McCulloch Chain Saws

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Anyone have a clear idea of how to fix the leaking gas from the gas cap on a pro Mac 10-10? I have a new check valve in it. Correct part number. As well as a new but slightly distorted cork board gasket. When not distorted it leaked then too. Also installed a spring under the check valve from a fountain pen and clipped it short to have slight spring pressure. STILL leaks. Seems to be pressure related to when it’s set down upright and when it’s on its side. So, most of the time it just leaks. I have ordered a home lite XL12 gas cap and it does not fit. Has anyone tried a rubber gasket instead of cork? I don’t like how cork has to swell to work.
 
What I've found is that the 'newer' style caps - the ones that have a split in the middle, gas can on one side, oil can on the other - are the worst. They always leak, even when they're NOS. The best ones are the ones that are smooth and flat across the top. Why Mac couldn't figure out gas caps is beyond me.
 
I’ll give that a shot Mogul.

Luckily I have the smooth cap. I don’t think you can split it apart without prying with 2 screwdrivers. It is the non MC logo one and not the riveted one.
 
The saga of my $20 Super Pro 40 continues....suprises around every corner. I did get the spark working in part thanks to Mark's advice about the coil. It was in fact the terminal on the points assembly had rotated a bit and come into contact with the condenser bracket, grounding the spark!

This morning i managed to remove the crank to examine the radial play i can feel in the crank bearings, just hoping the crank looks good and just the needle bearings are worn.
I get the flywheel and clutch off, fight the woodruff key a little but it comes out (a little buggered, will need to file it smooth). Then I start removing the main cap bolts, when i get to the third one...its loose! Not just loose...the head isn't attached to anything...wtf?!

Sure enough, one bolt is broken. Luckily not flush with the block, the threaded part turns with my fingers. But wth...you guys ever seen anything like this??

Piston and cylinder look beautiful, no scuffs or scoring. Chrome looks good. I noticed no pins to index the rings in the piston?

Once i determine the crank is good, i will track down bearings and seals, and then put it back together and seal up the case with Yamabond. I really want this saw to be a runner!
 

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Had a recommendation from someone in another thread to post these pictures here. My dad picked up a PM650 at a yard sale for $20-it was clean as a whistle and the gas tank was dry as a fart. I ran it for a while with the 18" bar it came with but I needed something that would handle some bigger wood. I gave Lee at Lil' Red Barn a call and got a bunch of parts including a 24" bar with full chisel full skip chain and a tune up kit. I'm running it on 50:1 (my other saws are both Stihls) 100LL fuel which it seems to like so far. I also have a PM610/Eager Beaver that runs which I might put the old 18" bar on just for some variety. What is the operative difference between these saws since they are apparently both 60cc? Is it just the carb and/or the tuning? All shined up and 24" bar and skip chain fitted:

aiWsi8tl.jpg


Some of this week's bucking and splitting. Finally got around to working on some of the locust and cherry that fell during the "Four'Easters" in 2018-this is only about half of it. The trunks are about 20-22" in diameter so the 24" bar really helps. Looking forward to browsing this thread more and hopefully learning the difference between a 610 and a 650 as well as what parts interchange:

8DRKhFol.jpg

$20... stole it! I never get a deal that good.

I paid $20 for a broken SP40 and thought I did OK.

Some day I will find a deal on a 70+cc Mac for my collection.
 
You guys are killing me with these deals...
Your in New York, you should be in a hot spot of old saw treasure! I highly recommend stopping by small scrap/junk yards ,old farms ,and old saw shops.
Especially old saw shops even if they don't have anything older they usually know someone who does , you gotta Network like a pro! ( shake hands and kiss babies) .
Honestly for every 10 times I call or stop to talk to someone about a saw I might get a prospect, if you have business cards hand them out with your personal number written on the back. It can be fun and disappointing hunting for old saws but unless you've got expendable cash taking time to shoot the breeze is the best method for getting leads and sometimes making friends.
 
Your in New York, you should be in a hot spot of old saw treasure! I highly recommend stopping by small scrap/junk yards ,old farms ,and old saw shops.
Especially old saw shops even if they don't have anything older they usually know someone who does , you gotta Network like a pro! ( shake hands and kiss babies) .
Honestly for every 10 times I call or stop to talk to someone about a saw I might get a prospect, if you have business cards hand them out with your personal number written on the back. It can be fun and disappointing hunting for old saws but unless you've got expendable cash taking time to shoot the breeze is the best method for getting leads and sometimes making friends.
Finding old saws sounds a lot like finding a job!! haha

I think you are 100% right, I just have no time right now, 2 kids, 8 months old and 2 1/2, working full time.

Not long ago my dad went to an estate sale, he said inside a barn was a pile of old saws of all kinds. They probably went CHEAP.

In the future, I'm going to really look for big displacement Mac.
 
Finding old saws sounds a lot like finding a job!! haha

I think you are 100% right, I just have no time right now, 2 kids, 8 months old and 2 1/2, working full time.

Not long ago my dad went to an estate sale, he said inside a barn was a pile of old saws of all kinds. They probably went CHEAP.

In the future, I'm going to really look for big displacement Mac.
I like people so its pretty easy for me, but with what you got going on you time is pretty much spent. So if you just let people around you know you might get lucky ( work ,church, ect..)
Theres a member on here who was wearing a McCulloch hat and someone gave him an old McCulloch after recognizing the symbol on the hat. I can't remember who it was?
Give your Dad a spending limit and tell him to just grab them next time.
 
View attachment 826233

10-10 $23.00 ,fresh scrap yard score today.
Sweet Gum smashed one of my 10s last week, so I stopped to look for maybe a parts saw, but ofcourse it runs? Someone else asked me to find them a 3500 poulan also.

Seems it is hard to find a MAC parts saw. The only ones I could find were disassembled. Ron
 
Can someone remind me on the SDC carbs what the deal is with the pump diaphragms? It had gasket, teflon, then rubber diaphragm in that order. The teflon diaphragm only has the valve leaves, not the actual diaphragm part if that makes sense. The black rubber one is complete. How should this go together?
ab673cbb700282e70d690ce2fe084e91.jpg


Sent from my SM-G950U using Tapatalk
 
Can someone remind me on the SDC carbs what the deal is with the pump diaphragms? It had gasket, teflon, then rubber diaphragm in that order. The teflon diaphragm only has the valve leaves, not the actual diaphragm part if that makes sense. The black rubber one is complete. How should this go together?
ab673cbb700282e70d690ce2fe084e91.jpg


Sent from my SM-G950U using Tapatalk
Can you see the manual page?
 
Yes I can, I have that manual and it shows both diaphragms numbers 24 and 25 but it doesnt specify when or if they a re both needed. I know I've assembled a ton of SDC carbs with only one. And I think I remember the pump cover dictating thick or thin gasket.

Sent from my SM-G950U using Tapatalk
 
Some of the SDC carbs that I've rebuilt require both diaphragms (black & tan),while others only require the black one.When I pull a carb apart I make sure I'm paying attention as to how many diaphragms are in the carb,especially if it came out of a running saw.When I first started rebuilding carbs I was nervous as all hell,but now it's like 2nd nature.That dang metering spring still gets to me though.I can't tell you how many of those I've lost.Lol
 

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