Interesting I wonder what else they changed cylinder wise with the 8200. Other than the obvious stuff I mean.
I also wonder how a Qport saw runs with the Q welded in and a replate. Be interesting to compare the port numbers
McCulloch Chain Saws
- Thread starter Bruce Hopf
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Interesting I wonder what else they changed cylinder wise with the 8200. Other than the obvious stuff I mean.
I also wonder how a Qport saw runs with the Q welded in and a replate. Be interesting to compare the port numbers
Well that giant muffler presents a few problems for me as far design goes , but the heat is the biggest problem.
It runs the length of the engine which would literally heat the entire saw ,and being that heat is an engine's worst enemy its bad.
Air fuel ratio's change with ambient air temperatures for a little 2 stroke because of seasonal changes, (cold air is denser and can bond with more fuel for combustion) ,now factor in the huge muffler generating that large of a hot zone and it would actually hurt performance of the engine .
It runs the length of the engine which would literally heat the entire saw ,and being that heat is an engine's worst enemy its bad.
Air fuel ratio's change with ambient air temperatures for a little 2 stroke because of seasonal changes, (cold air is denser and can bond with more fuel for combustion) ,now factor in the huge muffler generating that large of a hot zone and it would actually hurt performance of the engine .
Ya know I never even thought about the heat thing
Sure , I remember most of the early catalytic converters that were installed on American vehicles in the late 70s and 80s . They were equipped with "grass shields" to keep people from catching tall grass on fire when they pulled of the pavement. They got hot because they were a restriction in the exhaust system and heat just built up against the restriction, but the heat and restriction also affected the entire engine performance. Vapor lock can occur even at idle because of the dissipation/evaporation of fuel and the thin amount of air particles if the engine is hot enough.
The AV system on the saw probably helps alot by isolating the fuel tank and carburetor but there is a sweet spot/temp that you want to have the saw running at, too cold and fuel will puddle and not atomize to mix with the air, to hot and it vaporizes off most of the higher octane components and is a less dense charge.
LOL Remember Dad in his backyard in late 80's,his 78 Merc Grand Marquis with the 460,Holley 4 barrel had that cat convertor plugged,engine ran sluggish.Unhooked tailpipe from back end of converter.Took an old wore out 18" long 3/4" diameter ship auger,chucked it in 1/2" drill,bored a few holes in that thing,hooked it back up.Stomped on gas pedal a few times,there was a big boom & whole backyard filled with smoke 
Sure wish I got some pics,didn't have a videocamera or anything like that unfortunately.But I do remember it running strong with quick response for the next few months until it hit a unseen stout parking bumper at night in the rain going almost 40 across a huge parking lot as a shortcut....Bent that heavy front frame underneath,insurance company totaled it out after that.
Sure wish I got some pics,didn't have a videocamera or anything like that unfortunately.But I do remember it running strong with quick response for the next few months until it hit a unseen stout parking bumper at night in the rain going almost 40 across a huge parking lot as a shortcut....Bent that heavy front frame underneath,insurance company totaled it out after that.
Muffler modded the old Mercury you say.
Mark
Mark
Well a day after getting the 81 running I thoroughly tested it out tonight. Hauled off 2 trailer dump loads of mostly oak with some maple mixed in. Saw ran quite well, but I feel like it's leaving a little on the table up top. I don't know if it's that #31 hi jet that's a little rich or if the fixed jet carb just holds it back a bit. I've got a sdc 38 from my sp80 parts saw I might try on it. You guys think it'll run better?
I also ran my 10-10s in the pile with a 16" bar. Thing runs like a scalded cat. What an awesome little saw. I think throwing an 18" bar on it will be perfect.
I also ran my 10-10s in the pile with a 16" bar. Thing runs like a scalded cat. What an awesome little saw. I think throwing an 18" bar on it will be perfect.
FINALLY got my Super 250 running... It's a feebay buy that seems to be in very good condition, but man did it fight me every step of the way... Have yet to cut with it, and it only came with an 18" bar - trying to decide whether to not to keep it .404, but excited to try it out. Loud and heavy. NOT sad about it. 
Surprised to hear people don't like the 1000, I basically stole a Partner 440 not long ago off ebay (earlier version of the same saw) that's a beast...
Powermac 320 question for ya'll:
Any quirky things I should know about these? I've got one I've been working on, and it starts and mostly idles, WOT seems good, doesn't seem to be abused, but man is idle erratic. Carb rebuilt, impulse line replaced, new carb boot... High needle seems happy at 3/4 to 1 turn out, but low I can back out like 3 full turns and it's still happy, which is excessive. Thinking the needle lever might need to be a little higher? I can't tweak that much though as then high will be too rich to tune. I sprayed around both ends of the carb boot while it was idling, but no change, so that's not leaking... Could be crank seals, but not tryin' to go that deep on this (yet anyway).
