McCulloch Chain Saws

[heimannm]

1-41

The 1-41 shares a lot of parts with the 200/250, almost everything for the saw would be available either NOS or a good replacement part from another saw. The 1-40/41/42/43 had bushings in the piston for the wrist pin where later models (1-45/46 and the 200's etc.) had bearings.

80 cc's and plenty of torque. Not sure but I think most early 1-4X models had the cup choke set up, a plunger you pushed with your thumb rather than a butterfly like most later models.

Manual oiler only, be prepared to wear out your thumb while cutting.

Mark

 

[hoss]

Hey all my dad has a pro MAC 600 and we were trying to find the specs on it. Weight, hp, c.i.'s, etc. If any of you know that it would be great thanks.

I've picked up a few numbers up in my reading over the years. If you are talking about a saw in the 605/610/650 series then the hp for the 610 is 3.5. The 87cc model super 44A is rated at 6.5 (which is pretty good when you consider that the modern Stihl 660 is 92cc and 7hp). I have seen some literature that suggests that the very early 120cc model 73 was 8-9hp, but not sure. The mac 125 at 123cc is of course a saw that has had much debate, but the most common number I have been able to get is between 9-10hp (which would mean that a 797 is probably a sloid 10-10.5hp), but I have not seen exact numbers in literature about it. Now even though the 10-10 family of saws up to the 82cc ones didn't have as good sound muffling or av as todays saws, they were very strong and I would say from experience that they are comparable within size classes to todays saws in hp and probably a bit stronger. I would personally feel better running a 32" bar on an SP81 than a new dolmar 7900 (though it is a nice saw).

 

[promac850]

I've picked up a few numbers up in my reading over the years. If you are talking about a saw in the 605/610/650 series then the hp for the 610 is 3.5. The 87cc model super 44A is rated at 6.5 (which is pretty good when you consider that the modern Stihl 660 is 92cc and 7hp). I have seen some literature that suggests that the very early 120cc model 73 was 8-9hp, but not sure. The mac 125 at 123cc is of course a saw that has had much debate, but the most common number I have been able to get is between 9-10hp (which would mean that a 797 is probably a sloid 10-10.5hp), but I have not seen exact numbers in literature about it. Now even though the 10-10 family of saws up to the 82cc ones didn't have as good sound muffling or av as todays saws, they were very strong and I would say from experience that they are comparable within size classes to todays saws in hp and probably a bit stronger. I would personally feel better running a 32" bar on an SP81 than a new dolmar 7900 (though it is a nice saw).

Hi hoss... looking to pick your brain a little bit more, if you don't mind. What are the horsepower specs for the Pro Mac 850 and 790? I has them and am curious if you happen to have that information. Thanks in advance.

 

[WKEND LUMBERJAK]

McCulloch 640

Does any one know if there is a carb. kit for McCulloch 640. I am working on one for a guy from work. It runs with a prime. The carb looks like nothing I have seen before. I haven't taken carbapart yet. Itmay just need cleaning. Any and all suggestions are appreciated. This saw sounds like a beast while it runs.

 

[promac850]

Does any one know if there is a carb. kit for McCulloch 640. I am working on one for a guy from work. It runs with a prime. The carb looks like nothing I have seen before. I haven't taken carbapart yet. Itmay just need cleaning. Any and all suggestions are appreciated. This saw sounds like a beast while it runs.

Pic would be extremely helpful. If it's a carb you've never seen before, it's likely one of those Mac specialty carbs, like the bullfrog or flatback... (experts, correct me if I am wrong on anything...)

 

[WKEND LUMBERJAK]

I will try to get a picture posted. I have not had much luck with posting pictures. But I will give it a try again.

 

[cpr]

On the subject of horsepower and rpm figures, I believe I have backed into some answers sought by an English butcher who peppered our collective inboxes in the not too distant past.

I found out (from a 'net source so your mileage may vary, but I do maintain a level of trust with where it came from) where the revs and hp are on the 101s.

Disclaimer: You can NOT hit this in a saw chassis without going yard. That means dual carbs, pipe, methanol, the works.

I have read that a sprint 101 was geared to runout at 13500 rpm on the longest straights. Around 13200 or less for an enduro. As for horsepower (for the record, due to my tractor pulling experience and knowing personally some folks with dynos, I am predisposed to be leery of HP numbers), it seems anything under 40.0 would induce snickers...

Seems over the top to me as a number, but at 125mph, it takes some snot to go that FAST.

Flame suit on, but there it is.

 

[promac850]

On the subject of horsepower and rpm figures, I believe I have backed into some answers sought by an English butcher who peppered our collective inboxes in the not too distant past.

I found out (from a 'net source so your mileage may vary, but I do maintain a level of trust with where it came from) where the revs and hp are on the 101s.

