FAA 337 Info

Not so much a forum question, although I guess it could be. As a recent new member to a Flying Club, with a 150G &182H, and volunteering to assist with maintenance, we recently had to replace a main wheel during our annual due to a spun wheel bearing race. It was actually pretty loose and not sure if any of the typical ways of repairing them (from trailers, cars, etc.) would have worked, so we sourced a used wheel.

But I'm now concerned about similar issues in the five other 50 year old wheels we have in our aged fleet. In discussions with others, if needed, a recommendation was to attempt a repair with some flavor of Loctite to secure a loose race, and ask out IA to complete a 337 to document that repair, with the assumption this is less expensive than replacing the wheels. Our IA however said that the 337 is not a simple process, and requires the FAA to review and inspect the work, and could involve considerable time, and thus money. And therefore something he'd rather not do. He gave tale about a West coast plane coming in with a 337 approval for a non-standard instrument, and the local FSDO never came by to approve another 337 for a similar install in another aircraft.

So here's the question: Is there, or could there be, an article for going about the 337 process for the 337 process for owner/operator assisted repairs / modifications? The form itself seems rather clear and simple, but the process behind submitting it isn't.




    The issue with writing a 337 is that the form is intended to document approval of a repair or alteration BASED ON APPROVED INFORMATION. By "approved" the FAA means approved by the FAA - either in the manufacturer's maintenance manual, in the FAA approved methods circular, or approved by STC. There would not be any approved data for a wheel bearing installation with Loctite, since that is not in the AMM or in FAA standard practices. Because there is no approved data, your A&P/IA cannot write a 337 on that repair.
    I suspect that there are a few wheels out there with loose bearing bores patched with Loctite, but if I found one of them during an annual inspection I could not sign off on it.
    The best course of action on an older Cessna with damaged McCauley wheels is to either buy an airworthy wheel from a recycler, or plan on installing a changeover kit to Cleveland wheels/brakes. The Cleveland install is not an inexpensive change, but way better than risking wrecking the entire airframe due to a wheel bearing getting loose, or a wheel cracking. And it does give you new wheels, brake disks and calipers, wheel bearings, etc for which new service parts are available.

  • Scott ShererScott Sherer COO Forum Moderator

    Very insightful, Jerry. Thanks for your comments. Much appreciated.

    Scott Sherer
    Wright Brothers Master Pilot, FAA Commercial Pilot
    Aviation Director, Cessna Owners Organization Forum Moderator and Cessna Owners Author.

    Need help? Let me know!

  • Thank you both for your comments. So this is where some kind of article I think would be helpful for owner / operators, from an IA or FAA / FSDO perspective.

    We previously received advice - from another forum - that I believe meant that an A&P / IA could submit an 337 for such a repair, however as stated our IA was hesitant, but for different reasons as given in my original post.

    That other reply, also from an IA / A&P was:
    "I think there are only two choices to satisfy your mechanic. The first requires trashing the wheel halves, which is an expensive and unnecessary option. The second option is that your mechanic could develop a form 337 repair approval, which would be less expensive and make the job FAA-legal"

    We went with a serviceable used wheel, and we're going to inspect all of our other wheels soon, but now we have three different points of view on this:
    1 - doable with 337 (other source)
    2 - doable with 337, but expensive, time-consuming and likely not worth the hassle (our IA)
    3 - not feasible, your view.

    So all three view points are different. Is it possible all three are valid, but up to the discretion of the local FSDO?

    Again thanks,

  • Oh, and just to throw another wrench into the mix, could an owner produced part fit anywhere into this scenario, or anything similar? Again, a generalized take on a situation where one is faced with repairs to aging aircraft with limited parts availability.

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