Mcculloch Super Pro 125c Complete rebuild.

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I can see it in my mind's eye. Also am remembering your PM610 experience.....

In my own defense i didnt actually break anything on that saw, i just "flailed" on it for about 2 weeks before i got it running.
Im going to try to read up on all that literature this week while i order and get in replacement parts for this bad boy. In the mean time i have that baileys 390 engine coming in today to put in the 029 super.

Ill try to post a video of the SP125c flywheel today to see if it should be saved.
 
??? whats the play it or delay it thread?

That was a spammer! It's ok to red rep them but don't quote them. The red rep is sort of a flag for the mods and quoting them make clean up that much harder.

When you read a post that makes no sense, like some of yours it's probably a spammer. :msp_scared:
 
I think that was his description of the compression. As in "that thing has so much compression it's retarded".

Randy, are you hiring?

No Tom.......Jon and I have it covered here my friend. We stay busy but I reckon that's a good thing.

Mr. hkusp9

It looks like the key wasn't engaged in the flywheel just right. Take your time and learn to get in a habit of checking things twice........I'm slow at what i do compared to some guys, but I would rather take the time to make sure everything is just so before pulling that rope. Things go south fast at 7000 RPM.........

That tubing you cut of the ignition lead was there to prevent vibrations from rubbing thru and shorting out the lead. What do you plan to replace that with?

You get ready to trade that old Mac for a good running saw give me a call.
 
Randy- we got lots of 125s here on the west coast. So when you're ready for one, give me a holler.

I'll keep that in mind JJ and thanks. I don't really want one, and sure don't need one. I just really hate seeing a classic saw destroyed. Now that's not a *** at the OP or anything like that........It's cool seeing someone being bitten by the CAD bug. I would love to see him slow down and take the time to do this properly rather than keep trying to run the saw before it's really ready to run.......reminds me of me when I was 12. :laugh:
 
No Tom.......Jon and I have it covered here my friend. We stay busy but I reckon that's a good thing.

Mr. hkusp9

It looks like the key wasn't engaged in the flywheel just right. Take your time and learn to get in a habit of checking things twice........I'm slow at what i do compared to some guys, but I would rather take the time to make sure everything is just so before pulling that rope. Things go south fast at 7000 RPM.........

That tubing you cut of the ignition lead was there to prevent vibrations from rubbing thru and shorting out the lead. What do you plan to replace that with?

You get ready to trade that old Mac for a good running saw give me a call.

Im probably going to replace it with some of that heat activated shrink wrap wire insulation from home depot and Ill be sure to get it on the wire tight enough that it doesnt accumulate water or gas or whatever underneath.

Also, I thought the keyway was in there right, but i guess with the flywheel channel already being a little ate up when i got it off maybe there was some excessive play in there. Im thinking about just buying a new flywheel as a result. The crankshaft is true and centered when i spin it, and im almost certain that the flywheel was centered on the crank when i tightened it down, its just not perfectly round or true.... Never really seen anything like that.

Im going to make some phone calls today to source parts and no, im not going to sell this gem for a shiny new whatever, I may not have the wisdom and patience that some of you older guys have, but i have boundless energy and determination and I will make this thing look like new even if it take me down a winding path to get to it.

thanks for the offer though. :msp_wink:
 
Ok, got my carb kit and my hondabond4 from complete opposite ends of houston. I really am committed to doing this project right.

Also, is there anywhere local that might carry the crankshaft/flywheel key like home depot or lowes or ace hardware?

And should leave the flywheel to crankshaft mating surfaces bare and free of oil or should a put a dab of loc-tite or something on there?
 
Ok, got my carb kit and my hondabond4 from complete opposite ends of houston. I really am committed to doing this project right.

Also, is there anywhere local that might carry the crankshaft/flywheel key like home depot or lowes or ace hardware?

And should leave the flywheel to crankshaft mating surfaces bare and free of oil or should a put a dab of loc-tite or something on there?

Don't put anything on the taper, just degrease it with Brake clean.
 
ok i went and bought some hondabond 4 and a carb rebuild kit. Hopefully i wont have to tear the engine down but i do plan on resealing the leaking gas tank.

7FA28F3B-C294-406E-923E-CDA99A0B2E4D-538-000001303374B7EF.jpg


And then i started sandblasting and primering stuff.

before
25219A95-5548-4894-B38D-6060F299753A-538-000001377D124C5E.jpg


after
EDD3CEBE-263F-4969-8806-891946FF5855-538-0000013785C85B15.jpg


finally, should i JB weld these cracks and grind them smooth?
28A5B85C-7704-4613-81DB-C731250C5DF1-538-000001373DC6570A.jpg
 
Also, is there anywhere local that might carry the crankshaft/flywheel key like home depot or lowes or ace hardware?

