McCulloch Chain Saws

[El Moobs]

@El Moobs

I believe he knows where on is for sale.

I have several to sale.

 

[hseII]

I have several to sale.

I take commission.

 

[El Moobs]

I take commission.

"Love It"

 

[hseII]

"Love It"

Let me find my screwdriver.

 

[hseII]

Let me find my screwdriver.

 

[Mac&Homelite]

So I have a dilemma on my hands again. I am trying to change my Mac 250 clutch drum from a .404 spur drive to a replaceable rim drive sprocket in 3/8.
Here's the link to what I purchased. http://m.ebay.com/itm/381981236667?_mwBanner=1
The problem is that the od of the shaft on the saw is larger than the id of the clutch bearing.

Do I have the wrong clutch, or is it possible to buy a new bearing that has the right dimensions?

 

[heimannm]

You can change the bearing.

I think the two diameters were 1/2 and 9/16", older saws with the straight shafts were larger, later saws with a tapered crankshaft were smaller...if I recall.

Mark

 

[ML12]

Mark is correct about the 9/16" shaft on the older saws for sure. The clutch drum you have will work, but the bearing needs to be replaced.

I have a couple new 3/8 clutch drums sitting around for the large frame saws with no bearings because I couldn't order the right size needle bearing through the local bearing house. (0.6875" OD x 9/16" ID x .6875" Lg) My plan is to buy bronze bushing stock and make a bushing for them. My 1-50 has a bronze bushing in it from factory I think.

its a matter of finding time right now though. There are only so many hours in the day. And they run ok with .404 for now

 

[Mac&Homelite]

If my measurements serve me correctly, this drum bearing od is .748 inches. So a new bearing shouldn't be too hard to find. I hope...

 

[Mac&Homelite]

I'm trying to figure this out, but the new sprocket bearing is a 9/16 id and the old one is a 5/8 id. What's up with this now? I suppose out of all the saws I could have gotten, I got the special model lol. Bearing on the old one is a Torrington b 1010 for reference.

 

[Mac&Homelite]

So after some research, I could not find a needle bearing that had a 5/8 id by 3/4 od by 5/8 wide which is what I ideally need. The closest match I can find is a 5/8 id by a 13/16 od which leads me to my next dilemma. Do I have the clutch machined out to 13/16 to accept the bearing I can find, which is also the same original bearing, or do I switch to a sintered bronze bushing, of which is easily accessible in the 5/8 x 3/4 flavor? Thoughts?

 

[emf123]

You could use a socket and hammer the bearings out of the clutch drums and swap them. I think I've done that before.

 

[Mac&Homelite]

You could use a socket and hammer the bearings out of the clutch drums and swap them. I think I've done that before.

I would do that except the od on the old bearing surface is 13/16 and the od on the new is 3/4. Slight difference in size.

 

[emf123]

I'd get a different clutch drum then, you got a pretty old part number. I started putting together a list of different clutch drums with Mac and Oregon part numbers, hopefully this helps.

 

[Mac&Homelite]

Helpful chart, thank you! Then, does anyone have an id measurement for the Oregon 10624 drum? My shaft is definitely not 9/16, so I would like the id for the drum so I can see if I can insert a 5/8 needle bearing inside. The minimum id I would need for that is 13/16.

 

[emf123]

The bore of an Oregon 10624 drum is .685", so that won't work.

 

[Mac&Homelite]

Well I decided on a bronze bushing for the time being. Comes in 5/8 x 3/4 and pressed right in. Id was a little tight so I honed the surface a little bit with emery tape. Spins great now, and should hold up fine for the limited use it will see. That completes my bar and chain conversion for this saw. Hopefully will try it out in wood tomorrow.

 

[emf123]

Now you just need a different bar that ain't right at all!!

 

[ML12]

Nice work! Looks great

 

[heimannm]

Make sure you put a little grease under the bushing to minimize friction...and change that bar.

Mark