McCulloch Chain Saws

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That I can not answer. Maybe someone else here can. I know more fuel is a great thing, right up until its to much lol
Yeah, that's kind of what I was wondering. Of course, if it's not too much fuel for a 100cc Pioneer it probably shouldn't be too much for a 123cc Mac. Hmm, once I get my saw and my buddy's saw running I may throw a 53 on mine and run them against each other.
 
Maybe this will help:

According to the McCulloch carburetor book, the SDC18, SDC19, and SDC20, and SDC22 are all .750" venturi and .812"throttle bore.

The HL19 and HL63 have a .687" venturi and .812" throttle bore.

The HS 70 and 71 have a .687" venturi and .812" throttle bore.

Funny thing is the SDC18 was original equipment on smaller saws (CP55/70/7-10 and Super 2-10 & Super 6-10), the HS71 was used on several of the smaller saws as well.

The SDC19 was used on some 795L and Super 797 saws.

The SDC20 & HS70 were used on the CP125

The SDC22 was used on the Super 2-10C

I swapped the original fixed jet SDC on one of my SP125's for a fully adjustable SDC18 (after modifying it to accept the remote impulse line) and the difference is definitely noticeable.

Mark
Ron
 
As for the 1-10,I had to put it on the shelf again.I got the carb on with the throttle & choke rods & cut down on the lengthy of the bolts for the throttle tank by about 3/16 in.I went to instyall the fuel line that was on the bullfrog carb,but it wouldn't stay on the inlet nipple.I tried another fuel line that's more "common" to the Mac saws,but it just fell through the hole in the fuel tank even after wrapping it about 6 or 7 times with Teflon tape.It seems that Mac used 2 different size fuel lines back in the day,one was slim,the other was a bit fatter.Mark,the fuel lines you have that I used on the PM850 may possibly work here,part # 63935.I know it fit quite snugly into the 850 tank after I reamed the hole a bit.My only other alternative is to use a grommet with a Tygon fuel line & put a spring in the fuel line so it doesn't kink.I have 2 other non-Mac saws to repair,then I'll come back to the 1-10.I'm also trying to get my basement filled with wood for the heating season before I go on the cutting table on 9/20.
 
Yeah, that's kind of what I was wondering. Of course, if it's not too much fuel for a 100cc Pioneer it probably shouldn't be too much for a 123cc Mac. Hmm, once I get my saw and my buddy's saw running I may throw a 53 on mine and run them against each other.
I've seen huge carbs adapted to the 125s ,( think 088 carb or model air plane) . I don't think you can go too big with any factory carb McCulloch offered.
Homelites had some sizable SDC carbs on their later 6 cube saws also.
 
I took a fixed jet tillotson once off a 125 (hs124a) and a tillotson hs111a from a sp80, swapped all the parts around to make a fully adjustable carb for the 125 saws. Worked great. The tilly carb for the 125 saws thats fully adjustable is the HS70A., the walbro is a sdc20.

My pm55 is wearing a pioneer sdc carb. Walbro sdc 53B.
 
The DE80 used an SDC85 if I'm not mistaken.I also picked up a pair of SDC65s back a couple of months ago.I don't have the specs on any of them,but the 85 runs the DE80 just fine.I picked up the 65s for the way the adjustment screws are positioned on them for putting them in 10-10s & possibly 2-10s.
 
The DE80 used an SDC85 if I'm not mistaken.I also picked up a pair of SDC65s back a couple of months ago.I don't have the specs on any of them,but the 85 runs the DE80 just fine.I picked up the 65s for the way the adjustment screws are positioned on them for putting them in 10-10s & possibly 2-10s.
That is correct, I just know the SDC 80 is a highly sought after 6-cube Pioneer carb and I'm curious if the performance factor that endears it to Pioneer guys will apply to the CP125 engine.
 
No. Its for a points ignition coil. That cylinder can use either coil. If its a points coil there needs to be a small barrel spacer to fit there of some sort. When the replacement cylinder was purchased it came with the spacer. Its just a small aluminum barrel. Anything that fits would work though. Several little washers stacked for example. As long as its the right height and has a hole for the bolt itll work.
 
