Hi guys, TB 20 12V, my turn coordinator is very noisy. This noise comes from the bearings. I’m looking for a used one or has someone
a good idea?
Thomas
Buying a used TC is just inviting another failure in the near future. A new item will be cheaper in the long run.
Yes, once they are noisy, they’re on their way out. The DC brush dust gets in the bearings. Look for an AC or brushless version, and buy brand new of you can (I guess unless you’re about to sell the plane!)
Or put in a backup AI such as the GI275
Whilst doing an avionics update we put a refurbished turn co-ordinator in the panel (despite having 2 x GI275) primarily so that limited panel exercises can still be taught. We used https://aircraftinstrumentsltd.co.uk/ who delivered a good service. They will take your old unit in exchange for one that has already been refurbished and correct paperwork is supplied.
I used that firm in 2017 to overhaul a KI256. Took some months to get it back, and without paperwork because they had the “usual arrangement” to use somebody else to print off the forms and that somebody stopped doing it… I use Castleberry in the US for instrument overhauls.
Putting proper AI G5/GI275 seems to be no brainer and way more cheaper & safe than sorting and maintaining a rusty TC? the partial panel can be done with backup AI and/or wet compass as long as you find the right pragmatic examiner 
?
You can keep old TC in panel for compliance or future sale (TC+1st AI+2nd G5 is a good combo) as you will rarely fly on TC in real life: I personally observed that there is an empirical correlation between “parroting all day about partial panel skills on TC” and “chicken out when weather is near ILS minima”, I think having proper secondary AI backup like G5 should cure some of the fear….it’s just like paper map, people who fly circuit & local all the time in familiar places tend to have strong opinions on GPS and will parrot all day on their superior map reading skills, the same thing people who fly in CAVOK, tend to parrot all day about superior TC skills !
way more cheaper
How much is a GI275?
GI275 are about 3k£-4k£ depending if AI and/or HSI, autopilot interface, temperature, manometer
Certified G5 would be 2k£-3k£ and new TC likely near 1k£
(gliding joke), the next after would be “MK IV Yaw String” at 15£ and available in natural wool (red, royal blue, light blue,yellow) and it’s PMA’d, STC’d or TSO’d
Plus installation… plus the GI275 has some pretty significant reliability issues, so replacing the TC with an identical unit is a no-brainer.