Kinda feel like this post from Cliff R:
https://www.arboristsite.com/community/threads/mcculloch-320-powermac-help.104976/
Surprised to hear people don't like the 1000, I basically stole a Partner 440 not long ago off ebay (earlier version of the same saw) that's a beast...
Powermac 320 question for ya'll:
Any quirky things I should know about these? I've got one I've been working on, and it starts and mostly idles, WOT seems good, doesn't seem to be abused, but man is idle erratic. Carb rebuilt, impulse line replaced, new carb boot... High needle seems happy at 3/4 to 1 turn out, but low I can back out like 3 full turns and it's still happy, which is excessive. Thinking the needle lever might need to be a little higher? I can't tweak that much though as then high will be too rich to tune. I sprayed around both ends of the carb boot while it was idling, but no change, so that's not leaking... Could be crank seals, but not tryin' to go that deep on this (yet anyway).
Kinda feel like this post from Cliff R:
https://www.arboristsite.com/community/threads/mcculloch-320-powermac-help.104976/
joeymt33
I bleed YELLOW!
One of these days I will get it off the shelf and try it out. It’s not very fast but it pulls like crazy.
emf123
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They can be very quirky. The choke can lever rattle up and basically kill it. The throttle linkage can get bound and not want to return to idle. Crank seals on the small saws is a common thing unfortunately. Too much or too little chain tension. I've seen it all. I've got more than I could ever want and use none of them.
I'm finding out how true it is about the crank seals going bad on the plastic Macs.I've got a 3216 & a E.B.2016 that both have bad crank seals.At $10 per seal it's not worth the aggravation of replacing them IMHO.
I don't plan on keeping it, but I don't want to sell it just to have it end up at the dump because it idles funky. Otherwise it seems to be in great condition, and WOT has plenty of power (for this size). If I don't make any progress I'll either shelve it for a future project or donate it to the Mac Museum
Funny you say that about small saws - I know people hate the 110's (minimac, whatever) but I love them because despite having to disassemble them to work on them, they just run. Like, forever. Just finished rebuilding a handful of old, small Homelites and Poulans that idle and run great too and they mostly just needed carb cleaning and fuel lines. The XL's/Super 2's are kinda in the same boat as the mini's; have to pull the whole engine out of the housing. One pitfall that gets me sometimes though is the smaller displacement saws are (understandably) MUCH more sensitive to carb tunes/tweaks/changes.
10-10s update... After everything turns out it was the walbro carb. Rebuilt another one I had off a parts saw, swapped it out. No fuel leaks in carb box. No fuel dumping into cylinder. Cranked, adjusted, and ran fine. gonna pull the kit out of the faulty carb and save the parts. This was a first for me. You experts reckon the body of the carb is cracked somewhere, somehow?
Max
Max
Aaron Rybicki
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Maybe a 47 or 3-25? A Mac 77 should fit.
I always take out the starter paws and thread the bolts/screws for my puller in them put a fair amount of tension on it and tap the end of the puller with a small hammer, also spray alittle Deep Creep on the crank also.
As long as you have the screws bottomed out and aren't using them to really reef on the puller the flywheel usually pops off.
The 38 is a good carb. I'd swap it out.
Thanks for the input, definitely thinking I'll swap it out this weekend.
Maybe the seat is just buggered up and the needle can't seal?
I had a Homelite 240 that I almost just dropped a match in the gas tank and walked away from because it would do this. Turns out there was just some funk floating around that would randomly end up in the needle seat. It would be fine for days, then one day flood, leak gas out the muffler, etc. If I had an nickel for every time I had it apart, I could retire. Same fiasco with a 10-10 carb that had a loose welch plug. Everything looked good when I took it apart, and then finally one day the plug literally fell out. Must've been the factory sealant around the edges holding it in, but it never felt loose on inspection. That 240 starts and runs flawlessly now and I've actually come to like it quite a bit.
Anyway, might try checking down the needle hole with a loupe, or magnifying glass, or take a picture with your phone (+flash) and see what it looks like? You can zoom in pretty well with a digital pic if you can get a good light down there and get it to focus. FWIW, I got a cheap set of plastic loupes of different magnifications on Amazon and REALLY like them for this kind of stuff.
Have you been able to test pressure on it? I just use a piece of (new) fuel line and see if it'll stick to my tongue if I put a vacuum on it, or hold pressure if I try to blow air through it. You can usually hear it hiss if it's leaking, or put a few drops of wd-40 down there and see if it'll bubble. Gotta get a mityvac one of these days...
-Rich
