McCulloch Chain Saws

[mchamp]

I used a piece of fuel line tubing and got it repaired. Thanks for the information. Tom

Also if anyone needs flatback carberator parts Bob Johnson with Bob's lawnmower repairs has all the parts and can look up with the part numbers on the carb and the saw. He's the only person I talked to that knows all the correct part numbers I've found.

 

[vinnywv]

Yep bobs great to deal with.

 

[PogoInTheWoods]

​

 

[PogoInTheWoods]

Pulled the sp81 out tonight to play a bit. What is max unloaded rpm for these? I've often wondered. Mine pulls about 11,200 on a tach unloaded. My saw has an orange Atom chip.

The only top end no load spec for the 82cc saws that I've ever seen is for a PM8200 at 12,000 in a publication I posted a few pages back. Some may say that's getting a little close to the edge depending on what your ears may be telling you otherwise.

 

[mogulmasher]

The only top end no load spec for the 82cc saws that I've ever seen is for a PM8200 at 12,000 in a publication I posted a few pages back. Some may say that's getting a little close to the edge depending on what your ears may be telling you otherwise.

Thanks Pogo. Yeah I think I could have tuned a touch more rpm into it, but figured I'd play it safe. Was also tuning it with 28" bar/chain which I'm sure is killing a few hundred rpm.
My reason for checking it with tach was the chip in it. The orange Atom chip says its for Yamaha kart motors and is unlimited. Not sure if that is the most ideal chip for the saw?

 

[Syncop8r]

Perhaps there's enough spring left that I can curl the end and reuse it.

Upon closer inspection, the other end is broken too.


I think I'll just get a new spring.

 

[Maintenance supervisor]

Upon closer inspection, the other end is broken too.
View attachment 969486

I think I'll just get a new spring.

I've replaced a few on some old saws lately, ebay has had some name brands from days go by that are a good deal. There's probably 100s of 1000s out there.

 

[Maintenance supervisor]

View attachment 969475​

Have you cut anything with that !? She's cherry.

 

[PogoInTheWoods]

That's her good side. The top handle has a few pretty nasty dings. I cut with it a few times after I rebuilt it. Quite an interesting experience and there's some documentation about it in a couple threads -- mainly about cleaning up the top end, including cleaning up and reusing a fairly nasty piston..., and fixing a pretty hosed up starter assembly. Would still like to put a new piston in it one of these days. Not easy to find one. Not cheap when you can. A place called MandD near me was one of the only places that was offering them. Wish I'd have known Bob J. back then. He told me they were getting them from him. Said he may still have a couple hidden somewhere last time I talked to him a couple years ago. Probably long gone by now. Wouldn't be surprised if something else would swap right in given enough research on possible candidates being it's a modern day setup for a small rod end with needle caged wrist pin and clips.

 

[clint53]

Road trip today, But I didn't come back with anything like Mark did.
My kind of saws. I hardly ever by a running saw. I want to make it run myself.
Anyone can buy a running saw. That's not me.
So, somewhere in this pic is a running cutting PM850.
But, but, but, I left behind probably a short bed pickup full of Macs and Mac parts.
I saw 700's, 10-10's, 555's, 2-10's, 610's and a 1-71. Boxes of yellow parts and more saws I didn't ID.
I was pressed for time, but I'm going back to make an offer on everything.
I won't sleep well tonight.


The only thing I'm missing that I would have liked to have is a third coil.
Clint

 

[heimannm]

That's still a pretty nice haul.

Mark

 

[Maintenance supervisor]

Road trip today, But I didn't come back with anything like Mark did.
My kind of saws. I hardly ever by a running saw. I want to make it run myself.
Anyone can buy a running saw. That's not me.
So, somewhere in this pic is a running cutting PM850.
But, but, but, I left behind probably a short bed pickup full of Macs and Mac parts.
I saw 700's, 10-10's, 555's, 2-10's, 610's and a 1-71. Boxes of yellow parts and more saws I didn't ID.
I was pressed for time, but I'm going back to make an offer on everything.
I won't sleep well tonight.

View attachment 969494
The only thing I'm missing that I would have liked to have is a third coil.
Clint

That is an epic haul!

 

[rwoods]

Thanks Pogo. Yeah I think I could have tuned a touch more rpm into it, but figured I'd play it safe. Was also tuning it with 28" bar/chain which I'm sure is killing a few hundred rpm.
My reason for checking it with tach was the chip in it. The orange Atom chip says its for Yamaha kart motors and is unlimited. Not sure if that is the most ideal chip for the saw?

No chain - 12300 to 12500 seems okay per Brian and my earlier tests. In a later test with chains the rpm’s are much lower. See below. Except as noted none of the saws were retuned for the higher ambient temperature so they should have been a bit rich.
Ron

CONTENT WARNING​

Those who wear white lab coats, NASA employees and any who want verifiable/repeatable results may find this post offensive – all others read at your leisure.

Yesterday, Brian and I took some MACs out to play – no falling, bucking or brush work, just play.

LINE-UP:
View attachment 840294

PROCEDURE: Saws with chains in place run at no load full throttle to record rpm. Saws are then put to the wood. Operator indicates when he thinks saw is in its sweet spot. Brian runs B saws while Ron records rpm and Ron runs R saws while Brian records rpm. Bars buried in 32” to 36” Red Oak except over 28” bars as extra wood didn’t seem to matter. Minimum of 30” of wood on long bars.

Legend to the results: B = Brian’s saw, R = Ron’s saw. SP = sprocket nose, HN = hard nose, RN = roller nose. Under 90cc classes are .375” pitch unless indicated .404”; 90cc class and 120cc class are .404”. McCulloch saw unless indicated as OB or CC. OB = Off-Brand, CC = China Com. All stock unless indicated as Modified. DSP = 82cc with DSP from factory. All 7 pin except as noted.