If you know what size and type to get you can get the flywheel key at any hardware store. It would be easier to find at a local hardware store, not Home Depot or Lowes.
 
I would replace that flywheel, One off one of the other saws
should work. Many of the larger mac's use the same flywheel.
Is there a 250 in the batch you got? You can also lap the
flywheel to the crank with valve grinding compound. That will
make sure both surfaces are meant to be together. A flywheel
key you will have in one of your other saws as well. Also, Replace
the coil wire you cut the cover off of. Get one off one of your other
saws as well. It's great to have a few low dollar parts saws as
some parts will interchange.

I agree with Mastermind, Slow down before you ruin this classic
saw. Rome wasn't built in a day. Take it slow and pay attention.




Lee
 
If you know what size and type to get you can get the flywheel key at any hardware store. It would be easier to find at a local hardware store, not Home Depot or Lowes.

Actually im seeing them at autoparts stores online the most. Im about to go hit up an autozone or a orileys or something.
 
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I would replace that flywheel, One off one of the other saws
should work. Many of the larger mac's use the same flywheel.
Is there a 250 in the batch you got? You can also lap the
flywheel to the crank with valve grinding compound. That will
make sure both surfaces are meant to be together. A flywheel
key you will have in one of your other saws as well. Also, Replace
the coil wire you cut the cover off of. Get one off one of your other
saws as well. It's great to have a few low dollar parts saws as
some parts will interchange.

I agree with Mastermind, Slow down before you ruin this classic
saw. Rome wasn't built in a day. Take it slow and pay attention.

Lee

Wait, i want to make sure that i get this right. Are you saying that i should replace it because it appears out of round by a millimeter from one side to the other or because the inside is a little scratched up. Because Im thinking of using your valve lapping compound idea to clean up the inside mating surfaces and i cant find a NOS flywheel anywhere....

At any rate, im going to take your advice and swap the flywheels with another one that i have laying around here. I will use the valve lapping compound idea like you suggested however.

Anyhow, im headed out to buy a new woodruff key and some valve lapping compound and then when i get back this saw will be on the backburner while I assemble the new baileys 390 motor that i just got from the UPS man for my stihl 029 super. Soon as i get that thing running its going on the chopping block so i can mess with these two SP125's.


Finally, Im going to shrink wrap all the coil wires and try to source a NOS condenser even though the mini mac on on it now seems to be working and has the same part number stamped on it.
 
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I don't think your flywheel is out of round. It most likely
was not installed correctly. The key slot looked buggered
up. You don't need a NOS flywheel. You probably have
one right in front of you on one of the saws you got in that
pile. Even a right hand start flywheel will work. Just need to
put the starter pawls on that will come off the 125 flywheel.




Lee
 
Wait, i want to make sure that i get this right. Are you saying that i should replace it because it appears out of round by a millimeter from one side to the other or because the inside is a little scratched up. Because Im thinking of using your valve lapping compound idea to clean up the inside mating surfaces and i cant find a NOS flywheel anywhere....

At any rate, im going to take your advice and swap the flywheels with another one that i have laying around here. I will use the valve lapping compound idea like you suggested however.

Anyhow, im headed out to buy a new woodruff key and some valve lapping compound and then when i get back this saw will be on the backburner while I assemble the new baileys 390 motor that i just got from the UPS man for my stihl 029 super. Soon as i get that thing running its going on the chopping block so i can mess with these two SP125's.


Finally, Im going to shrink wrap all the coil wires and try to source a NOS condenser even though the mini mac on on it now seems to be working and has the same part number stamped on it.

Do you understand how the taper between the crank and flywheel works, that the key is for alignment and the taper does the actual holding?
 
finally, should i JB weld these cracks and grind them smooth?
28A5B85C-7704-4613-81DB-C731250C5DF1-538-000001373DC6570A.jpg

If you're looking to do a quality restoration, have the crack heliarc (TIG) welded, then grind the weld flush and paint. JB weld is a quick and dirty snot fix, not the proper way to restore something.

As to the flywheel, if it is out of round and wobbling on the shaft, they you'll have the issue of it being out of balance and damaging the crank bearings. Valve lapping compound is appropriate for removing light scratches and getting a flywheel tapered bore to a proper fit on a crank. Lapping is precise method of removing very small quanties of metal. 0.001" can take awhile to cut via lapping. If the tapered bore on the flywheel is really chewed up, which it appears from your picture, they you really need to consider finding a used flywheel.
 

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