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I just did something pretty cool that i have to share for everyone. I made a fully adjustable carb for a 125. It started while watching "Bellhopper" on youtube. He has been working on his sp125 for awhile. It had a fixed high jet carb on it. He took a sdc off a 10-10 and made it work very well.
It got me thinking....i have a cp125 with a fixed high jet carb. Its a tillotson HS124A. I knew i also had a spare from an pm850, also a tillotson, HS111A. Plus a rebuild kit, so i was off to make this work.....first i checked the carb specs and they have the same size venturi. Check! Next i bundled up and went to the garage to get started. Took the 111a and then got the 124a off the cp125 and set them beside each other. Everything was gonna work great. I had to use both carbs to piece together one carb. I took the choke clear out and swapped them. Did the same to the throttle butterfly and rod. With those swapped the choke linkage and throttle linkages will fit perfectly with no modification. Then i exchanged the fuel inlet barbs. No big deal there. Next was the high and low jets. I had to cut them way down on the 111a to fit properly, more than half got cut off. then add a slot to adjust as needed. Hacksaw for that. I then put in the rebuild kit and looked it over, looks gooood, awe crap.....idle speed screw!!!! The 111a is adjustable from outside the airbox with a separate screw. The 124a is not. So i needed to add the idle screw from the 124a to the 111a carb body. They shared the same tab but it needed drilled and tapped. Very small and careful drilling of that hole. Now a tap. Very small as well. Like a #2 screw. I had one!!!! Slow and steady i got it done. Last was the moment of truth. Will it fit up and work like i am hoping? It fit and was reachable with a screwdriver for adjustments. So, what would i do at 11pm?? Yes, i fired it right up. Took about five pulls but holy cow batman!! It worked perfectly!! Idled way better than before, had crazy response, and fully adjustable top end. I was very happy to say the least. I wont be able to try it out in a log till next week but boy what a difference that made. Sorry this was so long. If anyone would like more specifics please pm me. Ill get you better details and pictures. Vinny
 
I just did something pretty cool that i have to share for everyone. I made a fully adjustable carb for a 125. It started while watching "Bellhopper" on youtube. He has been working on his sp125 for awhile. It had a fixed high jet carb on it. He took a sdc off a 10-10 and made it work very well.
It got me thinking....i have a cp125 with a fixed high jet carb. Its a tillotson HS124A. I knew i also had a spare from an pm850, also a tillotson, HS111A. Plus a rebuild kit, so i was off to make this work.....first i checked the carb specs and they have the same size venturi. Check! Next i bundled up and went to the garage to get started. Took the 111a and then got the 124a off the cp125 and set them beside each other. Everything was gonna work great. I had to use both carbs to piece together one carb. I took the choke clear out and swapped them. Did the same to the throttle butterfly and rod. With those swapped the choke linkage and throttle linkages will fit perfectly with no modification. Then i exchanged the fuel inlet barbs. No big deal there. Next was the high and low jets. I had to cut them way down on the 111a to fit properly, more than half got cut off. then add a slot to adjust as needed. Hacksaw for that. I then put in the rebuild kit and looked it over, looks gooood, awe crap.....idle speed screw!!!! The 111a is adjustable from outside the airbox with a separate screw. The 124a is not. So i needed to add the idle screw from the 124a to the 111a carb body. They shared the same tab but it needed drilled and tapped. Very small and careful drilling of that hole. Now a tap. Very small as well. Like a #2 screw. I had one!!!! Slow and steady i got it done. Last was the moment of truth. Will it fit up and work like i am hoping? It fit and was reachable with a screwdriver for adjustments. So, what would i do at 11pm?? Yes, i fired it right up. Took about five pulls but holy cow batman!! It worked perfectly!! Idled way better than before, had crazy response, and fully adjustable top end. I was very happy to say the least. I wont be able to try it out in a log till next week but boy what a difference that made. Sorry this was so long. If anyone would like more specifics please pm me. Ill get you better details and pictures. Vinny

Awesome Vinny love reading about stuff like that.
 
I think Mark mentioned that MAC switched to aluminum of many of their castings at some point. It's cheaper than Mag but it s 33% heavier which may explain the weight diff between a 7-10 and a 700. It may also explain why the 800, 805, 8200.... and McCinder blocks are so heavy.

