McCulloch Chain Saws

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Good job Mark as always:)

Tinman took to that 850 with a burr. Will see what she runs like. He showed every little bit nicely and think will be rather easy to have a go at with his video playing in the shed.



My 81 is getting due for a rebuild so I might attack it and maybe the muffler too. Perhaps even just blanking off the "box" and letting it vent straight out.

Only thing is I don't want to ruin that low down pull the 82s have

Alot of what I see in his video is what Bellhopper does with the 10-10 , but I think he doesn't realize how huge of a difference those exhaust and intake numbers change with the tiny grinds. Raising the intake has the sole purpose of rpms and loosing torque which isn't a good thing in my opinion.
He really took alot out of that exhaust whether he knows it or not .
After witnessing the 288 vs 394 debacle on buckin's channel I'm hard pressed to believe any results from porting this saw has.
The chrome on these cylinders can be compromised around that exhaust port and I wouldn't gamble with grinding the edge of it to peel.
I know Mac131 is going to be putting together an 850 in the next few weeks and I'd wait to see what he does , his intentions are saws and his integrity looks to have the right compass setting .
 
Finally, Back to my McCulloch Super 797 Seized Piston issue. As per recommendations, I filled up the plug hole with Marvel Mystery Oil and have let it sit. I also removed the muffler and sprayed in some PBlaster. It has been a couple days soak time (ya, I know…I lack patience)…but tonight I unbolted the carburetor and seen if there was anyway to inject Marvelous Mystery Oil in there….it didn’t look that way. Strangely enough, it looked like I was peering into the intake hole only to be looking at the back wall of the fuel tank? I really could t see what path the fuel charge follows?
Question: Would it be helpful to just point my PBlaster Nozzle Tube down into the intake cavity and fill it up? Or should I just continue to wait…Thoughts ?
Go to the "beg for manuals " thread and do yourself a favor.
 
Removing clutches & replacing them on 610s is a piece of cake,I've done it many times.2 yrs.ago I replaced a clutch 3 times on a 610 thinking the drum was worn out because when I fired up the saw the clutch area would smoke from heating up.Come to find out I wasn't getting the chain seated properly on the rim,it was going between the rim & the drum.(some of the clutch drums have removable rims & others are fixed onto the drum).After the 3rd clutch drum "being bad" I thought something must be awry.I felt really stupid when I discovered what was happening.
 
Alot of what I see in his video is what Bellhopper does with the 10-10 , but I think he doesn't realize how huge of a difference those exhaust and intake numbers change with the tiny grinds. Raising the intake has the sole purpose of rpms and loosing torque which isn't a good thing in my opinion.
He really took alot out of that exhaust whether he knows it or not .
After witnessing the 288 vs 394 debacle on buckin's channel I'm hard pressed to believe any results from porting this saw has.
The chrome on these cylinders can be compromised around that exhaust port and I wouldn't gamble with grinding the edge of it to peel.
I know Mac131 is going to be putting together an 850 in the next few weeks and I'd wait to see what he does , his intentions are saws and his integrity looks to have the right compass setting .

I had better watch the video then.
Edit.. so what went down on Facebook??

The chrome edge thing does indeed worry me and definitely want to see how it runs before I even consider it. Definitely do not want to kill the torque that's the awesomeness of those bigger Mac's
 
Any thoughts? Probably best to replace both seals right?

Those seals are cheap and should be replaced if you already have the bottom pan off. What you see on the edge of the seal is the pinch where the two halves of the engine meet.

Any tips or suggestions?

You'll get more responses to Stihl questions in the general forum or Stihl thread (or by simply searching 'Stihl 029 oil seals') than you will in a thread dedicated to McCullochs.
 
Those seals are cheap and should be replaced if you already have the bottom pan off. What you see on the edge of the seal is the pinch where the two halves of the engine meet.



You'll get more responses to Stihl questions in the general forum or Stihl thread (or by simply searching 'Stihl 029 oil seals') than you will in a thread dedicated to McCullochs.
Thank you, I did some more research and came to the same conclusion. Looks like Stihl has (2) types of seals (Soft and Hard) depending on if I remove the pan or not (which I already am just about there)…so I will go with the latter set.
As far as posting in the wrong place, my apologies. I am still trying to figure out how to maneuver my way through forums and stumble all over the place in doing so.,,,,,,,,
 
Just the way I found it Poge...

I finished putting the 5-49 back together today. I think a fellow needs a little practice on these to remember the proper sequence so you don't have to back up and start over so often.

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It does run on a prime but the metering diaphragm is so hard there is no chance of it running on its own. I hope to have someone work on some diaphragms for the two man saws once I get a few other projects buttoned up.

Mark
 
the metering diaphragm is so hard there is no chance of it running on its own. I hope to have someone work on some diaphragms for the two man saws
I'm sure you've investigated some of the home-brew remedies for softening aged rubber and diaphragm material. I personally had good success softening a rock hard NLA XL-2 oil pump diaphragm using the 50/50 brake fluid and acetone formula -- basically as an experiment. It took over a week and a little flexing daily, but it softened considerably -- to the extent required to effectively function again. Pretty much a 'day and night' result. This was late winter. I spoke with the saw owner last week and he indicated it is still oiling quite well, which I suppose is a testament to at least some degree of longevity to the particular approach.

The other popular formula, particularly for rubber, is methyl salicylate (wintergreen oil) and alcohol. Various ratios yield varying degrees of effectiveness, but this particular mixture provides the most effective home brew restoration out there by most accounts. Heating the mixture also seems to have an accelerated result.
The biggest drawback to this approach seems to be the cost of the wintergreen oil itself. That said, if you're just trying to revive a chainsaw carburetor or oil pump diaphragm instead of a motorcycle intake manifold, the cost would obviously be a bit more reasonable. The solution could also probably be re-used for smaller jobs depending on the degree of contamination experienced from exposure to the previous material/part. But like a carb in a smaller container full of SeaFoam in a USC, the same method could obviously be applied to diaphragms and small rubber parts to mitigate the cost -- with, or without a USC.

This is probably the most thorough video I've seen so far comparing the various approaches to softening rubber, though it would be reasonable to assume it could also be applied to other materials hardened by age and/or exposure to petroleum derivatives. At minimum, it dispels several myths about the effectiveness of certain methods. At best, it may be useful information to a roll your own softening process vs. experimenting with the various commercial products and their associated costs. It will certainly be the method I'll try the next time I'm faced with the need to soften a small rubber part or diaphragm.

 

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