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337 needed for C85-8F

Hansolo

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I need a copy of a 337 to install a C85-8F on a J3C-65. Also looking for a wood prop W72GK-46. Thanks

Mike
 

Renkou1

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Know where you are coming from...however there is a factory letter floating around that says the flange shaft is a direct replacement part for the taper shaft.
Thought I'd be the first to say it.
 

Renkou1

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Found service bulletin M47-16 rev.
State you will need to do 337 and states this is a normal overhaul operation. Crankshaft seal change mentioned as the only other part change required. A new data plate is available after market as I understand Contiental will not supply.
 

Fly_cubs

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The best thing you can today for the paper work to put the C85-8F on any of the J3 airframes is to purchase the Paul Babcock STC. PM me for his number. $300 bucks I think- and it comes with a lot of extra information that is very helpful.
 

Hansolo

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Just read the Babcock STC. It does not cover the C85-8F. I don't need a new data plate because the engine came as an F. I just want to hang it on my cub with the proper paperwork. Will look at the SB's later today.
 

huston marlowe

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In its history my Cub has had a C-85-12 and now has a C-85-8F .. Both installed with log entries only..The legality of the engine installation has never been questioned by the three IAs I have had...although they have been very careful to check stuff like the prop and carb etc. What would happen if you "just do it" ?
 

JimC

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Huston, your C85-12 was on the TCDS. No paperwork required for it.

Hansolo, you may need the aid of a DER to be legal.
 

Hansolo

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That's what I was afraid of. I thought that if I had a couple of approved 337's along with the Continental Overhaul Manual/SB's etc, I could get an inspector at the FSDO to sign it off. I know it's just a minor change but.... My kids will be flying her soon, so I just want it to be right. My friendly IA won't be around forever. By the time I hire a DER I could probably to the Stroker conversion... Arrrrg $$$
 

JimC

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If you can find an approved 337 dated prior to the cutoff date in late 1955, it can be used as approved data for a new 337.

I can't advise that you do it, but most folks just mount the F's and truck on. My J3 ran an 85-12F for years, but that was back in the 60's and 70's when it wasn't an issue.
 

tophand

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I've been trying to post here since yesterday but it keeps messing up. You need to do a 337 because you are overhauling the engine. You send that to OKC. OKC doesn't care. Continental views the parts as interchangeable.

I'll keep trying to post the ACs & SBs


.........Mike
 

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