McCulloch Chain Saws

[Brian13]

I wish I could afford what ever that 895/101 is going to go for. I would find a 895 block and pull the 101 out. Get my 6ci geardrive, and have a 101 to build a sweet kart saw.:msp_love:

 

[RandyMac]

The SP125 was detuned for the crappy gas in some areas. Put a 60" on both of them and the 797 will be finished first, but not long enough to get the tingle out of your fingers.

 

[hoss]

My Super 797 has benn consistantly faster than every 125 I have ever had no matter how healthy. I currently have three 125's and have run10 or 12 in my time.

 

[hoss]

Here is an updated list of my Mac stable:
Super 797 x 2 (one with 101B Kart motor)
125 x 3
895
890
795 x 2 (one with new rings & one with new piston/rings)
PM1000 x 2
550
650
1-60
There are many more, but these are the runners that I would be confident picking up and using all day. All the gear drives are converted to .404 and run roller nose bars and round chisel chain. If there are any you guys would like to see in a video that I don't already have on my youtube channel let me know.

 

[Brian13]

Here is an updated list of my Mac stable:
Super 797 x 2 (one with 101B Kart motor)
125 x 3
895
890
795 x 2 (one with new rings & one with new piston/rings)
PM1000 x 2
550
650
1-60
There are many more, but these are the runners that I would be confident picking up and using all day. All the gear drives are converted to .404 and run roller nose bars and round chisel chain. If there are any you guys would like to see in a video that I don't already have on my youtube channel let me know.

Whats the youtube link? I dont see any there that I wouldnt want to see a video of.

 

[RandyMac]

Hoss rocks and shares what he knows and learns with straight talk.

 

[hoss]

Whats the youtube link? I dont see any there that I wouldnt want to see a video of.

The youtube channel is "sawsell" you will want to look for videos that the title starts with the word "Hoss's", not the ones that start in "grr-illa".

 

[hoss]

Hoss rocks and shares what he knows and learns with straight talk.

Thanks Randy. I notice you don't beat around the bush much either. Man I love fallin timber/ runnin saws in general and your storie are motivating and interesting to hear, but i'd trade hearing all of em to have experienced half of em.

 

[Brian13]

Thanks Hoss, found it. Just watched the Hoss's Heavyweights video, if you can drop start a S797 like that I wont be picking any fights with you:msp_biggrin:.

 

[RandyMac]

The thought that you couldn't use a higher rev motor in a geardrive, banish it from your minds. Kart powered geardrives were used, for the same reasons direct drives got Kart motors. More speed, able to pull chain on truly long bars and of course, the sharp crackle from the exhaust.
There are "standard" geardrives with not so "truck" motors in them, the 660, Homelite 3100G, 895..........what is hot in a direct drive, will be hot in a geardrive.

 

[Eccentric]

The thought that you couldn't use a higher rev motor in a geardrive, banish it from your minds. Kart powered geardrives were used, for the same reasons direct drives got Kart motors. More speed, able to pull chain on truly long bars and of course, the sharp crackle from the exhaust.
There are "standard" geardrives with not so "truck" motors in them, the 660, Homelite 3100G, 895..........what is hot in a direct drive, will be hot in a geardrive.

Yep. And gear reduction means you're trading RPM on the clutch side of the gearbox for torque on the output shaft. You need less torque from that gear drive engine and more RPM's compared to a DD saw. A Kart engine fits that bill well.

An engine that favors upper RPM's, but that would struggle a bit in a DD application (sounds like a kart engine) would do extremely well in a gear drive, where output torque is multiplied 2-3X. You'd want to run good gear oil, and make sure the input bearings on the gearbox were in good shape though....

 

[8433jeff]

Yep. And gear reduction means you're trading RPM on the clutch side of the gearbox for torque on the output shaft. You need less torque from that gear drive engine and more RPM's compared to a DD saw. A Kart engine fits that bill well.

An engine that favors upper RPM's, but that would struggle a bit in a DD application (sounds like a kart engine) would do extremely well in a gear drive, where output torque is multiplied 2-3X. You'd want to run good gear oil, and make sure the input bearings on the gearbox were in good shape though....

As you should in any old equipment situation, unless you cannot afford to do otherwise, or its a matter of starvation or preservation of life.

 

[Eccentric]

As you should in any old equipment situation, unless you cannot afford to do otherwise, or its a matter of starvation or preservation of life.

