Pre-buy Checklist

[thailarry]

I am a new member in the process of looking for an "A" or "B' model. Is there a checklist of what to look for on a pre-buy inspection. Thanks for any help. LARRY

[GAHorn]

Wow, Larry! I'm surprised we haven't already created such a list in the MX Library. (Maybe after everyone logs on and helps out with this question I can post one there.)

Things to look for when shopping:

1. Complete logs which include 337's for damage repairs.
2. Corrosion. At wing attach blocks, at horizontal attach, at spars and carry-through. Doorposts , firewall, and gear bulkheads clean and without wrinkles, damage, etc..
3. Rudder cables within rear bulkhead (a blind spot) including at fairleads. All the rest of the flight control cables, including the flap cables from the flap handle up/out. Check the flap lever pawl rivet, per the caution in the MX Library. http://cessna170.org/phpBB2/viewtopic.php?t=2231
4. Tailwheel steering cross-over pulley attach/security in 55 and later models.
5. Aftermarket mod documentation and approvals. (This is a tricky one. There are so many available mods that at first glance might not be evident, such as vacuum pump installations, engine/prop combinations, gear leg change-outs, wheels/brakes other than original Goodyear, instruments/panel changes, "single-piece" windshields, different yokes/handles, alternator conversions, wings from different models installed, tail-pull handles, cowl-steps, fiberglass fairings, vortex generators, etc. They each and every one must have a basis of approval and a form 337 referencing either an STC or with "block 3" approved by the FAA.
6. Non-aviation equipment installed without approval (auto stereos, etc.)
7. Annual Inspection items, (an annual should be performed for YOU as your pre-buy inspection when you are virtually settled on a particular plane, and the title check is clear.)
This will catch most items, as long as you don't accept the current owner's annual inspection as yours, and the inspection is not performed by the last couple of guys who did them.

[Romeo Tango]

Don't be scared off by C170 (non A/B) ragwing models. Unless you have some specific inclination to the A/B (like availability of a particular STC), the original C170 is a fine machine (I'm quite biased) and really not something to be wary of.

RT

[alaskan99669]

I am a new member in the process of looking for an "A" or "B' model. Is there a checklist of what to look for on a pre-buy inspection. Thanks for any help. LARRY

Download this checklist:
http://www.geocities.com/coreyhome/Phot ... re_Buy.doc

[GAHorn]

That's a pretty good checklist...but it overlooks the importance of comparing the engine model, prop model with the aircraft type certificate data sheet. BE CERTAIN those meet the TCDS or have an approval basis for any differences.

[alaskan99669]

That's a pretty good checklist...but it overlooks the importance of comparing the engine model, prop model with the aircraft type certificate data sheet. BE CERTAIN those meet the TCDS or have an approval basis for any differences.

It's a living document, so I'll add those comments tonight. What else should I add?

[GAHorn]

Thanks, Corey!
The danger I see is that a "list" might lead someone to believe that the annual inspection is less necessary. It's not, IMHO.
Unless someone with Inspection Authority testifies/certifies that the airplane meets it's TCDS (or approved substitute) and is considered airworthy, then a potential buyer has not done all that he could to confirm that he's acquiring an airworthy airplane. Include the Item 7 that I suggested in my first post and I'll feel a lot more comfortable with it as a more comprehensive list.

[corefile]

I realize this thread is 8 years old, but was wondering if the link for the checklist which is a dead link now can be found someplace else?

[alaskan99669]

Here is the entire list:

170_Annual_Pre_Buy.doc

(54 KiB) Downloaded 768 times

But when looking over a potential 170 buy, check these items first (these items are in the extensive list above):

Rudder circuit cables between the rudder and the aft bulkhead (inside the tail cone.) These are really hard to get to and so are highly-neglected, and frequently chafed/broken/corroded.

Front spar carry-through and internal wing attach blocks. (These blocks are inside the spar carry-through and the bolt that holds the wing to the fuselage pass through this block.) These suffer from 50 years of age in a high water collection spot.

Front/rear doorposts. These are the main strength of the cabin/fuselage and hard landings and high-speed flap abuse will deform them. The front doorposts are often overlooked by tricycle-gear mechanics, but that is where landing shock-loads are absorbed by the 170.

Be sure to have your inspector check the longeron on which the pilot's right brake master cylinder is attached (pivot point). It is pretty common for them to be cracked or broken. If it's broken, it'll need to have a doubler riveted, which takes ~8 hours.

Take a good look at the door and window hinges. A good negotiating tool if they are bad since it is not an easy fix.

Wrinkles in the skin between the landing gear could indicate bigger problems in the gear box.

Check for cracking and corrosion around the tail spring box.

[blueldr]

If you're relutant to pay an AI to give it an annual and you're competent to do it yourself, I would at least give it an extensive 100 hour inspection.