Bendix King Autopilot Service Bulletin 292

[V1VRV2]

How often are you complying with the BK Service bulletin 292 which is an ICA for auto pilot servo inspection once a year or 1000 hrs. It’s quite an expensive SB to comply with ever year and seems like overkill. 

[V1VRV2]

So many Bendix King autopilots installed in Mooneys and no responses? Do I take that as no one is doing inspections?

[Bob - S50]

Got rid of our KFC200.

[MIm20c]

Haven’t complied with that SB. You can probably buy spares for every part of your AP system for pennies on the dollar. I’d go that direction first. 

[carusoam]

6 hours ago, V1VRV2 said:

So many Bendix King autopilots installed in Mooneys and no responses? Do I take that as no one is doing inspections?

Do you know how to get a response?

 

Lets put the document in front of people first...

See if that helps..?

OK... couldn’t find the document...  my search came back to this thread first....

Next best thing was equally detail less...

https://www.duncanaviation.aero/intelligence/2013/May/bendix-king-autopilot-100-150-series-servo-maintenance

So, there is a an annual test... what does it look like..?  
 

If it is getting done on my plane, it would be during the annual...

Best regards,

-a-

[tmo]

11 hours ago, MIm20c said:

You can probably buy spares for every part of your AP system for pennies on the dollar. I’d go that direction first. 

If anyone is looking to unload KFC200 parts for real cheap, I'm interested in items for my spares shelf. Especially that mine is acting up somewhat.

Could also use a 12V electric vacuum setup for cheap, I'm currently using a crude setup based around a removed engine driven vacuum pump and a cordless drill to exercise the KI-256 spare I have.

Edited October 27, 2020 by tmo

[PT20J]

I don't see any reason to comply with the SB. In my limited experience, BK servos are pretty reliable. I'm in the Mike Busch camp of don't mess with stuff if it's working and not mandatory. SBs are not mandatory unless part of an AD, and ICAs are not mandatory except for the limitations section. Pulling working parts out for routine preventive maintenance seems more likely to cause problems than prevent them.

I do lube the trim servo carrier bearing (that frequently gets overlooked) and trim drive chain. Those items are easy to do and minimally invasive.

Skip

[ZuluZulu]

On 10/26/2020 at 4:32 PM, MIm20c said:

Haven’t complied with that SB. You can probably buy spares for every part of your AP system for pennies on the dollar. I’d go that direction first. 

*cough cough shameless plug cough* Make me an offer!

[StevenL757]

1 hour ago, PT20J said:

I don't see any reason to comply with the SB. In my limited experience, BK servos are pretty reliable. I'm in the Mike Busch camp of don't mess with stuff if it's working and not mandatory. SBs are not mandatory unless part of an AD, and ICAs are not mandatory except for the limitations section. Pulling working parts out for routine preventive maintenance seems more likely to cause problems than prevent them.

I do lube the trim servo carrier bearing (that frequently gets overlooked) and trim drive chain. Those items are easy to do and minimally invasive.

Skip

My thoughts exactly.  My BK servos have worked near-perfectly in 22+ years of operation.  Just recently, the pitch trim servo needed OH/exchanged...an isolated incident.  I do comply with SB343 - Trim Carrier Bearing lubrication every annual as Skip @PT20J mentions, but don't spend the $2,400+ yearly to perform SB292.

Steve

[Greg_D]

22 hours ago, StevenL757 said:

My thoughts exactly.  My BK servos have worked near-perfectly in 22+ years of operation.  Just recently, the pitch trim servo needed OH/exchanged...an isolated incident.  I do comply with SB343 - Trim Carrier Bearing lubrication every annual as Skip @PT20J mentions, but don't spend the $2,400+ yearly to perform SB292.

Steve

Do you have any pictures or drawings that show the trim carrier bearing and exactly where/what to lube it with?