Autopilots Central for Century 31?

[whiskytango]

Has anyone sent a Century 31 autopilot to Autopilots Central for repair?  My avionics shop sent mine back to Century to correct a runaway pitch trim problem.  It worked for a few hours, but now will not hold altitude.  I want to keep it alive until a Trio or TruTrak STC arrives and I can get rid of it, but I am losing confidence in the Century factory for repairs.

[INA201]

https://www.bevanrabell.com/

had them rebuild my entire Century 2b  system. 

[chuck459]

I would avoid Autopilots Central.  Maybe they have their personnel problems sorted out by now, but in the year I worked with them, they changed shop managers five times.  There was only one technician that knew anything about a Century 41 and he was simi-retired and only worked part time.  They cost me over $14 dollars and months of down time trying to correct a pitch issue.  They kept my airplane in TUL for six weeks and replaced or overhauled every component in the system that had anything to do with pitch.  They never did fix the problem and eventually stopped returning my telephone calls.  I ended up taking the airplane to the Century factory in Mineral Wells.  The problem turned out to be an intermittent wire inside the attitude gyro which they fixed in a few hours.  They also found loose parts in the belly of my airplane which Autopilots Central had left behind.  What a difference in attitude and knowledge of the Century AP.  If you have a problem with any Century AP,  my recommendation is to take it directly to the factory.

[Mark89114]

12 hours ago, chuck459 said:

I would avoid Autopilots Central.  Maybe they have their personnel problems sorted out by now, but in the year I worked with them, they changed shop managers five times.  There was only one technician that knew anything about a Century 41 and he was simi-retired and only worked part time.  They cost me over $14 dollars and months of down time trying to correct a pitch issue.  They kept my airplane in TUL for six weeks and replaced or overhauled every component in the system that had anything to do with pitch.  They never did fix the problem and eventually stopped returning my telephone calls.  I ended up taking the airplane to the Century factory in Mineral Wells.  The problem turned out to be an intermittent wire inside the attitude gyro which they fixed in a few hours.  They also found loose parts in the belly of my airplane which Autopilots Central had left behind.  What a difference in attitude and knowledge of the Century AP.  If you have a problem with any Century AP,  my recommendation is to take it directly to the factory.

I am not one to bash, but I took my plane to APC as well and not really impressed.  Spent a bunch of money and problem isn't fixed, they blamed it on the last part they couldn't diagnose in house.  

[gacoon]

What was the part yhey blamed it on?

[Piloto]

On ‎7‎/‎29‎/‎2017 at 12:52 AM, whiskytango said:

Has anyone sent a Century 31 autopilot to Autopilots Central for repair?  My avionics shop sent mine back to Century to correct a runaway pitch trim problem.  It worked for a few hours, but now will not hold altitude.  I want to keep it alive until a Trio or TruTrak STC arrives and I can get rid of it, but I am losing confidence in the Century factory for repairs.

I had the same problem. Check your vacuum indication. I found that Century attitude gyros run better at 5.5" Hg. I adjusted the vacuum regulator from 4.5 to 5.5 and now pitch is rock stable.

José

[Mark89114]

5 hours ago, gacoon said:

What was the part yhey blamed it on?

Summary is I had a slight porpoising issue.  They checked the pitch servo and found a noisy tach generator(I think that is the word) replaced that, still same issue, they then tested and blew out all static lines, problem still existed, also tested KI-256 said no issue there, they finally tightened up the pitch trim springs to mooney specs, all that did was make the porpoising slower.  Their final thought was it might be a noisy acceleration sensor in the autopilot control head, which they don't have ability to test.  I still have the problem.  So not impressed with APC.  

 

[Piloto]

18 hours ago, Mark89114 said:

Summary is I had a slight porpoising issue.  They checked the pitch servo and found a noisy tach generator(I think that is the word) replaced that, still same issue, they then tested and blew out all static lines, problem still existed, also tested KI-256 said no issue there, they finally tightened up the pitch trim springs to mooney specs, all that did was make the porpoising slower.  Their final thought was it might be a noisy acceleration sensor in the autopilot control head, which they don't have ability to test.  I still have the problem.  So not impressed with APC.  

