McCulloch Chain Saws

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So I just got my spare 81 running and waiting for a new decomp valve to arrive... though what the heck am I supposed to use to remove the old one as I've never removed one before and it's kinda going to need a good wd40ing

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Was gonna respond to this the other day and got sidetracked. And since no one else has, a 7/16 deep well socket is what you'll need. There should also be a washer between the valve and the cylinder that may or may not come off (or be obvious) as you remove the valve. It's listed as a separate part# from the valve and may or may not be included with the new one. Never bought a new one before so really don't know one way or the other. I do use a bit of sealant (DirkoHT) on the threads and washer when I install decomp valves since I've found many that tend to leak there even though the valve itself may not. Any good hi-temp sealant will work.
 
Around 200.00 here.

Brian[/QUOTE

Quite a bit cheaper really.
Hey poge is that the same valve on the 700? Mine doesn't work and figured its full of carbon so I'll need to get it working when it gets a rebuild. Whats the method when it comes to sealing the case halves? I worry about oozing inside.
 
SP81 decomp is listed as 87866 while the PM700 is listed as 94273. Only difference I could imagine may be the length or perhaps the color of the cap on the end. Mark will probably know those details.

Seal the short block like it looks like you should. Only takes a little bead or thin layer to seal these things as they are machined to such close tolerances in the first place. I know that Mac got a bit sloppy with their own sealing method toward the end of their professional production (circa PM8200) and were probably responsible for some of em burning up as a result of the excess coming loose and gumming things up. That's certainly the theory behind my own PM8200 and there are some pics floating around showing the whole mess. I was skeptical at first, then I ran across another guy who posted pics that could have been taken of my saw who had the same exact impregnation of gooey scum on his own piston and cylinder. Just plain ugly.

Use a good sealant like DirkoHT, Threebond 1184, or Motoseal.
 
Ok cheers poge I've got a 10 10 and an the 700 to rebuild still need some more parts yet but nearly ready. Is the decomp absolutely needed on the 700? Just wondering how much compression its missing. It still hangs on the pull cord but definitely dont need a decomp for starting. Its a two pull starting saw even after a couple weeks sitting.
 
So what's the typical top end for a PM800 anyway? McCulloch just says tune for the most power in the cut and not by the sound of the saw. Well, I had mine out the other day in some red oak and wasn't real impressed until I leaned it out a bit more than it was..., which turned it into a whole new saw..., but sounding oh so close to the edge. Haven't put my tach on it yet to see what it's turning but I'm well beyond the typical 'thick' four stroking -- like I mentioned, right on the edge of what I would still consider some burble before I hit the wood. BTW, I'm running 40:1 Stihl Ultra 91 octane e-free with a 24" b/c setup currently fwiw.

I asked Mark this same question a few weeks ago as I’ve had the same exact experience.

I’m running more oil, but I wish there was a number to use to check my ears.
 
This to me is why the 800 muffler is bad. Its alot harder to hear that 4 stroking compaired to any saw ive owned or played with.. not many haha i only have 10 but yea maby ive got toast hearing already but i can never be happy with its tune allways second guessing and end up fattening it up again out of fear

Same Here.

I have to struggle to hear any 4 stroking.
 
I got a call Thursday evening after a big Thunder Storm from my cousin who informed me that the Big Poplar down at the Branch has been struck by lightning, had all kinds of mess hanging in the top, & would I come
Put it on the ground before the broken sections fell out & hit someone.



It was eerie, & the guts were blow. Out of it in addition to it being rotten & hollow.

2157105efb6e4f7ffc21761793e7e025.jpg


The Mac 800 did its job.

I’m glad I had a fresh-sharpened skip chain on it because I would have hated to of not found that barbwire.
 
It may be a different story with new rings. If nothing else, the decomp will extend the life of your starter assembly if you have any kind of decent compression.

Yea the poor old starter has bin pulled on on for 40 years so thats a good point.


I got a call Thursday evening after a big Thunder Storm from my cousin who informed me that the Big Poplar down at the Branch has been struck by lightning, had all kinds of mess hanging in the top, & would I come
Put it on the ground before the broken sections fell out & hit someone.



It was eerie, & the guts were blow. Out of it in addition to it being rotten & hollow.

