McCulloch Chain Saws

[Roanoker494]

I just bought a new 34" Mcculloch bar to put on my pm1000. Does anybody know how many links of 3/8" chain that I need for it?

Jeff

110DL is what a Oregon branded large mount Husqvarna bars uses but it will depend on what manufacturer made your McCulloch bar.

 

[cpr]

I give auto oiler, but I see decomp. Wrap looks fine to me, just no rubber left?

 

[Eccentric]

106DL of 3/8" is what a McCulloch 33" bar would take. Not sure about 34". Probably 107-108DL.

 

[copeland]

McCulloch 250

I've got a 250 that my great-grandpa bought new in 1963, even still have the original manual. Old heavy beast that has seen a LOT of action, as my great-gpa AND gpa were both loggers throught the 60s and 70s. It then cut firewood for two generations. I now have it, it is finally worn down (clutch is bad, carb issues, etc.) but I want to restore her. Family heirloom. I just can't seem to find new parts for it. Any help?

 

[Roanoker494]

Plenty of good used parts on Ebay and there are some others models with interchangable parts, like the 1-50.

 

[jeff76]

Don't the specs for the bar state how many DL are required?

BTW, please post vid or let us now how that saw pulls 34" ..... sweet cutting saw ... "Like cutting wood with a Buick."

I figured that it would say on the bar also, but it doesn't have anything about drive link #. Just guessing, I would say eccentrics 107-108 sounds close. I figured someone else maybe had one and could tell me what they had. I don't have any way of recording a video(still in the dark ages), but I'll let you know whenever I try it out. I have a p100 with a 36" bar on it, so I'd say it should handle the 34" bar O.K.

Jeff

 

[copeland]

Thanks, Roanoker494, I didn't know the 1-50 had interchangeable parts. I don't know a whole lot about the dinosaur saws, but I sure like them! Do you know of any others that have interchangeable parts?

 

[Eccentric]

I've got a 250 that my great-grandpa bought new in 1963, even still have the original manual. Old heavy beast that has seen a LOT of action, as my great-gpa AND gpa were both loggers throught the 60s and 70s. It then cut firewood for two generations. I now have it, it is finally worn down (clutch is bad, carb issues, etc.) but I want to restore her. Family heirloom. I just can't seem to find new parts for it. Any help?

What's wrong with the clutch? If it's a non-super 250 (the S-250 is a different saw), then it will have a clutch assembly that threads onto a non-tapered crankshaft. Saws with this crankshaft design include the 15, 200, and 250. Maybe some older front-tank models too.

The S-250 has a tapered shaft (with a key) and the clutch is held onto the shaft with a nut. Tapered shaft saws include the S-250, 300, 380, 440, 450, 550, S-550, and most of the 1-70 and later top-tank saws. Maybe more.

If you have a 'standard' 250 (and have a threaded crankshaft), then I can send you a clutch hub/shoes/spring assembly for the cost of shipping. I don't have any spare tapered shaft clutches. Just don't call them dinosaur saws anymore!

Does your carb say "tillotson" on it anywhere? The first 250s had McCulloch "flatback" carbs. After 1964, the standard 250s had Tillotson HL's. The HL takes an RK-88HL carb kit that you can find anywhere. Fuel lines will be 3/16" ID Tygon in the tank, and 3/16" or 1/4" ID automotive line between the tank and carb.

 

[briantutt]

Brian

 

[rwoods]

Arrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr!

:bang::bang::bang::bang::bang::bang: Ron

 

[rwoods]

While I was laid up last winter I brought a load of firewood which was cut longer than represented and would not fit in my stove. I thought I would cut the stack in half today with my favorite 800. I thought it was running way too fast but dismissed it to the small diameter wood and what the heck I was only going to be cutting for a few minutes at a time. Well I only ran it a few minutes and it quit just like last Saturday (fouled plug). The compression seemed light so I thought I would check before putting in the new plug I got today. 60 p.s.i. I took the muffler off, and sure enough I had burned up my favorite saw. I guess I got it too lean last Saturday when I was tuning it after cleaning the fouled plug. I tuned it in bar length wood and fatten it up about an 1/8 turn. I can’t hear 4 stroking as is so often described and videoed here so I just adjusted the high side to the highest in wood rpm then I richen it a little. This is the first that I have ever toasted. I run 32/1 mix using S***l Ultra. I feel like an idiot, as I knew the saw was screaming. And it being my favorite 800 just makes it worse. The only good is I don’t have to take the time to take the muffler off just to check for porting and I don’t have to look any longer for a donor saw for my NOS piston.
The exhaust has not been ported so maybe it was just the muffler that made this saw stand out among my 800s.
Ron

 

[Brian13]

Sorry to see you fried your saw Ron. From the pics it dosnt look too bad, might be able to get away with just rings and some good cleaning. Hard to tell from the pic though. Hope you get it back up and running.

 

[rwoods]

Thanks, Brian. The piston is melted on the clutch side. North of the coil in the pictures. The rings are completely covered in a small area. I don't know what it looks like from the intake. At least it is a "B" cylinder and I have a spare "B" piston. I hope the cylinder is okay as this was by far my strongest 800. Live and learn. I have no one to blame but myself. Ron

 

[Nardoo]

Nardoo, My guess is a 1-85, 1-86 or a 740.
But as you know the numbers are on the bottom
of the block that will tell the model.

Nice saw. Get her running, She's made for the big wood.

Lee

I looked at the numbers underneath and this is what they said:

Can anyone decipher that? I do not know anything about Macs but this seems like a neat old saw. I do not have much time at the moment but ia quick look shows it has great spark and 125lb compression. I suspect it will run but I won't try until I look inside.
And it has 9/16" chain which is Mac branded bet that is hard to get! I thought it looked bigger than the 1/2" chain on my C6.

