McCulloch Chain Saws

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Sounds like a cutting buddies of mine. They wonder why I have a few heavy, ear-shattering loud old relics but I let the saws do the talking. I like to use the Super 250 and the $30 PM700 for these situations. Now to just get a 660 geardrive and a SP125 to go with them...
Mac 850 ....1 .....36" poplar .....0!!!!!!
 
Hey Eccentric....I'll be putting the 850 to work tomorrow cutting a couple of truck loads of pine. I'll try to get some pics.


Eccentric.....

As promised. I put 18 of these on the ground today, all about this size. Three truck loads, cut, bucked into 33 footers, and down the road. LOL...I told you that 850 wasn't going to be a shelf queen but this is the most work I've put on it so far. It never missed a beat all day...you did a fine job on that saw.
Sorry for the poor audio, the saw sounds much better in person.


http://vid691.photobucket.com/albums/vv277/gologit/P2050287_zpsd6mkk63s.mp4
 
just had a super pro 70 given to me for free . has god compression . I will try to get it going this week end. is this a 70 cc saw?
 
I have an SP70 that wouldn't run when I got it, seemed to have low compression.

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I was able to find a NOS cylinder and piston so it put it back together.

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I was disappointed when I ran it, until I was able to run it side by side with AWOL's mildly worked over CP70; it was faster in the cut than the CP70 no matter who was running it. It just doesn't have the scream you are accustomed to hearing from the 10 Series McCulloch saws.

Oh, I was also comparing it with a really nice PM850 the first time out, guess that was not quite fair.

Mark
 

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Well my super 6-10A doesn't sound of feel near as strong as my 700. But yea, Mark, that 850 is gonna make most stuff seem week. I thought my 800 was strong (and it is), till I saw an 850 run at the last GTG. Man, the Q port seems to rob them of some power. Seems the 800 is good for a 28" and the 850 at least a 32". Got me a 32" 850 now :dancing:.
 
Thanks for the info Mark, it kinda co firmed what i witnessed. I am guessing the 7900 was faster, like my 460 is, however I bet it takes a lot more to stop the chain with any of the 82cc Macs. And my low hour 800 is as smooth as my 372 in the vibe dept.
 
My experience is in aggreement of your assessment Mark. I think that reliable modern style high rpm saws technology was not obviously there in the 70's & 80's but also the trees being logged, at least here on the west coast, were larger so torque to run the longer bars made perfect sense. With a long bar, a Mac of comparible size to the modern saws, is not giving away much and probably will outdo its modern counterparts.
 
got my super pro 70 to run. the decompression valve doesn't seem to release and it is idling way to fast , but should be a fun project for the rest of the weekend, not to bad for a free saw
 
Remove the compression release valve (requires a 7/16" 3/8" drive deep socket), then remove the small socket head cap screw that blocks the opening into the cylinder and remove the accumulated carbon from both ports. I expect you will find the passage into the cylinder is completely blocked.

Make sure you get all of the accumulated carbon cleaned out of the cylinder before you put it back together and start it up again.

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Mark
 
I ran my PM850, PM800, and PM8200 all side by side with my Dolmar 7900 at the WKY GTG last September, the PM850 was the only one that was even close.

The last photo above is Joey running the 850 in the sycamore log we were cutting on. (Edit, that looks like Joey's SP81 perhaps...)

Mark


That was a fun trip to the WKY GTG. I was surprised by that 7900. It made me want one and I even looked around a little. My guess is that if we put a 38" bar on that 7900, it would do pretty much the same as the PM850. I'm running a 38" on my 850 and it does very good. I remember pushing that 7900 pretty hard just to see how much it would take to stall it and I was surprised how stout it was.

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Sent from my iPhone using Tapatalk
 
what would cause my sp70 to idle to high with the idle screw backed right off?


Your throttle link is likely tweaked a bit. They get bent when we remove/reinstall the carb. Try tweaking it a bit. The 'quick and dirty' method is to hold the throttle arm still and pull the trigger a bit. Don't go crazy with that, as you can break the trigger. It's plastic, and the bit where the throttle link attaches isn't very stout. Just a small tweak will likely get things back in line.
 
Hey Eccentric....I'll be putting the 850 to work tomorrow cutting a couple of truck loads of pine. I'll try to get some pics.

Eccentric.....

As promised. I put 18 of these on the ground today, all about this size. Three truck loads, cut, bucked into 33 footers, and down the road. LOL...I told you that 850 wasn't going to be a shelf queen but this is the most work I've put on it so far. It never missed a beat all day...you did a fine job on that saw.
Sorry for the poor audio, the saw sounds much better in person.


http://vid691.photobucket.com/albums/vv277/gologit/P2050287_zpsd6mkk63s.mp4

Thanks for posting that video Bob. I'm very happy to see that you've put that saw to work, and that it's doing well for you. I haven't had much luck capturing the real sound of a saw with video recordings either. Makes my day to see an old Mac being put to work again like that.

From what I was able to hear, you can probably lean it a scosh for a bit more power. Those rings are probably broken in by now. As long is it's 4-stroking at WOT unloaded, cleans up under load, and drops back to 4-stroking when you lift cutting load it's fine. I don't like to run 'em on the ragged edge (and I know you don't either).

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Well my super 6-10A doesn't sound of feel near as strong as my 700. But yea, Mark, that 850 is gonna make most stuff seem week. I thought my 800 was strong (and it is), till I saw an 850 run at the last GTG. Man, the Q port seems to rob them of some power. Seems the 800 is good for a 28" and the 850 at least a 32". Got me a 32" 850 now :dancing:.

I agree with you guys about the PM850 vs the PM805 and later versions. The 850 (and late SP-81) seems to be the strongest of the lot. We were pondering this subject at the GTG last year. Your 800 is certainly a healthy saw in great condition, but Bob's 850 just seemed to have more beans.

Here we're making sure Bob's saw is 100% ready to go before he received it later in the year. After these shots were taken, I installed a better clutch cover (from a buncha 10-series stuff give to me by Farley9N Bob at his GTG). Also installed a nicer AF cover from Warped5 Ted.

If we're fortunate enough for plans to come together, maybe Mark can bring a few of the later 82cc saws to run.

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Aaron, I am sure we all would love to see Mark and any saws he brings. I will bring that 800 and my 850, and Big Mike has an 800 that runs great but smokes I will try to get him to bring it. We repaced the seal/gasket and it still smoked, pulled the piston and it still had machine marks in the cylinder. So maybe we can get it straightened out.
 

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