2157105efb6e4f7ffc21761793e7e025.jpg


The Mac 800 did its job.

I’m glad I had a fresh-sharpened skip chain on it because I would have hated to of not found that barbwire.


Sounds like a you had a fun time hsell does poplar grow ok there? Its very soft no good for burning here it grows to fast. A pine tree is ready for harvest in 25 years here but is also very soft and just "ok" as firewood at 40 years it gets nice n sappy
 
I cannot confirm the veracity of all the following part numbers but this is what I have in the compression release parts bin. It appears that 87866 turned into 94273. They are fine threaded with a long reach and a short cap. Most of the compression release valves were 3/8" fine (24 TPI) threads.

20180722_143555.jpg

Looks like the older ones generally had a red cap, the later ones a black cap. First up, SP60...

20180722_144720.jpg

10-10S

20180722_144655.jpg

I am sure that I bought these as 85148 for use in the SP105/125.

20180722_143720.jpg

I am pretty sure both of these were for use in the 600 Series saws. First up, one side of the bag says 94532 and the other 214304 which I now believe is incorrect. Notice fine threads and short reach.

20180722_143622.jpg

20180722_143608.jpg

The brass collar on the second was used as a spacer since the 600 saws actually needed a shorter reach like the ones above. I guess 214304 really the long reach with a spacer. 214304 is identical dimensionally to 85148 if you eliminate the spacer.

20180722_143643.jpg

I am not sure where this fits in exactly but it looks just like 94532, could be I have that number wrong and 94533 is correct..

20180722_152314.jpg

Lastly, the PM800/805/850 Super/DE80/M8200 saw without the "Q" port used a compression release valve with a short reach and coarse 3/8" (16 TPI) threads.

20180722_143537.jpg

I also have this bag but again I cannot confirm the PN is correct.

20180722_143524.jpg

I have a 3/8" drive deep 7/16" socket that I use to remove and install these. A 1/4" drive deep 7/16" socket will work for the ones with the short cap. McCulloch also made a stamped socket (like the socket end of a scrench) that fit the 7/16" hex on the compression release valves but I apparently put my away in a safe place so I can't find it currently.

Mark
 
Yea the poor old starter has bin pulled on on for 40 years so thats a good point.




Sounds like a you had a fun time hsell does poplar grow ok there? Its very soft no good for burning here it grows to fast. A pine tree is ready for harvest in 25 years here but is also very soft and just "ok" as firewood at 40 years it gets nice n sappy

Poplar is the softest of the Hardwoods in our area: I prefer Yellow Pine for building.

We saw Poplar for lathe, & a few smalls inside, but generally it is substandard to Oak or Yellow Pine.

As far as for firewood, there is an abundance of Oak so no need to burn Pine or Poplar.
 
9133b15c738165047c1a9afe3a57ecdd.jpg

5fa5e0da33918bf2de61e1923c67fd05.jpg

I hit them a good luck & wished them well.

I just don’t see filing down the other 60 teeth just cause those 2 found the barbwire.

The rest of them looks like this:
64ade3a52f2470e362937059d9aca751.jpg

Maybe it will cut.
 
I just put a tach on my PM800.

11,700rpm after it warms up....

It didn’t cut so well around 8,900 the last time a ran it prior to this week so I turned it up.

Now I know where it’s at.
 
Poplar is the softest of the Hardwoods in our area: I prefer Yellow Pine for building.

We saw Poplar for lathe, & a few smalls inside, but generally it is substandard to Oak or Yellow Pine.

As far as for firewood, there is an abundance of Oak so no need to burn Pine or Poplar.

Yea oak is great firewood takes a long time to dry though also get alot of bluegum here and thats 3 year dry time too. When bluegum has been down for a long time its like cutting concrete your lucky to get half a tank and its dull. Its weard to think of poplar as a hardwood its like balsa and thats a hardwood technically too and bluegum is a soft wood as its an evergreen. As for your munted cutters jst drop the rakers down n carry on and be nice to them with the file for the next few sharpenings. Buckin billy had a vid showing a chain with all kinds of length cutters just to prove a point and it cut beautifully thats the beauty of the fop style raker gauge.
 
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