RESULTS:

Mid 50cc to Mid 60cc Class:

B – 1010S 20” SN – Maximum 11,200 Sweet Spot 8,540
B – 55 16” SN – Maximum 9,130 Sweet Spot 6,800
B – 1010 20” SN – Maximum 10,800 Sweet Spot 8,000
B – 262 OB 20” SN – Maximum 13,700 Sweet Spot 9,500
R – 036 Pro OB 20” SN – Maximum 11,700 Sweet Spot 7,820
R - 361 OB Modified 20” SN – Maximum 11,270 Sweet Spot 8,170
1/8 turn leaner – Maximum 12,100 Sweet Spot 9,200

70cc Class:

R - 700 20” SN – Maximum 10,900 Sweet Spot 6,500

80cc Class:

B – 800 28” .404” SN – Maximum 9,380 Sweet Spot 6,500
B – 805 24” SN DSP – Maximum 9,700 Sweet Spot 7,400
R – DE80 24” SN DSP – Maximum 10,590 Sweet Spot 8,700
R – 800 33” SN – Maximum 9,720 Sweet Spot 7,190
R – 800 24” SN – Maximum 9,230 Sweet Spot 7,800
R – 800 24” SN DSP – Maximum 10,500 Sweet Spot 7,600 (8 pin)
R – 800 Modified 25” SN .404” – Maximum 10,200 Sweet Spot 8,025
R – 805 28” SP DSP – Maximum 8,270 Sweet Spot 6,400
R – CS8000 OB 24” SN – Maximum 11,050 Sweet Spot 7,300
1/4 turn leaner – Maximum 11,920 Sweet Spot 8,060

90cc Class:

B – 660 CC 36” SN – Maximum 12,100 Sweet Spot 8,000

120cc Class:

B – 125C 36” SN Adjustable jet – Maximum 8,300 Sweet Spot 7,350
R – 125C 33” SN Adjustable jet – Maximum 8,040 Sweet Spot 7,400 (8 pin)
1/8 turn leaner – Maximum 8,320 Sweet Spot 7,400
1/4 turn leaner – Maximum 9,730 Sweet Spot 8,400
R – 125C 36” SN Fixed jet GEM kart muffler – Maximum 10,050 Sweet Spot 9,490
R – 125C 42” HN Fixed jet – Maximum 8,400 Sweet Spot 7,670
R – 125C 54” RN Fixed jet – Maximum 10,000 Sweet Spot 8,640

Unscientific Take Aways:

Higher speed doesn’t translate into faster cutting as feed rate varies. 125s were leaned on hard. 90+cc CC and 82cc MACs were leaned on. CS8000 took a delicate touch, close to pulling up – seemed it had more chain than the saw wanted (new chain and off the same roll as R’s smaller OBs and 700 were running – also new - Go Figure). Small OB saws needed much more finesse than small MACs.

1010S is a strong running saw.

All saws initially tuned for winter (i.e. 40+ degrees F. cooler). Those re-tuned gained 800 to 1700 in maximum rpm and 750 to 1000 rpm in their sweet spot.

Bar length doesn’t matter much on a 125C. Nor does a hard nose.

125C are the easiest saws to start.

With the right jet, a fixed jet 125C is no slouch.

Don't let a "governed" DE80 fool you.

MACs will run even after sitting for years. The longest bar 125C had 9 year old gas in it from its last run; dumped most of it and used fresh mix. Several of the other MACs had not been run in two years or more. Some had old gas; others had evaporated dry. Even while burning copious amounts of bar oil, a 82cc MAC just keeps going.

I have too many 82cc MACs. Same for the 125C.

Have a safe and HAPPY 4th!

Ron

 

[rwoods]

Road trip today, But I didn't come back with anything like Mark did.
My kind of saws. I hardly ever by a running saw. I want to make it run myself.
Anyone can buy a running saw. That's not me.
So, somewhere in this pic is a running cutting PM850.
But, but, but, I left behind probably a short bed pickup full of Macs and Mac parts.
I saw 700's, 10-10's, 555's, 2-10's, 610's and a 1-71. Boxes of yellow parts and more saws I didn't ID.
I was pressed for time, but I'm going back to make an offer on everything.
I won't sleep well tonight.

View attachment 969494
The only thing I'm missing that I would have liked to have is a third coil.
Clint

The saws on the left and right appear to be newer 82cc MACs with 850 AF covers. Great saws none the less.
You are going to be busy for a long time. Congratulations!

Ron

 

[heimannm]

The mufflers are good indicators, aren't they?

Mark

 

[mogulmasher]

Thanks for the info Ron. Sounds like compared to your results 11200 out of a sp81 with 28" bar/chain is pretty good. I know the 81 is a strong runner. When I rebuilt it I smoothed out the exhaust port, port matched the muffler flange and gasket, and smoothed the sharp sheet metal edge where the exhaust enters the muffler box. Suppose these mods are worth a few rpms.

 

[rwoods]

The mufflers are good indicators, aren't they?

Mark

Yes. Side DSP and the end covers.
Ron

 

[clint53]

That's still a pretty nice haul.

Mark

Many thanks Mark.

 

[clint53]

The saws on the left and right appear to be newer 82cc MACs with 850 AF covers. Great saws none the less.
You are going to be busy for a long time. Congratulations!

Ron

Thanks Ron.
I haven't had time to check them out much. One didn't have a carb on it and the piston on the intake side looked great.
The guy is an 87-year-old retired logger. If he is the only one to run them, they all may be in good condition.
I'll take the plug out tomorrow and use the endoscope to take a better look.

Clint

 

[clint53]

That is an epic haul!

Thanks.
I'm pumped. They may look like junk to some, but not me.