Mac 1-52

[Tzed250]

The connecting rod has the greatest amount of leverage on the crank when it is perpendicular to a line drawn from the crank centerline to the rod journal. Longer rods put more force into the crank, and less force as side thrust of the piston into the cylinder wall. The big end journal may not have been heat treated correctly.

 

[heimannm]

So Brad

The day I leave Cincinatti you get going on the old McCullochs? We did get the deck up to snuff but it took most of the weekend to complete the work.

Get some good dimensions off the crank shaft and I will see if any of the 200/250 parts saws I have would match up.

Bob Johnson (Bob's Lawnmower) may have the grommet you need for the airbox/carburetor. If not, give me some dimensions for that as well. I have some new (from Bob) as well as used parts on hand. The HL63 is indeed a Tillotson and much easier and less expensive to work on if needed.

I have a few new 4 tooth and 5 tooth spikes put away, and I thought I got the last 4 tooth that Bob had. I got a new 5 tooth from him just a few weeks ago.

Most of my 1-50 series saws have the full wrap handle. May not make it more useful but the do look good.

Mark

 

[blsnelling]

The rod and needle bearings look great. You would have thought they would have gotten chewed up as well.

 

[Tzed250]

The rod and needle bearings look great. You would have thought they would have gotten chewed up as well.

The softest metal takes the beating...rollers are probably ASTM 52100

 

[blsnelling]

Any chance this crank would be the same as in my 1-52? They look similiar and the bore and stroke is the same. Got a part# on a Mac 200 crankshaft Calvin? LINK

 

[buzz sawyer]

The rod and needle bearings look great. You would have thought they would have gotten chewed up as well.

Same with my EZ but I installed a different set of needles that came with a good used piston and rod. Found a new crank too.

 

[blsnelling]

I've got a couple more questions for you. How many needles are supposed to be in the 1-52? I counted 24 but it looks like it needs one more. Is the crank in a 1-41 the same?

 

[PES+]

No at least not a drop in

The 1-52 is 1-1/2" stroke....the 1-41 is 1-3/8ths stroke.

I am still rummaging around looking for cranks for you but everything I have found so far in good shape is the 1-3/8ths.

The port heights are different in the two different stoke blocks.

You could change out the block and run the 1-41 in the 1-52 chassis

But the 1-41 has no piston pin bearings (it used bushings) so you would want to use the 1-52 piston with new piston pin bearings on the 1-41 engine.

But then it will also be smaller displacement which does not go over well in this place.

24 needles is the correct number

Post some pics of the crank and needles

 

[lawnmowertech37]

Any chance this crank would be the same as in my 1-52? They look similiar and the bore and stroke is the same. Got a part# on a Mac 200 crankshaft Calvin? LINK

50659 part #

 

[blsnelling]

Thanks a ton for the info guys. How about a Mac 200 crank? I'll have to get a pic of the needles. And no, I couldn't possibly go smaller in displacement

 

[blsnelling]

I'm confiused how the stroke of the two cranks could be different if the bore, stroke, and displacement of the two engines is the same. Another source has told me that the crankshafts out of the following models all interchange.

Mac 15, D-30, D-36, 1-40, 1-41, 1-42, 1-43, 1-45, 1-46, 1-50, 1-51, 1-52, 1-53, 200 and 250.

Here's the pics of my crankshaft and needles.

 

[PES+]

The 1-52 and 1-53 are indeed 1.5 stroke.....all the others you listed are 1.375

Better have your source check again

You can use a 300, 380, 380A, 440, 450, 1-52, 1-53

The 1-52 and 1-53 are 5.3 cubic inch all the rest are 4.9 CI from your list.

All the 5.3 CI in the time frame used 2 ball main bearings.

The 4.9 CIs used ball bearing on the mag side and needle bearing on the clutch side

 

[AngelofDarkness]

I thought I would add a lil something to this thread. My neighbor was watching me try out my flea market SXL-AO I had brought back from the dead and he said he had an old saw that I could look at if I wanted. I said sure and he brings me a 1-42 that's a bit beat up but all there. Problem is it is locked up tight, I mean really really tight. I poured oil down the plug hole and even hit it with an impact wrench on the clutch side, nothing. I can't get it to budge. Any ideas other than pulling the jug?

 

[PES+]

You can measure it yourself if you put the bearings back on the crank and put the crank back in the block

Real simple to do just a ruler and a straight edge across the base where the stuffer plate/oil tank mounts up.

 

[blsnelling]

Acres has the 1-52 and 1-53 listed as 4.9 CI, 80cc. I did measure the stroke on mine at 1.5". Is Acres info wrong on both saws?

 

[PES+]

Yes

 

[blsnelling]

I see his error now. He has the bore right but the stroke wrong. Thanks for clarifying that.

I just found that he has the 300 wrong as well. It's listed with a 1.375 stroke, 4.9 CI.

 

[PES+]

I thought I would add a lil something to this thread. My neighbor was watching me try out my flea market SXL-AO I had brought back from the dead and he said he had an old saw that I could look at if I wanted. I said sure and he brings me a 1-42 that's a bit beat up but all there. Problem is it is locked up tight, I mean really really tight. I poured oil down the plug hole and even hit it with an impact wrench on the clutch side, nothing. I can't get it to budge. Any ideas other than pulling the jug?

There is no "jug"

that will most likely be a parts saw only as it most likely had water in it and the bearings are all seized tight. OR it threw a needle and the engine block is wasted along with the piston at least.

 

[blsnelling]

The 1-52 and 1-53 are indeed 1.5 stroke.....all the others you listed are 1.375

Better have your source check again

You can use a 300, 380, 380A, 440, 450, 1-52, 1-53

The 1-52 and 1-53 are 5.3 cubic inch all the rest are 4.9 CI from your list.

All the 5.3 CI in the time frame used 2 ball main bearings.

The 4.9 CIs used ball bearing on the mag side and needle bearing on the clutch side

I really appreciate this info. Did you happen to find a good 1.5" crank? What about this one? LINK. He still has it available. I thought the turned down area for the clutch drum looked smaller than mine. It's hard to tell in a picture though.

 

[AngelofDarkness]

There is no "jug"

that will most likely be a parts saw only as it most likely had water in it and the bearings are all seized tight. OR it threw a needle and the engine block is wasted along with the piston at least.

Oh boy, that doesn't sound good. I will try and split the case and see what I can find. I really wanted to get it running. Oh well....