Disclaimer: You can NOT hit this in a saw chassis without going yard. That means dual carbs, pipe, methanol, the works.

I have read that a sprint 101 was geared to runout at 13500 rpm on the longest straights. Around 13200 or less for an enduro. As for horsepower (for the record, due to my tractor pulling experience and knowing personally some folks with dynos, I am predisposed to be leery of HP numbers), it seems anything under 40.0 would induce snickers...

Seems over the top to me as a number, but at 125mph, it takes some snot to go that FAST.

Flame suit on, but there it is.

:jawdrop: 125 MPH kart!! Holy :censored: that is fast for such a small amount of cc's. I have seen the GSX-R 600 karts going that fast on youtube, but those are a four banger four stroke, 600cc and a 101? cc kart engine can go as fast or faster and turn better, holy crap, now I want a kart with one of them built up 101's in it... someday, I will get one... someday...

 

[cpr]

:jawdrop: 125 MPH kart!! Holy :censored: that is fast for such a small amount of cc's. I have seen the GSX-R 600 karts going that fast on youtube, but those are a four banger four stroke, 600cc and a 101? cc kart engine can go as fast or faster and turn better, holy crap, now I want a kart with one of them built up 101's in it... someday, I will get one... someday...

A fella I used to work with raced single cylinder shifter karts. 125mph was a walk in the park for him.

 

[promac850]

A fella I used to work with raced single cylinder shifter karts. 125mph was a walk in the park for him.

Damn, gotta talk to that guy some day, face to face. He's gotta have some good stories and tips for making stuff go fast. I wanna talk to all of you in person, but am not sure if I will be able to either attend or hold a GTG this summer.

 

[54stude]

As a horsepower reference, I used to help crew with a guy who ran 100cc yamaha air cooled enduro carts in the mid 90's. With a carb that was similar in size to a saw, and a big tuned pipe I think the horsepower was something like 17hp at 18,000 rpm. It seems to me like he ran it so lean (tune it on the straights for max rpm with a tach on the steering wheel) that he had aluminum transfer from the piston to the cylinder about every 3 races. Lots of new pistons!

The shifter carts are a little different, usually a basically stock water cooled 125 dirt bike motor (around 40 horsepower stock). The shifter carts are made to run hard with minimal maintanance, and they corner and brake as hard as an indy car, really brutal little machines, not toys at all!

 

[homelitejim]

you guys weren't kidding when you said old McCulloch saws need to be tuned in the wood. Thought I had the ole 250 running good on the bench but took it out to the log deck and it fell flat, had to lean out the low and fatten the high by quite a bit. Was kind of worried at first that the old girl was tired, but a couple adjustments and she purred right up in the cut. Will have to do a bit of fine tuning to get the full 6000 rpm but I think I am close. Hopefully have a video tomorrow as I lost the light this evening. Serial # is 12091 with 11 prefix and good ole 250 # on bottom 62481. On a side note I switched out the .404 sprocket for a 3/8 as I have only one .404 chain and it is too long for any of my Mac bars but I do have lots o' 72 driver 3/8 chains lying around for my 20" hard nose mac bar.

 

[cpr]

As a horsepower reference, I used to help crew with a guy who ran 100cc yamaha air cooled enduro carts in the mid 90's. With a carb that was similar in size to a saw, and a big tuned pipe I think the horsepower was something like 17hp at 18,000 rpm. It seems to me like he ran it so lean (tune it on the straights for max rpm with a tach on the steering wheel) that he had aluminum transfer from the piston to the cylinder about every 3 races. Lots of new pistons!

The shifter carts are a little different, usually a basically stock water cooled 125 dirt bike motor (around 40 horsepower stock). The shifter carts are made to run hard with minimal maintanance, and they corner and brake as hard as an indy car, really brutal little machines, not toys at all!

Yup, like I said, my numbers were hearsay. I trust the revs, but not the hp... Shifter karts are psychotic contrivances and he ran his in classes shunning aero. Sorta like WoO cars without the nun-hats. Y'know, like this.

<iframe title="YouTube video player" width="480" height="390" src="http://www.youtube.com/embed/btsurAnCZRM" frameborder="0" allowfullscreen></iframe>

 

[Eccentric]

I've picked up a few numbers up in my reading over the years. If you are talking about a saw in the 605/610/650 series then the hp for the 610 is 3.5. The 87cc model super 44A is rated at 6.5 (which is pretty good when you consider that the modern Stihl 660 is 92cc and 7hp). I have seen some literature that suggests that the very early 120cc model 73 was 8-9hp, but not sure. The mac 125 at 123cc is of course a saw that has had much debate, but the most common number I have been able to get is between 9-10hp (which would mean that a 797 is probably a sloid 10-10.5hp), but I have not seen exact numbers in literature about it. Now even though the 10-10 family of saws up to the 82cc ones didn't have as good sound muffling or av as todays saws, they were very strong and I would say from experience that they are comparable within size classes to todays saws in hp and probably a bit stronger. I would personally feel better running a 32" bar on an SP81 than a new dolmar 7900 (though it is a nice saw).