I don't know what the PM850 weighs and if it's lighter by some than the later 82 cc versions. I know my 80 or 81 is a few pound lighter than the 800 series.

Question,

Is there any way to tell the difference between an SP80 and SP81?

I have one with no tag with an SP80 winter cover on it but I can see a divider in the transfers on the FW side through the plug hole.

Did a little ummm test on my saws after reading about the mag vs alloy thing again soo don't laugh tooo hard but anyway put a 7-10 and a 700 on the ground now flick the handle and listen to the different ting from the metal the pm saws kind of "ring" and the older ones are more a tat tat like plastic orr composite kind of noise. Go try it if ya don't believe me haha
 
Did a little ummm test on my saws after reading about the mag vs alloy thing again soo don't laugh tooo hard but anyway put a 7-10 and a 700 on the ground now flick the handle and listen to the different ting from the metal the pm saws kind of "ring" and the older ones are more a tat tat like plastic orr composite kind of noise. Go try it if ya don't believe me haha

Put a few drops of vinegar on a clean bare spot. If it reacts, it is magnesium, If it doesn't, it is aluminum. Or so I am told. Ron
 
NorthEast Tennessee Saturday MAC Report

Not so beautiful day in North East Tennessee today. Low forties and misting. Brian had a rough week and took advantage of the weather by staying home. They had called for rain all day and I didn't prepare ahead so I had a slow start. Sharpened a chain for the 800 only to find the chain adjuster pin sheared. Been several seasons since I sheared the last one. Anyway no spare in my kit - about as bad as when someone uses the last roll and doesn't restock. All I had at the bench were my experimental ones that are just a tad too wide for my converted .404 bar. In the end it didn't matter as the wood was not really MAC worthy. No new MAC pictures.

Felled six trees with an off brand, and cut and pulled two tops from the creek. Barely earned my lunch today. Surely didn't earn the two servings of coconut pie I downed.

After lunch I modified one of my pins and further filed the bar - so all is good to go next time.

Here are a few pictures from the 2015/2016 season.

I have no MAC at work pictures for the 2014/2015 season. Some here will remember this little interruption in November 2014. Our little miracle CDH granddaughter, Heidi. Thankful to say, she is now five, healthy and full of life.
IMG_0423.JPG

Spent several weekends with a PM800 on this train wreck. September 2015
IMG_3837.JPG

There a pump house under that mess.
IMG_0822.JPG

Whittled it down to this snag. Pump house survived.
IMG_3846.JPG

Then put it on the ground with the 800.
IMG_0840.JPG

TO BE CONTINUED.

Ron
 
Not MAC pictures, just a couple I took for all those on the other side of the forum that think 60cc saws are useless. Could have done the same with a 1010S.

Off-brand 59cc dicing a large Red Oak. October 2015
IMG_0929.JPG

First Load.
IMG_0944-001.JPG

Near disaster extracting an uprooted Oak hung in smaller Oak. PM800 January 2016
IMG_3882.JPG

Big one hit the bar.
IMG_3894.JPG

SP125C at work. February 2016
IMG_3912.JPG

End of a long day felling. PM800 February 2016
IMG_1108.JPG

TO BE CONTINUED

Ron
 
Finishing up the 2015/2016 season.

Testing the 800 after my AV mount mod. (Also creating a stump to drive my truck into). April 2016
IMG_1493.JPG

A/V mod. Replacing MAC's almost inaccessible "special screw". April 2016
IMG_1488.JPG
IMG_1490.JPG

Slicing a table top (failure - it became firewood as city hauled it to the wood lot before I finished). PM800 May 2016
IMG_1548.JPG


Ron

This valuable report is provided through the the generous support of MacNuts like you and Blind Squirrel Falling, one of America's greatest imaginary businesses
 
Inspiration! I have the seals in and the corrosion pits filled in on the starter cover on the PM60. The carb has been cleaned and kitted. I made the aluminum check valve case in the fuel cap work with a little red necking. Working on making a replacement for the muffler cover which was rotted away. When that's done, it's going back together.
 