That's certainly true Jeff. However, it's a bit more critical in this application methinks. What some may consider "good enough" in a standard occasional-use gear drive 'collector' saw may not pass muster in the high-RPM, high-stress configuration that's being discussed here...

 

[8433jeff]

That's certainly true Jeff. However, it's a bit more critical in this application methinks. What some may consider "good enough" in a standard occasional-use gear drive 'collector' saw may not pass muster in the high-RPM, high-stress configuration that's being discussed here...

Recommend an oil, Aaron, and what is the preferred choice in the manual?

 

[boda65]

The case of the rotating piston

I've posted a separate thread, but wanted to run it by the gurus who frequent this one.

I have my pro mac 800 apart to investigate a possible air leak. I noticed the piston will actually rotate in the bore, about maybe 1/16 of an inch on the circumference. Can anyone come up with a reason this would be acceptable? Seems to me the wrist pin would have to be sloppy, not good. This saw was not making any unusual noise when it started running poorly. It is also a very low hours unit, as it was NIB until last fall.
Jim

 

[Eccentric]

Recommend an oil, Aaron, and what is the preferred choice in the manual?

I believe 90W gear oil is recomended in the manual (I'm sure it's "McCulloch Chainsaw Gear Oil" or something similar). That would have been your basic 90W GL-1 spec gear oil back in those days (same as what was recomended for many manual truck transmissions at the time). In this case, since those kart engines turn 11K RPM or better (I'm just guessing the RPM's there) I'd go with a good synthetic gear oil, such as something from Redline or Royal Purple.

In my truck transmissions I run a good 50W motor oil, as the viscosity roughly matches 90W GL (different scales), it doesn't contain the EP additives that are corrosive to brass transmission parts such as synchros and bushings (probably not an issue here), and is cheaper than synthetic. For the saw gearbox I'd go synthetic...

 

[Eccentric]

I've posted a separate thread, but wanted to run it by the gurus who frequent this one.

I have my pro mac 800 apart to investigate a possible air leak. I noticed the piston will actually rotate in the bore, about maybe 1/16 of an inch on the circumference. Can anyone come up with a reason this would be acceptable? Seems to me the wrist pin would have to be sloppy, not good. This saw was not making any unusual noise when it started running poorly. It is also a very low hours unit, as it was NIB until last fall.
Jim

Could be the big end bearings in the rod as well. I don't know if these saws have the press-fit wrist pin with bearings in the piston (like the earlier big Macs) or if it has a wrist pin bearing in the rod and a 'normal' slip fit pin/piston arrangement. Seems a bit loose in any case. I'm eager to see some expert responses to this one...opcorn:opcorn:opcorn:

 

[rwoods]

I've posted a separate thread, but wanted to run it by the gurus who frequent this one.

I have my pro mac 800 apart to investigate a possible air leak. I noticed the piston will actually rotate in the bore, about maybe 1/16 of an inch on the circumference. Can anyone come up with a reason this would be acceptable? Seems to me the wrist pin would have to be sloppy, not good. This saw was not making any unusual noise when it started running poorly. It is also a very low hours unit, as it was NIB until last fall.
Jim

Could be the big end bearings in the rod as well. I don't know if these saws have the press-fit wrist pin with bearings in the piston (like the earlier big Macs) or if it has a wrist pin bearing in the rod and a 'normal' slip fit pin/piston arrangement. Seems a bit loose in any case. I'm eager to see some expert responses to this one...opcorn:opcorn:opcorn:

I'm neither a guru nor an expert - but I just checked an SP81 that I have disassembled. It has plenty of slop but it appears to be the rod bearings at the crank not the wrist pin bearings. Although your's is an almost NIB and mine a high mileage model, I wouldn't sweat it unless one of the real gurus/experts says differently. Ron

 

[cbfarmall]

A long-awaited acquisition, courtesy of a member here. Fired it up and have already taken notice of a nice, deep cackling at idle.

I can now retire from the saw collecting business and get back to my crappy IHCs.

Chris B.

 

[HeRoze]

A long-awaited acquisition, courtesy of a member here. Fired it up and have already taken notice of a nice, deep cackling at idle.

I can now retire from the saw collecting business and get back to my crappy IHCs.

Chris B.

==

Good ***, man- what a saw.