McCulloch Chain Saws

[Maintenance supervisor]

I'm yet to paint one of my old saws, i like my old stuff left as is. I enjoy getting them running & plan to use them so i just clean & fix issues. Might change one day though???

I need to find a good sealant for the 10 series fuel tank. I've seen the viton one's online but with shipping & import fees to Austrailia, they're worth more than I've paid for my saws...

I have a few with battle scars ( pro mac 60) , but I am mostly concerned about corrosion so I use farm industrial equipment paint and automotive paint to deter the White Death. I have a 10-10 righty that had the flywheel cover rotted on the bottom like your 55.

 

[Ben79]

I have a few with battle scars ( pro mac 60) , but I am mostly concerned about corrosion so I use farm industrial equipment paint and automotive paint to deter the White Death. I have a 10-10 righty that had the flywheel cover rotted on the bottom like your 55.

I wonder what causes the rot? I was thinking sitting cold cement for years or salt damp??

 

[2broke2ride]

I.also.need to know about the rings. About to re-ring the 5-10 and need to know if there is any specific orientation.

 

[Goinwheelin]

Dimples on the rings face down towards the skirt of the piston. Just did my 7-10 and those instructions were in the box.

 

[heimannm]

The dimple, or "pip" or dot go down or towards the crankcase, away from the top of the piston as wheelin notes.

Mark

 

[kbeck]

The dimple, or "pip" or dot go down or towards the crankcase, away from the top of the piston as wheelin notes.

Mark

installing rings on my pro mac 60 today not sure what were talking about with dimple/pip
my piston does not have the locating pins in it was just going to install rings as if there were locating pins
in piston for rings, are we talking about the same thing. Thanks

 

[vizette]

installing rings on my pro mac 60 today not sure what were talking about with dimple/pip
my piston does not have the locating pins in it was just going to install rings as if there were locating pins
in piston for rings, are we talking about the same thing. Thanks

I don't have a pic of my specific rings on hand, but see in this picture, the one ring looks like it has a little mark, or divot in it? Maybe it's only for rings on pistons with locating pins? Not sure what the history is there...

Thanks to all that replied!

 

[vizette]

I wonder what causes the rot? I was thinking sitting cold cement for years or salt damp??

Long version:
https://www.intechopen.com/books/ma...ion-and-surface-treatment-of-magnesium-alloys

http://www.totalmateria.com/Article19.htm


short answer: it's very prone to galvanic reaction/attack unless protected. I was reading somewhere that you shouldn't even scrub it with a wire brush because it can embed in the magnesium and will continue to corrode even after covered/painted (dissimilar metals). That might be an extreme case though.

There are environmental factors that can accelerate the process.

Concrete is definitely not good. I assume due to moisture, and just general abrasion wearing off the protective paint.

Trying to find someone now to tig weld a gas tank on a super 250 that has a finger size hole in it due to general corrosion. Will have to seal up the tank with something after, the entire interior of the tank looks like the moons surface. Might end up being a JB Weld job...

 

[Goinwheelin]

Body filler might work too

 

[PogoInTheWoods]

Not all rings will have orientation indicators. Some ring sets also include two different ring types. In cases where a chrome ring is part of the set, it is the top one, as I *think* would also be the case with a set that includes one ring with a beveled edge (with the angle of the bevel downward) -- but don't quote me on the latter. That may actually be the chrome ring in a mixed set I'm thinking of. Maybe Mark or someone else could add clarification there. I stagger end gaps from one another on the intake side for non-pinned pistons as would typically be the orientation with a pinned piston.

Would love to get goin' on this 7-10 any day now but Bob would seem to be a little behind this week. Last order from him took almost two weeks. Actually had to call him about it. Was still sitting there on his counter 10 days after I ordered. I'm keeping my fingers crossed for delivery tomorrow on this one.

 

[Maintenance supervisor]

Long version:
https://www.intechopen.com/books/ma...ion-and-surface-treatment-of-magnesium-alloys

http://www.totalmateria.com/Article19.htm


short answer: it's very prone to galvanic reaction/attack unless protected. I was reading somewhere that you shouldn't even scrub it with a wire brush because it can embed in the magnesium and will continue to corrode even after covered/painted (dissimilar metals). That might be an extreme case though.

