stinkbait
Addicted to ArboristSite
I haven't been to Tennessee since last May. Honest.
McCulloch Super Pro 81
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I haven't been to Tennessee since last May. Honest.
Just messing with you. Mine doesn't have a gas cap.
McCulloch claims these put out more ponies than a PM850. Other than the design of the exhaust port I don't know what the internal differences are. I'm hoping a ported SP81 will outperform a stock PM800.
Check for a PM. Ron
stinkbait
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The PM800 does have an odd exhaust port. The is, I guess what you would call, a compression relief machined into the top of the port. I think that it would hurt overall performance. I didn't really like the design the first time I saw it. Why didn't they just put a compression release on there instead of altering the exhaust port. Does yours have the funny exhaust port since it has the compression release? The SP81 does not have that, so I think that it would be capable of higher compression than the PM800. My new SP81 cylinder doesn't have that funny exhaust port either. I will try and get some pics of both so people will know what we are talking about.
That was a very good deal for the SP 81. Was bidding on one this morning on ebay that went for just under $200, plus shipping.
Hal
Hal
From post 33 at http://www.arboristsite.com/chainsaw/150624-3.htm#post2503609 are my pictures of ports.
Ron
stinkbait
Addicted to ArboristSite
From post 33 at http://www.arboristsite.com/chainsaw/150624-3.htm#post2503609 are my pictures of ports.
Ron
Those pics show the ports well. Where did you get that NOS block?
Trouble is, you never know what they will go for on ebay. It might be $15 or $500 depending on when it's on there. I sold 2 almost identical saws, one went for a great price, the other I got nearly nothing out of.I just picked this up on CL. Looks like a real nice saw. I talked with the owner and he said that it runs great and has good compression. I gave $70 for it. I thought that it was a good price, considering what it would have went for on ebay.
My best eBay buy - $9.95. Regular MAC part seller didn't know what it was and listed it as unknown. I ask for bore measurement. Seller responded but didn't change description and no one else bid.
There was a recent one listed as a PM800. Seller said it was too late in the sale to change the description. He said he would advise the high bidder. It sold for $79.99. I believe if it was listed correctly it would have brought more.
Ron
dieselsmoke
ArboristSite Operative
Nice CL grab. I've watched Ebay for a couple of years now, looking for a nice one, they usually bring $200 or more! Most of the ones from the west coast probably spent time in the woods, not a good history for a 30+ year old saw.
I finally found two locally on CL. Was able to test drive, and haggle with the owners, now I'm an owner. SP 80 with aweome comp. and a PM 850, a little long in the tooth, but always runs, and still pulls pretty good. They BOTH need A/V cushions up front. The SP 80 is now my first pick for a firewood saw. Keep the pics coming!!
I finally found two locally on CL. Was able to test drive, and haggle with the owners, now I'm an owner. SP 80 with aweome comp. and a PM 850, a little long in the tooth, but always runs, and still pulls pretty good. They BOTH need A/V cushions up front. The SP 80 is now my first pick for a firewood saw. Keep the pics coming!!
stinkbait
Addicted to ArboristSite
I looked through all my 10 series flywheels tonight and found that I did have one 24 fin flywheel. It's a lot heavier that the 12 fin. I think that I am going to stick with the 12 fin, mostly to keep the weight down.
Duke Thieroff
Fill your hands, you SOB!
All is looking well there Mitch, you should have yourself one heck of a saw there soon.
CT
CT
stinkbait
Addicted to ArboristSite
Well the carb that came on my SP81 is the fixed jet walbro sdc. And that's not gonna cut it for me. So, I have another sdc that is adjustable and that has a much bigger venturi.
Here is a pic of the fixed jet carb that came on the SP81.
Here is a pic of the new adjustable one that I will be using.
Here are some pics of the venturi. There is hardly no taper. It's as big as the sdc that's on my SP125.
I did have to swap out the fuel inlet on the new carb to one like that came on the SP81. It had a plastic inlet in there that wouldn't work with the factory SP81 fuel line.
Here is a pic of the fixed jet carb that came on the SP81.
Here is a pic of the new adjustable one that I will be using.
Here are some pics of the venturi. There is hardly no taper. It's as big as the sdc that's on my SP125.
I did have to swap out the fuel inlet on the new carb to one like that came on the SP81. It had a plastic inlet in there that wouldn't work with the factory SP81 fuel line.
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stinkbait
Addicted to ArboristSite
Headed out to the garage to do some work on the 81. Should make some decent progress today.
I'm curious how you managed to pull the fitting from that carburetor without destroying either, what's the secret?
Mark
Mark
promac850
formerly promac610
+190,482 What is the secret? I've tried to remove one before and broke it... :bang:
little possum
Crash and Burn
Keep up the work Stinkbait! Seen a few Macs yesterday that reminded me of all that yella in them hills 
stinkbait
Addicted to ArboristSite
I used a grease rag and a pair of lineman's pliers. The rag prevents damage to the fitting. Then just give the fitting a little twist back and forth to pull it out.
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Duke Thieroff
Fill your hands, you SOB!
Mitch,
I was contemplating doing that to that carb, but I didn't have the stones to do it, that carb was too new to ruin.
Nice work.
Chris
stinkbait
Addicted to ArboristSite
Yesterday I managed to get some work done on the 81. I removed the crankshaft and connecting rod from the old engine because I will be using them in the newer cylinder. I was able to install the new piston assembly to the connecting rod and remove the old crank seals. I also started decarboning the exhaust port and cleaning up some casting marks to get ready to port it. The only thing that is limiting this saw is that the exhaust skirt on the piston is narrower than the intake. So I don't know how wide I will be able to go on the exhaust yet. I will post some more pis tonight.
