MCCULLOCH The official McCulloch thread

[Steve]

Is it a mcculloch branded drum by chance? Typically I have found the mcculloch stamp have the small spline and the Oregon ones have the large spline. It's not the rule but just an observation of mine.

 

[the 28inch mac man]

Is it a mcculloch branded drum by chance? Typically I have found the mcculloch stamp have the small spline and the Oregon ones have the large spline. It's not the rule but just an observation of mine.

I'll have to check.

 

[heimannm]

McCulloch small spline drum to fit the 10/600 Series saws is 86948, Oregon PN 18459.

McCulloch large spline drum to fit the 10/600 Series saws is 86947.

I don't know of any small spline 3/8-8T but large spline 3/8-8T are readily available. I have a bunch...

Mark

 

[the 28inch mac man]

McCulloch small spline drum to fit the 10/600 Series saws is 86948, Oregon PN 18459.

McCulloch large spline drum to fit the 10/600 Series saws is 86947.

I don't know of any small spline 3/8-8T but large spline 3/8-8T are readily available. I have a bunch...

Mark

Thanks Mark, I'll get a different drum.

 

[Dream]

McCulloch small spline drum to fit the 10/600 Series saws is 86948, Oregon PN 18459.

McCulloch large spline drum to fit the 10/600 Series saws is 86947.

I don't know of any small spline 3/8-8T but large spline 3/8-8T are readily available. I have a bunch...

Mark

Speaking of drums and rim sprockets, im finally getting the SP81 back together.
Last night i looked over the sprocket and decided it was VERY worn out. Then i realized that it was a .404" sprocket. The bar and chain on the saw WAS NOT.
Guess that explains the wear.
Whoever had this ole girl before was just making stuff work i guess.
Its got a very low hour 3/8" x 7 pin sprocket on now.
Im assuming small spline, as the donor sprocket came from a PM55 carcass.
Here are some rough measurements if it helps anyone.
Last one is an APPROXIMATE ID. Hard to get an accurate measurement.

 

[Dream]

So heres a "during" pic or two of the SP81.
Got it put together and started. Ran ok, but i had to give it one quick prime with mix to get it to pull fuel. I replaced the fuel cap duckbill valve(after i broke the original, oops).
Gonna go ahead and clean the carb and put in a kit. Just doesnt run quite right yet. Tune is wandering a little. Noticed the carb gasket looks pretty flattened out, and there seemed to be a little fuel under it when i pulled the carb. That will get replaced as well.

 

[Dream]

Yep, carb is pretty bad.
That was dumb of me to try to run it like that, but i thought it was cool that it started and ran after sitting since the mid-1980s.
It will get a soak in carb cleaner, then a spa treatment in the ultrasonic.

 

[heimannm]

Note that Walbro recommends the thick gasket on the fuel pump side with the stamped steel cover and the thinner gasket when used with the cast aluminum cover.

Mark

 

[Dream]

Note that Walbro recommends the thick gasket on the fuel pump side with the stamped steel cover and the thinner gasket when used with the cast aluminum cover.

Mark

Thank you sir.
I was about to go back and find that info from last week. Saved me a trip.

 

[edju1958]

By the looks of that fuel pump diaphragm,I'm surprised the saw ran at all.You probably could use the metering diaphragm as a frisbee,Lol.

 

[the 28inch mac man]

So heres a "during" pic or two of the SP81.
Got it put together and started. Ran ok, but i had to give it one quick prime with mix to get it to pull fuel. I replaced the fuel cap duckbill valve(after i broke the original, oops).
Gonna go ahead and clean the carb and put in a kit. Just doesnt run quite right yet. Tune is wandering a little. Noticed the carb gasket looks pretty flattened out, and there seemed to be a little fuel under it when i pulled the carb. That will get replaced as well.
View attachment 433161View attachment 433162

Nice job! That sp 81 is looking great.

 

[the 28inch mac man]

You guys should checkout the parts that "max the mac man" has just posted on ebay. He has some real nice nos sp 125 parts for sale.

 

[Gvsu141]

Just scored this pretty clean PM650 for $60 on the way down to Ohio for work. I have a friend that's been wanting one for a few years, so I had to grab it just to rub it in his face

I'm sure it will need a carb kit and the usual...

 

[the 28inch mac man]

Just scored this pretty clean PM650 for $60 on the way down to Ohio for work. I have a friend that's been wanting one for a few years, so I had to grab it just to rub it in his face

I'm sure it will need a carb kit and the usual...


View attachment 433521
View attachment 433522
View attachment 433523
View attachment 433524

Nice looking saw! I'm shore your friend will love it.

 

[hacskaroly]

Just scored this pretty clean PM650 for $60 on the way down to Ohio for work.

Nice looking saw!

I was just thinking the same thing!! Congrats on the saw!!

 

[Dream]

Looking for a little advice. Got the SP81 back together. Think its burning a little bar oil, but nothing serious.
Just cleaned the carb. 2 hours in NAPA brand carb cleaner, then 30 minutes in the ultrasonic with water temp about 40C/110°F.
New carb kit.
Metering lever is level with housing.
Tab is hooked in metering lever.
Black gasket to pump side, then teflon.
Thick gasket used with stamped steel cover.
Fixed hi jet carb.
Saw idles and accellerates fine.
Wont open up in the cut. Bogs if you dog in at all. Stalls the chain. Seems WAY too rich.
Blew through a tank of fuel.
Seemed to open up as it was running out of fuel.
Anything i can do to fix?

 

[Woodslasher]

Stupid question and highly unlikely, but did you see if the decomp got pushed in? I had a "low power, running funny" issue with one of my SP81's, turns out the decomp got pushed in during a cut (and the compression wasn't pushing it out) and the saw was still running, just not right. Otherwise, someone did this on my SP81 carb that had a fixed jet and it ran flawlessly, maybe it was to fix a similar issue?

Put together my SP81 and rebuilt the carb, somebody did some mods in the past so I'll be curious to see how it runs.
View attachment 390602View attachment 390603View attachment 390604View attachment 390605View attachment 390606

 

[Dream]

Stupid question and highly unlikely, but did you see if the decomp got pushed in? I had a "low power, running funny" issue with one of my SP81's, turns out the decomp got pushed in during a cut (and the compression wasn't pushing it out) and the saw was still running, just not right. Otherwise, someone did this on my SP81 carb that had a fixed jet and it ran flawlessly, maybe it was to fix a similar issue?

Pretty sure the decomp is sealing. This thing has almost 200 psi compression. If it closes, you arent pulling that rope. Found out the hard way a couple of times. It closes if the saw even thinks about firing a charge.
Plus, its done this since i have had it, i just wasnt aware it was a separate thing, as tje saw also needed crank seals.
As far as that mod, i would think that might allow more fuel in. I need less.

 

[Dream]

So i have an SDC44A from a PM700.
Has anyone tried one on an SP81?
Has the same venturi size.
I have modified the ends of the jet needles so i can sneak in and tune it. Currently being cleaned.
When i took it apart i noticed it only had the black diaphragm. Thin gasket, as its a cast cover.
Do i need the teflon diaphragm and the black one?

 

[Steve]

Black diaphragm will pump the most fuel

Teflon will pump less

The lexan ones (blue plastic) like in some of the wt carbs pump the least.


Check to make sure your meeting needle seals and passes a pressure test. Lastly, if the high speed check valve is bad it will dump fuel as well.