 

[heimannm]

A few of the bigger McCulloch saws that I have needed to be much richer than you expect to get enough fuel in the cut. I don't know if they just had some carburetor issues (stiff diaphragms, metering lever too low, etc.) or if they really needed that much more fuel.

Mark

 

[briantutt]

that might be what the PM650 needs. it has less power than it should yet it 4 strokes when out of the cut.

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