Jerry Cochran

Well Known Member
After searching the net and finding no joy, decided to ask this question at the ultimate authority, VAF!

Does anyone know the flange runout limits for an (I)O-360 AIA? Oh, and maybe a link to the source?

Thanks all,
Jerry
 
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IIRC the source of this info is Lycoming's Overhaul Manual

however, don't remember off of top of my head what the runout value is..
 
After searching the net and finding no joy, decided to ask this question at the ultimate authority, VAF!

Does anyone know the flange runout limits for an (I)O-360 AIA? Oh, and maybe a link to the source?

Thanks all,
Jerry

Don't have a source to direct you too but from memory I think the max is .002" and the max. that is repairable is .018".
 
The lycoming manual I have shows manufactures Crankshaft Prop. Flange Run-Out min / max as .002 but then list service max as .005. There are also instructions in the manual for checking the run out and allowable limits that can be corrected. If you wish I can email you a copy of the page from the manual.
 
Table of limits

Yes the source is the Overhaul manual 60294-7. In the back is the "Table of Limits. It says .002 as the mfg. max and .005 as the serviceable max.

I read that to say if it's .005 or less you can fly it.

I didn't see anything about how bad is non-repairable. The shops that repair cranks will know the answer to that one.

Mark
 
.005" is it.

The reason I know is my crank dialed .070". Anyone want to buy a slightly used O-290-D2?
 
.005" is it.

The reason I know is my crank dialed .070". Anyone want to buy a slightly used O-290-D2?

Yea, the crank in the engine on the wrecked 6A I rebuilt dial about .090 " runout. You could see it was bent just looking at it from the side.

I am pretty sure the repairable limit is .018 ". The face of the flange is surface ground to resquare it to the crankshaft center line and then the flange is re-cad plated (all this only done after the rest of the crank has been inspected for damage of course).
 
SB 201E is the answer

After searching the net and finding no joy, decided to ask this question at the ultimate authority, VAF!

Does anyone know the flange run out limits for an (I)O-360 AIA? Oh, and maybe a link to the source?

Thanks all,
Jerry

Jerry,
This is all detailed in Service Bulletin 201E. I'll shoot you a copy off list. There is also a minimum flange thickness, which varies according to model.
Charlie Kuss
PS If it can be fixed, Aircraft Specialties will charge $210. See

http://www.aircraft-specialties.com/mach.html
 
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Thanks to all who replied. I also noted in my Superior OH manual for O-360 that it says max "Crankshaft Flange O.D. Run-out" is 0.0050 T.I.R., anyone know what "T.I.R." is?
 
Thanks to all who replied. I also noted in my Superior OH manual for O-360 that it says max "Crankshaft Flange O.D. Run-out" is 0.0050 T.I.R., anyone know what "T.I.R." is?

Jerry,
I believe it means "total indicated run out". You generally check this using a dial indicator. I own one that has an assortment of screw on ends. One end contains a wheel, making it perfect for checking crankshaft flanges and brake rotors.
Charlie Kuss
 
O-360-A4A total flange run-out

Just to be certain, if the crank dialed out to 0.008, then there's a good chance the crank can be repaired? I know that you don't want to fly with it, but is that repairable, and if it is, typically, what ball park figure are we looking at to repair it?

Thanks


Don