McCulloch Chain Saws

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Not sure if Walter did anything but for a Large Husky mount (D009) I just opened the chain tension adjust holes in the bar upwards until they were into the chain groove / slot in the bar. Pretty much making the adjust hole like they are in a D176 mount which needs no mods for the 10 series.

Saved for Later.
 
Does anyone have information on setting the carb diaphragm height on the 3-25? I finally got mine running today but floods out quickly. I was running it without the tank installed and used a bottle to feed gas to the bowl and it was fine but I wasn't keeping constant pressure on the bottle. I have triple checked the check ball and seat and they look good - don't know what else could make it flood. Also looking for initial setting for the H needle. I was using 1 turn out like other saws.
The proper setting is to pull up on the metal disc in the center of the diaphragm until full travel is reached. Look across the upper edge of the chamber and the lower edge of the metal should be flush with edge of chamber. You can bend the hook assembly to get the proper setting.

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The proper setting is to pull up on the metal disc in the center of the diaphragm until full travel is reached. Look across the upper edge of the chamber and the lower edge of the metal should be flush with edge of chamber. You can bend the hook assembly to get the proper setting.

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MANY THANKS!!!
 
The proper setting is to pull up on the metal disc in the center of the diaphragm until full travel is reached. Look across the upper edge of the chamber and the lower edge of the metal should be flush with edge of chamber. You can bend the hook assembly to get the proper setting.

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I had already lowered it some but it was still a tad too high. All back together now - will find out tomorrow morning.
 
A Mac 250 was left this afternoon at the front of the shop (odd, but we have people leave saws and mowers from time to time. Sometimes I'm pretty sure it's just because they didn't want to pay to throw it out).

Anyhow, something someone could use? Has a 18ish" bar, and looks to be at least .404 chain. Not sure if it could run, I didn't even try to pull it over. (I can check tomorrow)
 
A Mac 250 was left this afternoon at the front of the shop (odd, but we have people leave saws and mowers from time to time. Sometimes I'm pretty sure it's just because they didn't want to pay to throw it out).

Anyhow, something someone could use? Has a 18ish" bar, and looks to be at least .404 chain. Not sure if it could run, I didn't even try to pull it over. (I can check tomorrow)

250 or 250 Super?
 
The only wood cut by me today was a hammer handle and an axe handle. I was on granddaddy duty. Rumor is Brian was at the wood lot this morning bucking some 3'+ stubs. Hopefully with his PM800 and not his Chinacom 660. Maybe he will report.

Posting a picture of the small ball peen just in case Eccentric checks this thread. I picked the hammer up off the ground at my dad's old house. Needed a handle and lots of rust removed. Was surprised to find an International Harvester imprint under all of the rust. Not sure if you can see it in the picture or not.

Ron

IMG_2723.JPG
 
Don't know. Left side has the logo stamp with "INTERNATIONAL" stamped underneath. Front has "8" cast/forged at top and "M" in a circle at bottom. Right side stamped "999 522 A" with "U.S.A." underneath. Back side "8" cast/forged at top and "T8" at bottom.

I can tell by the handle repair that it likely was something my dad picked up at a yard sale.

Ron
 
I had already lowered it some but it was still a tad too high. All back together now - will find out tomorrow morning.
Still no good. As long as I shut the valve off to control the flow, it runs fine. This is the first carb I've seen that doesn't have a spring to keep the inlet closed - I don't see one in the ipl. Maybe the replacement diaphragm I got is too flimsy?
 
The 77 IPL does not show a spring either, but someone before me had added on in that carburetor. They tried to solder in in place but the solder did not adhere to the spring; none the less the solder on the lever arm worked to hold the spring in place. You may find it necessary to McGyver a spring on yours as well.

You can see the solder on the arm in this photo.

DSCN4765.JPG

Mark
 
Thanks Mike - I may resort to that. I got hold of a service ipl for the 4-30. A little different that the 3-25 but close. On the 4-30, the idle mixture screw is actually an air bypass, not fuel control. Screwing it clockwise makes it richer. I had been screwing it in clockwise and out 1 turn like later carbs. Is it the same on the 3-25? If so, I've been making it richer, not leaner by screwing it in. Will try again tomorrow. The only other thing I can think of is if I have the small metal plate that fits between the two gaskets where the carb mounts to the block. There is an extremely small hole that I think is for the idle mixture. If reversed, it might cause excess fuel.
 
Thanks Mike - I may resort to that. I got hold of a service ipl for the 4-30. A little different that the 3-25 but close. On the 4-30, the idle mixture screw is actually an air bypass, not fuel control. Screwing it clockwise makes it richer. I had been screwing it in clockwise and out 1 turn like later carbs. Is it the same on the 3-25? If so, I've been making it richer, not leaner by screwing it in. Will try again tomorrow. The only other thing I can think of is if I have the small metal plate that fits between the two gaskets where the carb mounts to the block. There is an extremely small hole that I think is for the idle mixture. If reversed, it might cause excess fuel.
Never mind the question on the idle mixture screw - it is the same on the 3-25.
 
Still no good. As long as I shut the valve off to control the flow, it runs fine. This is the first carb I've seen that doesn't have a spring to keep the inlet closed - I don't see one in the ipl. Maybe the replacement diaphragm I got is too flimsy?
These carbs don't work under spring pressure but the fuel itself. The fuel fills the carb chamber from the fuel pump under the tank operated by crankcase pulsations and rises against the diaphragm which raises the arm and ball assembly closing off the flow of fuel.

The idle is mixed with air from the top half of the carb chamber with fuel and is drawn from the bottom half up through another tiny hole into the housing through the throttle gate and into the venturi through the rotary valve into the crankcase. Much unlike your more modern saws. I'd recheck your Lowe half to make sure the arm and ball are seating OK with no debris keeping the fuel from shutting off.

Nick


The mixture screw on these is air only and in is less air, more fuel. The lever adds more fuel into it for high speed operation.

Actually the high speed adjustment or fuel adjustment must be made before the air adjustment screw is adjusted. The proper amount of fuel is set with the lever to run smooth and then the idle air screw is adjusted. It's an entirely different machine

So if your getting too much fuel the lever has to be leaned out to reduce fuel. You have to lift up and pull back to adjust it with its ratchet mechanism and set it back down then move it again. It's a process...



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