McCulloch Chain Saws

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MOST have two 1/4-20 threaded holes. Use gear/steering wheel puller.

I have one like this:

81x91lj1qEL._SY355_.jpg


I assume what I really need is one like this?

41780.jpg


I do also have a slide hammer kit that may have a puller adapter...

I will try the dead-blow hammer trick first though.

What is the torque spec for the nut holding the flywheel on?


Rob
 
I answered my own question about flywheel nut torque. I remembered I had a service manual and that states 240-300 in-lbs.

Rob
 
If you go the dead blow route, have the flywheel nut threaded on just to the end of the crank, grab a fin on the counterweight side with vise-grips (to hold the saw up in the air) and give the nut a couple good whacks. Should pop loose fairly easily. If not, a few taps around the outside circumference (not top) of the flywheel may help it along. I've popped many flywheels this way and haven't damaged one yet. I have almost ruined a crank by not having the nut threaded on far enough once and hit it with a glancing blow hard enough to skew it down the threads and bugger em up pretty good. Was fortunate enough to be able to clean em up on that one.
 
As Poge and Joey stated, it shouldn't take a lot of force to get it off. The second type you pictured is good, usually not enough clearance to use a jaw type puller.
 
The 10 Series don't have the threaded holes for a puller like the large frame saw do. I use a two jaw puller on 10 Series saws if they don't pop off with a couple of taps on the end of the crankshaft. As noted, make sure you have the nut threaded on flush with the end of the crankshaft before you give it a wrap. The flywheel is small enough that I can hold the saw up by the flywheel when I strike it.

My guess would be low compression on the PM800. Hopefully it is just a stuck ring and you can get them freed up and replaced.

Mark
 
The 10 Series don't have the threaded holes for a puller like the large frame saw do. I use a two jaw puller on 10 Series saws if they don't pop off with a couple of taps on the end of the crankshaft. As noted, make sure you have the nut threaded on flush with the end of the crankshaft before you give it a wrap. The flywheel is small enough that I can hold the saw up by the flywheel when I strike it.

My guess would be low compression on the PM800. Hopefully it is just a stuck ring and you can get them freed up and replaced.

Mark

Thanks for the tips.

I tried to do a compression test on it yesterday but the tester my buddy had didn't seem to have the exact right end on it. It was threaded right, but just too long compared to the plug thread length. Tried to screw it in until seated but it went in to far. First pull the piston immediately hit the bottom of the tester (was right as I started pulling the rope so it didn't have much momentum). Put a nick in the top of the piston but didn't put a hole in it. Ugh. Ultimately after backing the tester out I was able to get a reading of just under 90, but I'm not confident of it because of the previously mentioned inability to seat the tester. The saw definitely doesn't feel as stout when pulling over as my other saws though.

How would one check for a stuck ring?

Thanks,
Rob
 
Will the Oregon bar off my super XL fit my pro Mac 700? Takes the same chain which doesn't mean squat! Homelite will be down for a bit.
 
Will the Oregon bar off my super XL fit my pro Mac 700? Takes the same chain which doesn't mean squat! Homelite will be down for a bit.

If it's a D096 mount it should. You will need to make some spacers to bring your bar studs up to 3/8" dia. if it has 5/16" studs. I use 3 or 4 coils cut off a 3/8" expansion spring from the hardware store or an "S" clip which are getting hard to find. Those bars have an opening from the adjuster holes to the chain groove (as well as the regular oil hole) and that where the MAC will pull the oil from.

If it's a D176 mount and the saw has 5/16" bar studs it will bolt right up

"S" clip

S clip.jpg

D096.gif
 
Looks like I found the issue with the PM 800. The exhaust side of the piston has a pretty big chunk out of the leading edge lined up with the port. And there is additional gouging/scoring on the side in the same area. Also, I can't seem to see the rings. I see two groves in the piston but there doesn't seem to be anything in them. Not sure what that means??

20170918_173047-L.jpg

20170918_173204-XL.jpg

20170918_173140-L.jpg


So, I assume this means the saw is only recoverable with a new piston and cylinder? And I assume that is cost prohibitive? Any other reasonable options to make this thing work?

Thanks,
Rob
 
Thanks. So is there anything difficult about taking it apart or steps that are important to do so I don't wreck it further? This is the type of new project I find enjoyable to tackle but I don't want to make a stupid mistake and destroy it.

Is it best to search for a piston by the exact part number on eBay or via a more generic "McCulloch 800" or something?

Thanks,
Rob
 
The IPL lists three possible pistons. Will I be able to find out specifically which I need after I take it apart by looking at some specific characteristic of the current piston or by a part number on it?

92518 Piston Assembly "A"
92519 Piston Assembly "B"
92520 Piston Assembly "C"
 
Eccentric said:
Yep, but you MUST match the piston to the cylinder. Look for a letter stamped on the head near the comp release bore. "A" matches the 92518 piston. "B" (or no letter stamp) matches the 92519 piston. "C" matches 92520. The pistons will usually have the letter ink stamped onto the crown.

Answering my own question. Found this in another old post that will guide me.

Is it odd that my PM800 doesn't have a compression release? Or is it just in a different location than I'm used to on the smaller 10-10s and 700s?

Rob
 
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