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Stihl 044 Crank and case

Crispexx

Crispexx

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Jun 29, 2020
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162
Location
California
Evening all, I'm rebuilding an old 044 and I pulled the crank out of an old beat up crankcase and put it in a "new" crankcase. However after I put the halves together the piston arm appears to be rubbing on the bottom of the crank chamber. Sorry if my technical terms are a bit off. Are some older crankshafts not compatible with newer crank cases?
 

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OddSawz

OddSawz

Odd
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Jan 25, 2020
Messages
214
Location
TN
What is the size of your piston wrist pin? (10 or 12mm o.d.)

Is there a serial number on the case?

The lobes were different shapes on the crankshafts. It’s very possible you have a mismatch.
 
Crispexx

Crispexx

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Jun 29, 2020
Messages
162
Location
California
What is the size of your piston wrist pin? (10 or 12mm o.d.)

Is there a serial number on the case?

The lobes were different shapes on the crankshafts. It’s very possible you have a mismatch.
I haven't taken the piston off but I believe it is a 10. The old case serial number 9501970 the first part of the number is broken off. the new case number is 125905235
 
Crispexx

Crispexx

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Joined
Jun 29, 2020
Messages
162
Location
California
Probably a 12mm crank in a 10mm case. What does the flywheel side case near the muffler look like?

e09a70f777f2d470c278c507776416ce.jpg

These pics might not be good enough, I’ll get better ones in the morning. This is before I did any swapping or disassembly so the new case is the bare case in these pics.
e15f2f1a4bcf653752fc750365cfaf4a.jpg



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pioneerguy600

pioneerguy600

Lost in Space
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Dec 23, 2007
Messages
40,782
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N.S. Canada
This problem was common when swapping a 12mm crank into a 10 mm case but I have not encountered a problem swapping 10 mm cranks between other 10mm cases. It does not hurt to either remove some metal from the crankcase to allow for clearance or remove a bit off the crank and rod big end to allow for clearance. Have done so myself on several builds.
 
Crispexx

Crispexx

ArboristSite Operative
Joined
Jun 29, 2020
Messages
162
Location
California
This problem was common when swapping a 12mm crank into a 10 mm case but I have not encountered a problem swapping 10 mm cranks between other 10mm cases. It does not hurt to either remove some metal from the crankcase to allow for clearance or remove a bit off the crank and rod big end to allow for clearance. Have done so myself on several builds.

Yea I’m going to check and make sure it’s a 10 mm wrist. When I got the saw it was a bit of a Frankenstein’s monster.


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