Thanks for the help.

Al.

 

[leeha]

Nardoo, 63629 usually means the saw is
an 895. I can't really see a decomp. Doe's
it have one? It would be to the right of the
trigger handle behind the muffler.
I suspect maybe the short block was changed
at sometime.



Lee

 

[Nardoo]

Nardoo, 63629 usually means the saw is
an 895. I can't really see a decomp. Doe's
it have one? It would be to the right of the
trigger handle behind the muffler.
I suspect maybe the short block was changed
at sometime.

Lee

Lee, yes, it does have a decompressor.

 

[leeha]

Well then that would confirm it's an 895.
I'm sure if it could talk there would be some
stories to tell. Strange how there's no auto
oiler. Some parts were obviously swapped at
some point in it's life.




Lee

 

[heimannm]

I been out of touch for a few days, took some vacation time last week and went fishing among other things.

In my spare moments I have been working on the carburetor issues on one of the SP81's I tried to get ready for the GTG earlier in the month. This one in particular has the fixed high jet and at first was rather rich unloaded, then when we started cutting with it it would lean out badly. First step was to turn the fuel line over, seems to have a "set" in the line inside the tank that held the pick up off the bottom of the tank. As this one was a little loose where it passed through the tank, I put a few wraps of teflon tape around the molded in grommet and solved the leak...

Now sometime this saw would start and run just fine, other times it was be so flooded you had to lay it on it's side and crank and crank until all the excess fuel cleared. Even then it would still run very lean at WOT. I went through this carburetor a dozen times at least adjusting the metering lever height, lapping the needle and seat, replacing the needle and metering diaphragms, and still it would not seat properly and hold pressure like it should. Finally I got serious and used some valve lapping compound and chucked a short piece of small diameter tygon in the cordless drill that just slipped over the needle and really lapped it. No more leaks around the metering needle, but the carburetor would still not hold pressure.

Finally, taking some advice from an old McCulloch workshop manual I submerged the entire carburetor in a jar of solvent and pressurized it to find a few large bubbles coming from the impulse port and lots of tiny bubbles around the fuel pump cover. I tried replacing the fuel pump diaphragm but it still seemed to leak (bubbles, did not hold pressure). I remembered reading in the Walbro literature about the importance of the "crush ribs" on the fuel pump cover, and decided to change out the plain steel cover for a die cast one with the ribs.

Long story short, problem solved. No more leaks, holds pressure, starts and runs very nicely, and seems to be very good on the top end with some 4 stroking out of the cut.

I had a chance to try the saw on Saturday cutting up a large maple tree the boys helped me get down and cut up and wow, what a saw. I also ran my new Dolmar 7900 and I am sure that for all day cutting that will be a nicer saw to run, but for downright cutting pleasure the SP81 is very high on my list right now.

Mark

 

[Eccentric]

I been out of touch for a few days, took some vacation time last week and went fishing among other things.

In my spare moments I have been working on the carburetor issues on one of the SP81's I tried to get ready for the GTG earlier in the month. This one in particular has the fixed high jet and at first was rather rich unloaded, then when we started cutting with it it would lean out badly. First step was to turn the fuel line over, seems to have a "set" in the line inside the tank that held the pick up off the bottom of the tank. As this one was a little loose where it passed through the tank, I put a few wraps of teflon tape around the molded in grommet and solved the leak...

Now sometime this saw would start and run just fine, other times it was be so flooded you had to lay it on it's side and crank and crank until all the excess fuel cleared. Even then it would still run very lean at WOT. I went through this carburetor a dozen times at least adjusting the metering lever height, lapping the needle and seat, replacing the needle and metering diaphragms, and still it would not seat properly and hold pressure like it should. Finally I got serious and used some valve lapping compound and chucked a short piece of small diameter tygon in the cordless drill that just slipped over the needle and really lapped it. No more leaks around the metering needle, but the carburetor would still not hold pressure.

Finally, taking some advice from an old McCulloch workshop manual I submerged the entire carburetor in a jar of solvent and pressurized it to find a few large bubbles coming from the impulse port and lots of tiny bubbles around the fuel pump cover. I tried replacing the fuel pump diaphragm but it still seemed to leak (bubbles, did not hold pressure). I remembered reading in the Walbro literature about the importance of the "crush ribs" on the fuel pump cover, and decided to change out the plain steel cover for a die cast one with the ribs.

Long story short, problem solved. No more leaks, holds pressure, starts and runs very nicely, and seems to be very good on the top end with some 4 stroking out of the cut.

I had a chance to try the saw on Saturday cutting up a large maple tree the boys helped me get down and cut up and wow, what a saw. I also ran my new Dolmar 7900 and I am sure that for all day cutting that will be a nicer saw to run, but for downright cutting pleasure the SP81 is very high on my list right now.

Mark

Way to stick with it Mark! That's how I feel about my SP81. It has the fixed H side carb, but I'll swap in an SDC38A eventually. Not in a big hurry to do it right now though as it's running so well as is.

 

[heimannm]

Somehow I have managed to collect a whole box of SDC carburetors so it was easy enough to find one in good shape to make sure the saw would in fact run properly. In fact, continued searching turned up one with the "upturned" adjusting needles to make it easy to adjust in the saw. Now I have two freshly rebuilt SDC's on hand for the next project.

Even so, I wanted to try to make this one like the original if I could so I just kept at it and finally, success.

I'm not doing this on the clock so it's only my own time I am consuming, but gaining experience all the while. In the future, I will keep the jar handy and jump ahead to the leak test earlier in the process and save a little aggrevation.

Mark