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Counterweighted/Non Counterweighted Crankshafts

Low Pass

Well Known Member
Friend
After believing I had found a deal on a serviceable crankshaft to replace one from an O-360-A1A, I have been thrown a curve. The replacement crankshaft is counterwighted. (Owner referenced p/n for IO-360-A1A.) My original failed crank is non-counterwighted. Can a counterweighted crank be used in a non-counterwighted application?

I would be grateful to hear any actual experience or first-hand knowledge related to this issue.
 
crank

I have a 200hp Lyco that did not have C/W when I purchased it sent the crank to Aircraft Specialties Services and had new C/W's installed no changes to case.
Bob
 
cranks

The A1A is not a counterweighted crank. If he has a 200hp crank the rods will be different. May be a wash if you had to buy rods with it. Counterweighted would be a IO360A1B6. I have an extensive list of crank part number and if you get me the LW numbers off the flange of the crank I can tell you what it fits.

Jesse
970-874-7575
 
The A1A is not a counterweighted crank. If he has a 200hp crank the rods will be different. May be a wash if you had to buy rods with it. Counterweighted would be a IO360A1B6. I have an extensive list of crank part number and if you get me the LW numbers off the flange of the crank I can tell you what it fits.

Jesse
970-874-7575

Thanks Bob, Jesse. I appreciate the info and offer of assistance. Way more -360 series crank p/n's than I had imagined. And I am going to have to buy rods. They failed as well. Same person can source compatible yellow tagged rods for me also. It's not been a good overhaul so far...
 
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Lycoming Parts

Bob Merril at Aircraft Specialty in Tulsa is another great resource on the engine parts. He is extremely knowledgeable and can answer your questions.

Don Broussard
RV9 Rebuild in Progress
57 Pacer
 
Rods

Thanks Bob, Jesse. I appreciate the info and offer of assistance. Way more -360 series crank p/n's than I had imagined. And I am going to have to buy rods. They failed as well. Same person can source compatible yellow tagged rods for me also. It's not been a good overhaul so far...

I have a set of yellow tagged rods that should work for you.

theduff at EarthLink dot net

Duff
 
I have a set of yellow tagged rods that should work for you.

theduff at EarthLink dot net

Duff
Thanks very much for the offer!! I believe I have a nice package deal of tagged parts. If it falls through, I'll keep you in mind.
 
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