I'm in year 3 of a Beaver semi flying restoration. The airplane was in Africa when new and then Australia. After that it came to Canada.
Restoration and maintenance was done by large Canadian shop and supposed "experts". Victoria Air Maintenance. I believe it was actually worked on by mechanics school and signed off there?
Yes the last couple annuals were done by the owners IA in Texas also but most of the list below was wrong well before that. I think he just looked and signed it off without doing much of anything.
Nice external looking airplane, nice paint etc. Owner did not get a prebuy based on reputation of shops doing the work and since it was during Covid travel was messed up. I didn't find out about the airplane until after it was delivered.
Video of the airplane here prior to purchase. I think you can hear the cyclic odd noise the engine was making in some of the audio.
https://www.youtube.com/watch?v=xTyf6huPUJo The airplane flew in during 2020 with current annual and I got looking around to see some things were not right. Digging further many things were not right. How it goes, the more you look the more you find.
Just off the top.
#1 intake tube was cross threaded and the lower nut popped off in my hand. Intake was ready to depart.
Fuel tanks were all leaking, Poor weld repairs cracked. Dynaseal washers missing, tanks repaired with fiberglass, duct tape and bondO. Some gaskets missing from fuel sending units and fuel found in the senders. Some fuel lines cut off short with long slip over rubber hoses to make the connections.
Rivets missing from rear spar splice plates both wings. Poor rivet installation other holes, Bent over tails, under bucked etc.
Tailwheel steering components and bushings completely worn out
Wrong brake cylinder parts causing brakes to intermittently not release
Engine way out of time.
Valves way out of adjustment
Every baffle worn out, poor repairs
Cowl latches, pins worn out
Controls out of balance. Rudder and elevator way out!
Cable tensions all incorrect
Corrosion under floor on bulkheads where they contact floors
Poor repairs of baggage bulkhead and corrosion in floor areas
Previously removed home made electric boost pump system and fuel system plumbing routing not corrected. Very old fuel system hoses
Worn aluminum hard lines in belly for fuel and oil system.
Aluminum Tie bar between lower gear leg fittings stretched from hard landing. Extrusion appears necked down in thickness on one end.
No record of NDT test of forward inboard wing attach fittings when cockpit door post replacement was done.
Forward left wing fitting very abused with deep nicks, scratches and marks in wing attach area.
FWD Door posts replaced, new Sealand posts are the wrong length so doors do not close without a lot of effort. Kenmore said new Posts length is to the drawing spec but the airframes vary more than the drawing tolerance allows. By a lot...
Dual G5s installed but wet Vacuum pump and lines still on engine pumping to outside air with open lines.
All fuel tank bay avionics conduits missing. US Repair station Radio shop ran harnesses to rear mounted ADSB and G5 remote compass in rear fuselage through tank bays with no chafe protection and ADEL clamps left loose so wires were chafing on bulkheads.
Pilot and Copilot seat backs cut down lower than standard which lowers the shoulder harness angles to where they would compress your spine in an accident.
Unapproved baggage modifications
Poor skin repairs in upper wing skins. Skins appear torn by snips or piercing and new skins lapped over top
Incorrect aileron pushrod rod ends to flaperon mixer in cabin top
Worn out throttle, prop, mixture rod ends in linkages
Leaking flap hydraulics, air in the system
Very old rotten padded clamps holding hydraulic and fuel lines
Placarded Under floor baggage area in camera port area with no sign of walls on the sides of the baggage area so any baggage placed there can roll into the elevator pushrod and bell crank. During Prior repairs and stringer replacements the baggage sides were never installed.
Incorrect elevator pushrod rigging causing chafing on bulkheads
Oil cooler mounts cut and bent to install larger diameter oil cooler. Oil cooler scoop was still the original diameter so no airflow got to the larger cooler.
Aft bulkhead on fuselage under horizontal tail riveted on off center and fuselage from forward end of horizontal tail riveted with twist to aft bulkhead. To install horizontal tail the rear block was cut on one side and plate added to the other.
Tailwheel vertical tiller installed with tailwheel steering arm drilled off center
All gear fairing nutserts stripped and multiple sizes.
We changed engines. The engine mount was superseded part number and had to be replaced $$$. All fittings and plumbing were a mess and I ended up changing all of it. Carb heat box was a total rebuild.
Exhaust system worn out (tube IDs at slip joints) with a few flanges broken.
Engine dishpan inner stainless parts worn through all the way around. Poor repairs of outer dishpan, Air filter door latches worn out.
Rigging out of adjustment. Not flying hands off. Yoke not centered.
Cabin top upholstery over cabin lights. Hot light bulbs had melted some of it.
Interior screw holes drilled through cabin bulkhead forward vertical extrusions each side of pilot seat area. Rivets missing from same area, Some rivets had been replaced with non structural cherry rivets,
Forward under floor supports missing.
There was more wrong but this is the list that comes to mind.. Places to look.
The hard part is determining what MOD numbers have been installed on any airplane to know what should or should not be there based on the parts books and maintenance manual.
The MOD numbers are factory changes and kits different from STCs.
Then search AD compliance and Verify all STCs installed per the STC instructions.
Some STCs conflict with others. That is tough to sort out.