Can I replace landing gear u bolt on 1967 7ECA

Hayduke

Hayduke

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May 7, 2019
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I'm considering purchasing a 1967 7ECA, spring gear, O-235. It still has the original U-bolts. The current owner says that the way the aircraft fabric was installed that it cannot be upgraded to the steel bar bolts that are less prone to breaking. The owner says that they pull the current bolts each annual and inspect them and reinstall.

I haven't heard anyone else mention that they couldn't be upgraded. Given I'm doing an annual for a pre-buy, what should I do? I feel like I should just put new ones in if we pull them during the inspection, in part because I envision a few rough landings during my getting up to speed phase on a Citabria.

I tried the search and read a few posts on u bolt replacement but haven't come across this issue before. Also, does anyone have a link to where I can buy new replacement ubolts if I can't upgrade?
 
Upgrade. Should bolt right on. The fact that they pull those U bolts off every year would worry me.

Consider replacing all bolts - six total - with NAS bolts. Expensive - expect $30 each! But worth it. Need special washers for them.

ACA sells the bolts - six years ago they wanted $130 each! Shop wisely.
 
image.webpimage.webpimage.webpimage.webpShould be easy to change hope this helps. You still need the two inside bolts I just couldn’t put my hands on then right now. I’ll search some more later to see if I have the part numbers.
 
Replacing the inside bolts is not part of the mod - but it does relieve you of the non-mandatory 50 hour torque check.
 
I think it suggests somewhere on the ACA site if your operating on rough terrain. Change the bolts out every 500 hrs. They go on to say when you torque them and recheck on the Annual. If they require a re-torque, the bolts have been stretched from wear and tear. Too much stretch, they fatigue and snap. Not good, hence the 500 hr suggestion.
 
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Thanks a lot for all the info. Now I need to follow up with his AP/IA to figure out why they say this modification can't be done due to a "fabric" issue. I don't understand why this wouldn't be straight forward to swap out.
 
They are probably confusing the aluminum gear leg mod with the bar mod. Get the ACA paperwork. It is a bolt-on.
 
you might have to trim the back edge of the boot cowl to make it fit around the new gear mounting hardware.
 
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U1-9805A AERONCA LANDING GEAR U-BOLT

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Doesn't say whether it is one side or a pair, and the nuts are $28 each! Still, losing a gear leg can be expensive - this, and the expensive NAS inner bolt, is a good investment. That, from a guy who usually cheaps out.
 
Pretty sure I got all my hardware through Aircraft Spruce. Note that the description says it doesn't come with the bolts, but it does. I returned my bolts for credit. I replaced the inner bolt at the same time. Also upgraded the tail wheel to the new "U-bolt" which uses the same bar+ 2 bolts that the main gear uses.
I believe the 500 hour thing says replace, not inspect.
And not that anyone asked, but my IA says he's seen them about to break before but it was never at the corner of the "U", it was at the threads right under the bolt. No way to inspect that without removing the nuts and I bet almost no one does that.
 
"says he's seen them about to break before but it was never at the corner of the "U", it was at the threads right under the bolt"

That sounds reasoned as that's a stress point as well everytime the nut is re-torqued.
 
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