Non VAR Crankshafts

tomcomet · #1 09-27-17, 11:30 AM

I am just in the process of (maybe) purchasing a 1977 F337G and found out it definitely has the non VAR crankshafts. From what I see in this Critical Service Bulletin it would appear that I need to change them to VAR cranks when the crankcase is opened up.

http://www.tcmlink.com/pdf2/csb96-8.pdf

What about TBO? Some say this Critical Service Bulletin limits me from flying the engines "on condition". These engines are at 1440 hours and counting... Can someone please confirm? I have a call into Continental as well but so far nothing back from them.

Thanks!

hharney · #2 09-28-17, 02:32 PM

COMPLIANCE:
Engine overhaul or whenever the cranks
shaft is removed or made accessible by
crankcase disassembly.

It is not an AD so not required until the above is performed in the USA. I assume Canada too

tomcomet · #3 09-28-17, 04:18 PM

Quote:

Originally Posted by hharney

COMPLIANCE:
Engine overhaul or whenever the cranks
shaft is removed or made accessible by
crankcase disassembly.

It is not an AD so not required until the above is performed in the USA. I assume Canada too

Yes, this is what others are saying as well. Good news!

LostKiwi · #4 09-29-17, 06:00 AM

Sorry to be the bearer of bad news:

Ref AD 97-26-17:
http://rgl.faa.gov/Regulatory_and_Gu...B?OpenDocument

TL,DR: At the next engine overhaul, or whenever the crankshaft is next removed from the engine... ...remove the crankshaft from service and replace with a serviceable crankshaft manufactured using the VAR process.

Can you still run your engine on condition? Yes. Absolutely. BUT... you gotta replace the crank on the next overhaul, thats non-negotiable.

Leighton.

tomcomet · #5 09-29-17, 06:47 AM

Quote:

Originally Posted by LostKiwi

Sorry to be the barer of bad news:

Ref AD 97-26-17:
http://rgl.faa.gov/Regulatory_and_Gu...B?OpenDocument

TL,DR: At the next engine overhaul, or whenever the crankshaft is next removed from the engine... ...remove the crankshaft from service and replace with a serviceable crankshaft manufactured using the VAR process.

Can you still run your engine on condition? Yes. Absolutely. BUT... you gotta replace the crank on the next overhaul, thats non-negotiable.

Leighton.

Got it. Thanks everyone! Also, I just spoke with Continental and the good news there is they do not charge extra to take back my non-VAR crankshaft engine if and when it goes back. No penalty so that is good.