There are environmental factors that can accelerate the process.

Concrete is definitely not good. I assume due to moisture, and just general abrasion wearing off the protective paint.

Trying to find someone now to tig weld a gas tank on a super 250 that has a finger size hole in it due to general corrosion. Will have to seal up the tank with something after, the entire interior of the tank looks like the moons surface. Might end up being a JB Weld job...

Ive used jb slow cure in a tank an it works fantastic, just give it a week.
The worst "rot I've seen on this site was from dog piss ,so draw your own conclusions, but if it looks to be working on a saw I clean and paint.

 

[mogulmasher]

Interesting the dimples go down. In all the small block Chevy's I have built dimples in the rings go up. Learn something new everyday! Before reading this I'd have installed Mac rings upside-down just out of habit.

 

[vizette]

Ive used jb slow cure in a tank an it works fantastic, just give it a week.
The worst "rot I've seen on this site was from dog piss ,so draw your own conclusions, but if it looks to be working on a saw I clean and paint.

Here's the tank rot. If I can't get someone to tig it, JB it is! If I'm gonna coat it anyway, doesn't matter if I get it 100% sealed with JB either. Just need to figure out how to get all that gunk out of there. I really need to get a blasting cabinet...

 

[PogoInTheWoods]

So are those rings beveled? (Mac)

 

[PogoInTheWoods]

I really need to get a blasting cabinet...

That's the only way I would approach prepping that tank for repair regardless of your patching method. Shouldn't cost much to have it done if you don't want to spend the money on your own setup.

 

[kbeck]

I don't have a pic of my specific rings on hand, but see in this picture, the one ring looks like it has a little mark, or divot in it? Maybe it's only for rings on pistons with locating pins? Not sure what the history is there...

Thanks to all that replied!

View attachment 799940

I don't have a pic of my specific rings on hand, but see in this picture, the one ring looks like it has a little mark, or divot in it? Maybe it's only for rings on pistons with locating pins? Not sure what the history is there...

Thanks to all that replied!

View attachment 799940

My pistons didn't have locating pins for the rings but the rings that came with them had the grooves in them for locating pins or whatever there called.
I installed them as if there were locating pins in pistons. No dimple in rings used the aluminum can wrap to compress the rings. hope it turns out

 

[heimannm]

For that tank repair I doubt TIG is a valid option given the condition of the material. After sand blasting put some tape over the hole (on the outside just to be clear) then apply the JB Weld to in interior of the tank. You can press a piece of window screen wire into the JB if you feel you need additional strength. After the JB fully cures you may need a bit of filler to smooth out the edges but you may get by with a simple sand and paint.

Here is a flywheel cover I repaired that way.









Mark

 

[Jethro 2t sniffer]

For that tank repair I doubt TIG is a valid option given the condition of the material. After sand blasting put some tape over the hole (on the outside just to be clear) then apply the JB Weld to in interior of the tank. You can press a piece of window screen wire into the JB if you feel you need additional strength. After the JB fully cures you may need a bit of filler to smooth out the edges but you may get by with a simple sand and paint.

Here is a flywheel cover I repaired that way.

View attachment 800077

View attachment 800078

View attachment 800079

View attachment 800080

Mark

That came out really nice Mark and love the "rebar" thrown in the pour too very nice touch.

Yeah the TIG will hate all that yucky metal you'll wind up with a bigger mess than when you started. It will need to be ground right back to clean metal and probably not alot left of it

 

[vizette]

Is there an option to cleaning this mess other than soda blasting? Anyone got an extra super 250 tank?

 

[Mac 6-10]

@PogoInTheWoods was asking me to pop in for a little insite on 10 series rings.

As far as the rings go, only the cast or thick rings have the dimple. and only the ones that are designated to run in chrome bores. they have a taper on the face of the ring and if put in upside down they wont seal against the cylinder wall. they do this for quicker break-in since the chrome has low friction.

the cast thick rings for iron bores are just standard square rings

the thin rings are steel and can be used in either chrome or iron bores. and orientation does not matter.

end gap can be anywhere on the intake side of the cylinder inbetween the transfers. keep them out of the transfers and the exhaust or you will snag a ring.