McCulloch Chain Saws

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Jethro,you're gonna have to man up with those points,unless you yank them out & put a chip in it.There's really nothing to it once you've done it a time or two_Of course if the condenser is shot you might not have a choice but to abandon the points.There are condensers on feebay,but at $30 + shipping I'd rather spend less than half on a chip.And with those condensers there's no garuntee that they're any good.
 
Im with you there. Played guitar in my wild and wooly days. Probably lost more hearing to that 100 watt music man amp than all my saws put together!!!!
I've played drums and bass in bands for years, probably why I now have a constant ringing in one ear. My van is pretty noisy too.

@Jethro 2t sniffer if you're getting anything from Mark do you want to combine shipping with my order (when I get around to confirming it)?
Could save you some coin.
 
Jethro,you're gonna have to man up with those points,unless you yank them out & put a chip in it.There's really nothing to it once you've done it a time or two_Of course if the condenser is shot you might not have a choice but to abandon the points.There are condensers on feebay,but at $30 + shipping I'd rather spend less than half on a chip.And with those condensers there's no garuntee that they're any good.

Well I did clean up the points on the 81. Didn't take them out though. Way too scary
 
Working on a 73 for a friend, hope to have it ready for the PNW GTG coming up in a few weeks.

Saw on the left turns over with good compression, saw on the right is locked up...

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...but the saw on the left has some issues with the starter, clutch, and gear box cover...

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Getting things taken apart so I can clean them up and sort out the best pieces.

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Mark
 
I did get the better saw cleaned up...

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Gear case cover cleaned up and ready to go.

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One of the mounts for the fuel tank were broken off the better gear case cover so I McGyvered a mechanical repair seeing how I don't weld aluminum or magnesium.

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I made some progress last night getting it back together, even has spark...

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Mark
 
For those that may be unfamiliar with the old brutes, the fuel pump in in the fuel tank, and there is an impulse tube from the crankcase to the fuel tank that is remincent of the push rod tubes on the flat four Volkswagen and Porche engines.

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The fuel pump on the underside of the fuel tank. That is the port for the impulse tube just below the pump itself.

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The diaphragm is thin brass, and the valves are in the body of the pump. I couldn't get a good photo of the valves as they are buried in the pump and I didn't want to risk damaging anything getting it apart. I was able to probe the flaps and they are still quite flexible.

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I have a few different examples of the valve, all came to me under the same part number.

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The fuel tank is supposed to have a large felt wick, but somehow they were able to remove it from this tank without taking the tank apart, I am not sure how they accomplished that feat.

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The other tank has the wick but the tank and wick are too crusty to consider trying to use them. I opted for a length of tubing connected to the nipple and a large, weighted fuel filter inside the tank.

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Mark
 
Well I did clean up the points on the 81. Didn't take them out though. Way too scary
There's nothing to be afraid of.There are 2 screws that hold the points in place & the stud on the side of the points box.Just loosen the nut on the stud,take the screw out that holds the condenser in the saw & the points will lift right out with a needle nose pliers.You'll need a feeler gauge to reset the gap on the points - somewhere between .018 - .020 in.Most feeler gauges now have the inch & metric settings punched into the blade.Best thing to do is take an old parts saw apart & have a go on it.Once ya take the points out you'll see it's a cake walk.There are many of us here,including myself,who can walk you through the process.Remember the 1st time you rebuilt a carb?
 
There's nothing to be afraid of.There are 2 screws that hold the points in place & the stud on the side of the points box.Just loosen the nut on the stud,take the screw out that holds the condenser in the saw & the points will lift right out with a needle nose pliers.You'll need a feeler gauge to reset the gap on the points - somewhere between .018 - .020 in.Most feeler gauges now have the inch & metric settings punched into the blade.Best thing to do is take an old parts saw apart & have a go on it.Once ya take the points out you'll see it's a cake walk.There are many of us here,including myself,who can walk you through the process.Remember the 1st time you rebuilt a carb?

I'll do it :) the 81 could do with another look. It's a bit cranky to start. Once running it's happy but yeah a dodgy spark at idle speeds when cold

The 2nd SP70 doesn't seem to have spark but I did only have a rope round the fins on flywheel so it may not have been fast enough. Could be the plug too. Top end feels good I think I'll have a go at saving it.

And yes carbs were scary too :)

when I was a young man, we had to replace points on cars, motorcycles and lawnmowers every tune up. you can do it.
Yeah you older guys just grew up with them like any other everyday item
 
Yea , it’s almost 20.00 less per loop than Stihl or Oregon, figure give it a try . Goood to hear you like it,👍
I and others ran two tanks of fuel through the 125 wearing it in big wood at Hopperstock...still biting hard when we were done.
 
I'll do it :) the 81 could do with another look. It's a bit cranky to start. Once running it's happy but yeah a dodgy spark at idle speeds when cold

The 2nd SP70 doesn't seem to have spark but I did only have a rope round the fins on flywheel so it may not have been fast enough. Could be the plug too. Top end feels good I think I'll have a go at saving it.

And yes carbs were scary too :)


Yeah you older guys just grew up with them like any other everyday item
Speed of cranking over a points saw doesn't produce a hotter spark.In fact if you pull the plug out & ground it to the saw you should be able to produce spark while turning the FW by hand.The electronic ignitions require a brisk pull to get a good spark though.
On your SP81,your condenser could be getting weak,but usually it'll start breaking down when your saw gets warm/hot.If it's running at a high idle it could be crank seals.
 

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