Which Mac to build 2-10 or 1-70 or 4-30

[Leonard Meehan]

I have three old McCulloch chainsaws. I want to start a new project. The saws are mostly complete. I have no need for them to run. It is just a hobby for me. Right now they are yard art and they have all been run hard back in the day. Which one would be more fun or interesting to restore. The 4-30 says it is a one man saw. I would like to meet this man. Mac was so proud of the 4-30 it was named for having 4 hp and only 30 pounds. In just 5 years they came out with the same 87cc in the 1-70 and 19.5 pounds.

Has anyone run either saw? You comments would be appreciated

Thank for your input.
s there a mac group I should post in?

 

[Sepia]

I think the 4-30 would be an awesome build thread. Not something you read about or see very often.

 

[heimannm]

Check out the McCulloch thread in the Chainsaw Stickies section.

The 2-10 probably has a "bull frog" carburetor, diaphragms are available but the duckbill valves are not available anywhere. I have been able to modify the carburetor body by drilling it out a bit to accept the red Homelite duckbill valve. There should be a McCulloch 10 Series Carburetor thread somewhere.

The 1-70 will have a Tillotson HL carburetor, kits are readily available and other bits like the fuel line can be replaced easily enough. The 1-70 was more of a torque saw compared to the D-44 which was capable of high RPM for the day (9,00o to 10,000).

The 4-30 is certainly the most unique of the lot with the rotary valve system. The carburetor is also quite unique. I might have a diaphragm that would fit but the gasket is broken if I remember correctly.

Mark

 

[Brent Adams]

+1 vote for the 4-30 rebuild.
I know, more aggravation for you.
If you dont need it to work with, it would be a challenge, as well as a learning experience for those that may one day want to restore one of these to running condition for nostalgic reasons, or as a tribute saw for a loved one.

 

[rwoods]

Not going to vote but I will say Mark had an old MAC at a Tennessee GTG which felt to be anchored to the ground when I picked it up. I want to say that it was a 77. Ron

 

[Woodslasher]

4-30! I wanna have a rough idea of how my 47s and 73 are put together before I dig into them! Then do the 1-70 and finally the 2-10. Which reminds me, can anyone tell me how many turns out the butterfly adjuster screw in a 2-10 sdc carb should be set at? I accidentally screwed up mine and now the saw loads up for 3 pulls and on the 4th pull it lets out a pow and a cloud of white smoke. Also, https://www.arboristsite.com/community/threads/mcculloch-chain-saws.71126/page-1703 is the place to go for Mac help.

 

[heimannm]

Check this out.

Mark

 

[Woodslasher]

Need me to hold your beer ? On a more serious note, thank you for posting that. It tells me exactly what I need to know.

 

[Leonard Meehan]

Check this out.

Mark

Thanks for the Carb manual this is just what I needed. I like to understand how things work.

 

[Leonard Meehan]

4-30! I wanna have a rough idea of how my 47s and 73 are put together before I dig into them! Then do the 1-70 and finally the 2-10. Which reminds me, can anyone tell me how many turns out the butterfly adjuster screw in a 2-10 sdc carb should be set at? I accidentally screwed up mine and now the saw loads up for 3 pulls and on the 4th pull it lets out a pow and a cloud of white smoke. Also, https://www.arboristsite.com/community/threads/mcculloch-chain-saws.71126/page-1703 is the place to go for Mac help.

Thanks for the link I have been reading posts since 2 am. A lot of good information.

 

[Leonard Meehan]

I found a Pro Mac 510 in the box of saws to rebuild. It is complete just dirty. I think I may just put it back together and tune it up to get my Mac feet wet. The 2-10 I took a look at and it has a weld on the engine mount. Boy are these saw tough. The recoil starter was so gummed up it would not return. When I get it cleaned up I will check for compression and spark and then think about it.
The 4-30 has the most interest for me because it is old and heavy. Right now It is in the front yard as yard art. I also let people pick it up to show them what a REAL saw feels like. I has some missing parts so I think i will do an inventory and will need some help in locating and identifying parts. If it were not for you guys being so generous with you knowledge I probably would not attempt it.

 

[Leonard Meehan]

I am also a old car nut. When I found out that you don't have to crawl under a chainsaw to rebuilt it I switched to saws. I have worked on paxton blowers and until now did not know that Robert Paxton McCulloch built them. And he built drone engines for WWII, Here is a fun history about McCulloch motors.
http://vs57.y-block.info/history.htm
I think this is McCulloch testing a 4-49

 

[heimannm]

That saw is a 3-25, notice how the wrap handle terminates in the flywheel housing.

Mark

 

[Leonard Meehan]

HELP needed with the Mac 2-10 Carburetor rebuild. I decided to start with the Mac 2-10. It was complete and I found the single needle carburetor very interesting
It has spark and compression. I runs with fuel down the carb. Fuel squirts out the inlet hole when the primer is pumped. I am guessing that the check valve is dirty or stuck.
I took the carb apart. The diaphragm look ok. The primer plunger did not come out and I do not want to force. Thanks to mark I have the rebuild manual.
It look like I have a single needle carb. Is this correct?
It looks like I have to remove the plunger from the rod end. What is the best way?
Do I have a type 3 with cup to hold the O ring in place.
The filter screen has a lot of crud on it. Should I remove it or not.
Thanks for any help.

 

[Leonard Meehan]

HELP needed with the Mac 2-10 Carburetor rebuild. I decided to start with the Mac 2-10. It was complete and I found the single needle carburetor very interesting
It has spark and compression. I runs with fuel down the carb. Fuel squirts out the inlet hole when the primer is pumped. I am guessing that the check valve is dirty or stuck.
I took the carb apart. The diaphragm look ok. The primer plunger did not come out and I do not want to force. Thanks to mark I have the rebuild manual.
It look like I have a single needle carb. Is this correct?
It looks like I have to remove the plunger from the rod end. What is the best way?
Do I have a type 3 with cup to hold the O ring in place.
The filter screen has a lot of crud on it. Should I remove it or not.
Thanks for any help.

UPDate. I got the plunger out but can not get the needle and seat out. I did not find the primer check valve can i use a homelite duckbill valve? Any tricks to get the primer seat out.
The manual said to bang it on a hard surface which i did.