Hiya Ian,

Did you happen to see what the McCulloch 77 was rated at? I'm curious whether or not it was stronger than the 73 since I believe the carburetor and air filter setups are quite a bit different between those two 7.3ci saws (unless I'm mistaken).

Mark H has my 77 now. The P/C are in great shape, so I'm hoping he makes a good strong runner out of it. He has the carb to sort out. It lights on a prime...

 

[hoss]

Hi hoss... looking to pick your brain a little bit more, if you don't mind. What are the horsepower specs for the Pro Mac 850 and 790? I has them and am curious if you happen to have that information. Thanks in advance.

Well I haven't seen any exact numbers for either one, but judging by experience and the numbers on the ones I do know I would say 6-6.5hp for the 850 and probably 7-7.8hp for the 790. I recently rebuilt a 795 and have been using it quite a bit lin the last three weeks in mostly 20-48" oak, and I would say it definately has more guts than a Stihl 660, which is what I base my estimate on.

 

[hoss]

Hiya Ian,

Did you happen to see what the McCulloch 77 was rated at? I'm curious whether or not it was stronger than the 73 since I believe the carburetor and air filter setups are quite a bit different between those two 7.3ci saws (unless I'm mistaken).

Mark H has my 77 now. The P/C are in great shape, so I'm hoping he makes a good strong runner out of it. He has the carb to sort out. It lights on a prime...

Unfortunately I don't know enough about either saw to say for sure. I will say though that I hear a lot of people talk about saws being "unstoppable" and I have this to say. I think that the 3100 homie and 890/895 macs are faster and more user friendly but my 73 which was pretty healthy was the torquiest saw I have EVER used. I was amazed how hard you had to dig the spike in and push just to get it to come "on the pipe". I'd bet you could run a 10' sprocket nose bar on those if you had to.

 

[Eccentric]

Unfortunately I don't know enough about either saw to say for sure. I will say though that I hear a lot of people talk about saws being "unstoppable" and I have this to say. I think that the 3100 homie and 890/895 macs are faster and more user friendly but my 73 which was pretty healthy was the torquiest saw I have EVER used. I was amazed how hard you had to dig the spike in and push just to get it to come "on the pipe". I'd bet you could run a 10' sprocket nose bar on those if you had to.

Thanks for the info Ian. I was a bit sorry to see that 77 go, but Mark made it more than worth my while with our trade. At the time, I couldn't locate a metering diaphragm for it...........and was getting frustrated. The old beast was just too much of an 'orphan' for my patience level. I like running good 'ol Tillotson HL's on all my big saws. Mark has since scored an NOS metering diaphragm for the 77, so there shouldn't be much holding him back now...

The thing sure sounded healthy. IIRC, the gear ratio on that saw is over 3/1. It doesn't have a governor (unusual for a gear drive of that time period) either. The saw had a 26-28" bar and a loop of Oregon 16C 5/8" chipper. I'd bet it it could easily pull four times that much bar if it was wearing 1/2" chain. As it is, I hope Mark gets it going (and soon....LOL).

I'd love to see video of it throwing huge chips with the big 5/8" chain. He may make it to the PNW GTG in June too. If he can, and that 77 makes the trip with him in running condition (and I get to make a few cuts with the old beast) then I'll be happier than a hog in slop!:hmm3grin2orange:

 

[heimannm]

...if I ever get to spend a day at home again...the 77 is the next thing up. Schedule has been pretty full the last few weeks.

for the WEEKEND LUMBERJACK, click on the link to the McCulloch Carburetor thread below.

Mark

 

[betterbuilt]

The 1-41 shares a lot of parts with the 200/250, almost everything for the saw would be available either NOS or a good replacement part from another saw. The 1-40/41/42/43 had bushings in the piston for the wrist pin where later models (1-45/46 and the 200's etc.) had bearings.

80 cc's and plenty of torque. Not sure but I think most early 1-4X models had the cup choke set up, a plunger you pushed with your thumb rather than a butterfly like most later models.

Manual oiler only, be prepared to wear out your thumb while cutting.

Mark

I noticed the crazy thumb plunger. Thanks for all the info on the saw.

 

[promac850]

Well I haven't seen any exact numbers for either one, but judging by experience and the numbers on the ones I do know I would say 6-6.5hp for the 850 and probably 7-7.8hp for the 790. I recently rebuilt a 795 and have been using it quite a bit lin the last three weeks in mostly 20-48" oak, and I would say it definately has more guts than a Stihl 660, which is what I base my estimate on.

Thanks for the info! I now have a better idea of what these big Macs should be capable of. Nothing like a big old Mac to chew through a tree.