Special Pre-Season North East Tennessee MAC Report

Last Wednesday night a little PM800 action.

A nice white oak.
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What can happen when you stall in the cut. Small hickory.
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There are situations where I really appreciate a long bar. Managed to slowly lower the chair from a relatively safe distance should it have broken.
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By Thursday evening my arms were covered in a rash from the sumac vines on the white oak. A small price to pay for time in the woods.


Today PM800s and 1010S

It was a beautiful day today mild temperatures with the occasional breeze in North East Tennessee. Blind Squirrel Falling had a light schedule – limb, buck and skid the hickory and fall a large white oak. If Blind Squirrel had more help, even just one more, a name change would be in order. I am thinking something along the lines of Three Stooges Logging.

We used Brian’s PM800 and 1010S on the hickory. I told him one day his 1010S was going to go missing. Unfortunately, he knows where to look. I really enjoy that saw. Its short bar always takes an operator adjustment for me, but it is a sweet saw. The hickory went well enough that we added another oak to the schedule. I don’t have any pictures of it.

Brian wasn’t feeling well so he decided to call it a day. I pointed out that I didn’t want to tackle the large white oak without someone there to watch my back. As always, Brian stepped up and indicated that he was up for one more. Anyway, we took on the tree below and cut it about 4' high in keeping with the LO’s minimum 3’ stump requirement. The plan was to leave the smaller tree as its natural falling path would be into the street. Using my PM800, I cleaved the two trees apart. Made a narrow bore cut and then I made the face cut. Satisfied that everything looked good, I reinserted the bar and began to finish the back cut. I kept at the cut as the fall began to prevent a barber chair. Unfortunately, the fall stalled. With a little head scratching and investigation, we discovered what appeared to be grafting of two limbs on the trees near the top. We tried to wedge it over but made small progress. We tried to get a line in the tree but with my lack of athleticism and Brian’s bad shoulders, we couldn’t. My 1 ½” wrench was too heavy for me to reach the necessary limb and two 8” crescent wrenches were too light to pull the line down. We debated thinning the hinge further, but it was so thin that I was already regretting chasing the cut. After a lot more head scratching, Brian half jokingly offers up why we don’t try to pull it down with the vines. What the heck why not, things can’t get any worst, and we can’t leave things as they are. So Brian cut loose three vines. We wrapped them together securely with a short tow strap, hooked the strap to a cable that ran through an anchored snatch block and then hook the cable end to the dozer. With some skepticism, I slowly reeled the winch in and eventually the tree came down smashing everything in its new found path. We decided to leave the bucking to others, or at least for another day.

If you look close, you can see the grafted limb about 1/5 down the picture on the smaller tree.
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The stem was 29" at the cut and is 22" forty feet out. Pretty heavy. It fell in the direction of the pull. We didn't have an anchor point in line with the planned falling path.
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Be safe,

Ron
 
A few more pictures from today.
The last tree we fell:
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Ron standing by the tree that gave us such a hard time.
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The tree after fell:

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The stump. I am so short that I almost had to stand on a ladder to take this picture.

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The mighty crawler. Has saved us so much work.

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The tree that gave us so much fits!!!

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Where the two trees were grown together and we did not see until Ron had already had it cut and unstable.

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Ron's saw in the cut.

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Again Ron's saw in the cut.

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A nice plum of sawdust from a good sharp chain. Ron's saw.

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Ron Cutting big timber.

Contused on next post
Brian
 
More pictures from todays cut.

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Face Cut

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Ron's PM800

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Separating the trees at the bottom.

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The crawler is closer to me than it looks. I don't let just anyone drive up this close to me. He wound up almost against me by the time he was in position to pick up the log. I must have a lot of trust in Ron.

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Ron on his mighty crawler. This thing will pull more than you would think.

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Ron with my PM10-10S semi stuck, but he got it loose without help. Now me, I got two saws stuck and required Ron's assistance getting them unstuck.

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Ron cutting with my PM10-10S. I have got to watch him from now on. He made the commit that if I turned my back that saw might land itself in the back of his truck.

Continued
Brian
 

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