The journey begins. 170B project.

How to keep the Cessna 170 flying and airworthy.

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Bruce Fenstermacher
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Re: The journey begins. 170B project.

Post by Bruce Fenstermacher »

n2582d wrote:Bruce,
I agree that such a swap should be done in consultation with one's local FSDO but I doubt if it would require a 337 form. In this case one is replacing the same part number, not going to a later or different Cessna model wing. It is not a major alteration or repair which is what a 337 form would be used for. Might it not just require a logbook entry detailing the swap? One catch might be how the airframe logbook total time is calculated. Say you put an 8000 hour wing on a 3000 hour fuselage. Do you now include "wing total time" and "fuselage total time" in every logbook entry?
Yes Gary I completely agree. I sometimes forget that my own 170A with what was described as 170B wings in the logs, but turned out to be L-19 wings, had a lot more going on in the changed from original department, making a one time approval on a 337 more inviting for the mechanic.

If I was actually doing this myself, swapping a 170B wing with a 172 wing, I'd be going out of my way to show that the new assembly is actually a part for part replacement of the old assembly and thus only a minor alteration. This is pretty easy I think. the 170 right wing assembly for example is 0523005-1. This is the same part number for the 172 initially. But the 172 part manual has a 0523005-200 superseding the original. Basically all wing assemblies for the 172 serial 28000 to 17249544 (or through the G model) and all wing assemblies for the 175, can be shown to be exactly the same as that used in the 170B. It is important to note the fuel system is not part of the wing assembly.

Armed with this information, I'd visit with my mechanic. Don't be surprised if your mechanic wants to visit with the FAA. And before he visits with the FAA, I'd arm him with all the help of support from Cessna that Cessna will give.

In the end I wouldn't be surprised that the repair is documented with a form 337, right or wrong.
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Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

The verdict is in. I spoke with my local FSDO this morning and luckily got a guy that's been around and dealt with this very issue and very matter of factly stated that "if you can show the part numbers are the same.....you're good to go. No 337...just a logbook entry, BUT, you need to create a paper trail as to where the parts came from, as in the donor planes year and model with the airframe serial number". He referenced the 6 parameters that are talked about in the video from Cessna. I asked specifically about the wing tanks. Can I leave the 172A tanks in with the electric fuel senders or do I have to swap out my original tanks with tanks the Manual float gauges? He said "you can.... but now you need to show conformance with the 170B type certificate data. If you can't....then you need a 337 and weight and balance.... much the same as installing a different radio in the panel. Of course now you have to document power source, wiring, gauge installation etc.... basically just copy what was in the 172A and you should be fine using it and the factory wiring diagram as the basis for approval.....but you should just keep it simple and go back with original tanks, in my opinion". There ya have it. Straight from the horses mouth.
hilltop170
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Re: The journey begins. 170B project.

Post by hilltop170 »

If you can get that in writing you won't have to argue the case again in the future, as in every annual from now on.
Richard Pulley
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

Don't necessarily have to get it in writing.....just have to get the work and logbook entry done and signed by an A&P (myself in this case) or an IA if I go the 337 route. It's not something you'd need to re certify at every annual.
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Bruce Fenstermacher
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Re: The journey begins. 170B project.

Post by Bruce Fenstermacher »

Jazasaguma wrote:Don't necessarily have to get it in writing.....just have to get the work and logbook entry done and signed by an A&P (myself in this case) or an IA if I go the 337 route. It's not something you'd need to re certify at every annual.
You are right of course.

What Richard is unfortunately talking about is inconsistency with the FAA and that flows down to mechanics. Here is a scenario, you go to sell your plane and a pre-buy or annual is completed and the mechanic/person performing this doesn't believe you have the authority to do what you did or the IA did. One sale lost might not be a big deal but what happens if most of the people performing this inspection don't believe it's correct and you have a difficult time selling your plane.

And as I assume you don't have an IA, every year you will have to satisfy the IA who does review and certify your airplane. Might not be an issue with your current IA. But will your current IA always be available?

So no one may ever question the paperwork. But I bet there will always be a question. This is I believe, why we see so many 337s needlessly completed or more often, the work not performed at all. And why the experimental category is so popular. If this FED is willing to put out his guidance, he shouldn't have any issue signing off on a 337 following it. At the very least a memorandum of his guidance. Very few FEDs will question another FED and the questioning stops. I'm not saying it's right, I'm just stating reality in today's world.
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Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

Yes I can see that scenario playing out with an anal IA who's going for CYA. And your right.....that's the world we live in. But.... upward and onward!!! My airconditioned garage is almost ready and I'll be making a lot of progress soon and will share the glory!! Lol
Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

Goodmorning all. Where is the best place to buy new motor mount for my 170B? I'll need both the "engine to mount" and "mount to firewall". Thanks in advance.
Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

AND WE'RE OFF!!!! The garage has its own central air heat/cool system!!! Already got the firewall stripped and cleaned. Will get the same paint as the exterior. Motor mount battery box and several other parts powdercoated yesterday. Stripping paint now. Fun fun. Lol
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Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

Engine off and partially torn down. It only has 97 hrs since major by a reputable shop with all parts standard. Almost NO west on anything. Mixed emotions about the tear down....but it has to be done for my piece of mind. It's been sitting for 18 years! Still.....it's really clean inside. Crank flange just a little rusty so I'll send it off for yellow tag and fresh cad plating. Will go ahead and put all new bearings, rings, gasketS, seals, etc.... and lap valves. Will cut off starter pinion for Sky Tek starter as well
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Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

Boy.....ya just gotta LOVE powdercoating!!!
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Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

Let the fun begin!!! Now I know why strippers get paid so much money!! Oh wait....that's a whole other subject!! Lol. Suffice to say....not my favorite job in aircraft restoration. But....gotta be done.
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Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

Panel stripped and lower sub panel drilled off. Will make a new, better laid out/organized sub panel that will have all the switches, CBs, engine and environmental controls, slimline comm (+ABS-b txpdr) and glove box in it. Will require only the bad looking wires.
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Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

Finally!!!! The tailwheel was frozen solid!! Couldn't figure out why. Finally got it apart with soaking and gentle tapping/prying. Bead blasted everything and it all passes. Just need to replace the thrust washers and bearings.
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DaveF
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Re: The journey begins. 170B project.

Post by DaveF »

Looking good! Keep up the pics, we love 'em.
Jazasaguma
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Re: The journey begins. 170B project.

Post by Jazasaguma »

Whew!! I was wondering. Nobody was playing airplane with me anymore. Lol!! I enjoy sharing in the hopes that there's someone with a stalled project that doing these just may motivate them to get started again. Life is short. Play hard!!!
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