Inspiration! I have the seals in and the corrosion pits filled in on the starter cover on the PM60. The carb has been cleaned and kitted. I made the aluminum check valve case in the fuel cap work with a little red necking. Working on making a replacement for the muffler cover which was rotted away. When that's done, it's going back together.

Fantastic! Looking foward to hearing your feedback. Glad your excited to get it fired up. The consistency in running is getting better with mine the more I use it.
I almost ran out of gas on the oak log in the first video.
 
Inspiration! I have the seals in and the corrosion pits filled in on the starter cover on the PM60. The carb has been cleaned and kitted. I made the aluminum check valve case in the fuel cap work with a little red necking. Working on making a replacement for the muffler cover which was rotted away. When that's done, it's going back together.

I have told the guys on the other side that if I could only have one saw it would be a 60cc saw. Many think I am nuts; I may be.

Back in the day when less popular NOS cylinders went unnoticed on eBay, I picked up a PM60 cylinder as the only bidder. Gave it to Bryan Plust some time later. I hope he made a runner with it.

Ron
 
Not MAC pictures, just a couple I took for all those on the other side of the forum that think 60cc saws are useless. Could have done the same with a 1010S.

Off-brand 59cc dicing a large Red Oak. October 2015
View attachment 780130

First Load.
View attachment 780131

Near disaster extracting an uprooted Oak hung in smaller Oak. PM800 January 2016
View attachment 780134

Big one hit the bar.
View attachment 780135

SP125C at work. February 2016
View attachment 780136

End of a long day felling. PM800 February 2016
View attachment 780140

TO BE CONTINUED

Ron

It was a nicer day farther south. If thats a ms361 in that picture I approve! Probably the saw that got me the bug of chainsaws .
I was issued one at work and really enjoyed tuning it up and using a saw with that type of power considering I started with a Homelite super 2. Honestly when I'm tinkering with the PM 60 I shoot to get similar performance as the old ms361 I used at work, it will never wind up as fast but just enjoyment and power feel.
 
Good eye. It is a 361 with some minor work by Terry Landrum. I love that little saw. I have many hours on an 036Pro. Quite of few hours on two 362s. After getting the 361 I parted company with the 362s.

Ron
Totally agree, I don't own one yet, probably because I started snatching up as many old saws as I could afford after I caught the bug, but I do have my eye on a couple that pop up on craigslist.
My E.D.C. are pm700 and the 028 , funny how a 60cc would fit right in the middle!
 
Last summer while on vacation, I located on CL two beautiful 361s in south Florida, one on east coast and one on the west coast- what I call DIY storm cleanup saws. Almost no visible use, carrying case, manual etc. One was almost close enough for the drive but I didn't have enough time. Keep your eye out and you can find them reasonably priced. Ron
 
Finishing up the 2015/2016 season.

Testing the 800 after my AV mount mod. (Also creating a stump to drive my truck into). April 2016
View attachment 780141

A/V mod. Replacing MAC's almost inaccessible "special screw". April 2016
View attachment 780143
View attachment 780142

Slicing a table top (failure - it became firewood as city hauled it to the wood lot before I finished). PM800 May 2016
View attachment 780146


Ron

This valuable report is provided through the the generous support of MacNuts like you and Blind Squirrel Falling, one of America's greatest imaginary businesses

What AV mod did you do Mr Woods?

Nice pictures as always even the off brand and the little 1 too

In the Mac time warp at the moment young Kyle was talking about making some extra tough adjuster nuts did he ever get to it?
 
What AV mod did you do Mr Woods?

Nice pictures as always even the off brand and the little 1 too

In the Mac time warp at the moment young Kyle was talking about making some extra tough adjuster nuts did he ever get to it?

For quite some time, I tried to no avail to get the specs on MAC's screw described in the IPL as "special screw" which was missing from some of my project saws so I began substituting an Allen socket head screw. I also struggled reassembling the saws with the rear A/V mounted to the cylinder since it is hard to access the special screw if you mount the A/V to the tank first and is impossible with an Allen socket head screw. So I drilled a hole smack in the middle of the ID plate. This also allows you to mount the A/V to the tank first. After inserting and tightening the socket head screw I plugged the hole with a plastic plug. As life would have it I was later able to source some of the "special screws".

IMG_1482.JPG

IMG_1472.JPG

Ron
 

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