 

Exactly my problem, I even cleaned all the connectors contacts. What finally fix the problem was increasing the vacuum to 5.5"Hg.

José

[carusoam]

Mark,

Which AP Do you have in your R?

Best regards,

-a-

[Mark89114]

5 hours ago, carusoam said:

Mark,

Which AP Do you have in your R?

Best regards,

-a-

KFC 225

[LANCECASPER]

13 hours ago, Mark89114 said:

KFC 225

Where are you located?

[Mark89114]

1 hour ago, LANCECASPER said:

Where are you located?

I am all over the place....plane is hangared in Fort Smith, AR, but also spend a lot of time in Richmond VA.

[LANCECASPER]

They guys at Central Texas Avionics in Georgetown TX are excellent on King Autopilots. I've had personal experience with them on a 2000 Ovation I had - they rebuilt a trim switch and could have easily padded the bill, but they didn't. They spent a couple hours also on a KFC150 on a '97 Encore that I had and it flew much more precisely after that. They have all of the King test equipment and more importantly, the knowledge to go with it. From Fort Smith you are only 325 nm from Georgetown (KGTU) and their fuel is only $3.65 a gallon. It might be worth it to have them take a look.

[whiskytango]

On 1/11/2018 at 11:49 PM, Piloto said:

I had the same problem. Check your vacuum indication. I found that Century attitude gyros run better at 5.5" Hg. I adjusted the vacuum regulator from 4.5 to 5.5 and now pitch is rock stable.

José

I sent the C31 back to Century.  They told me that the altitude transducer was defective, and the part is no longer manufactured.  They sent the C31 back tagged INOP.  Since then I have been looking for another C31 that I can use as a parts source.

[Piloto]

10 hours ago, whiskytango said:

I sent the C31 back to Century.  They told me that the altitude transducer was defective, and the part is no longer manufactured.  They sent the C31 back tagged INOP.  Since then I have been looking for another C31 that I can use as a parts source.

Check for pitch holding on no ALT hold mode. If the pitch changes then you have an attitude gyro problem that also shows on ALT hold. The altitude pressure transducer has a heater coil that when defective it causes small altitude changes.

José

[whiskytango]

3 hours ago, Piloto said:

Check for pitch holding on no ALT hold mode. If the pitch changes then you have an attitude gyro problem that also shows on ALT hold. The altitude pressure transducer has a heater coil that when defective it causes small altitude changes.

José

The problem is that when I push the ALT button, nothing happens at all, and the computer doesn't display ALT on the panel.  Pitch remains whatever it was prior to pushing ALT. It seems that the altitude hold circuit does not even attempt to operate with the faulty transducer. 

[Piloto]

4 hours ago, whiskytango said:

The problem is that when I push the ALT button, nothing happens at all, and the computer doesn't display ALT on the panel.  Pitch remains whatever it was prior to pushing ALT. It seems that the altitude hold circuit does not even attempt to operate with the faulty transducer. 

On normal operation ALT light will not light up just after power up until the transducer is warm enough for operation. The manual says to perform the test function before flight. I never do it and it works fine but try it to see if it makes a difference.

[Piloto]

Check the panel shock mounts. If they are broken the panel may vibrate causing the attitude gyro to cause the autopilot to change pitch.

José 

[whiskytango]

1 hour ago, Piloto said:

Check the panel shock mounts. If they are broken the panel may vibrate causing the attitude gyro to cause the autopilot to change pitch.

José 

José, 

I tried the test function and the panel shock mount suggestions.  No joy - still no ALT hold.  My next move is to take the computer out and see if I can get the part number off the transducer.  There has to be another one of these out there somewhere.

I had a C41 autopilot in a K model I owned about 15 years ago.  I never had any problems with it and it was super accurate.  The C31 has had nonstop problems since I bought my current K model about a year ago.  

 

[LANCECASPER]

56 minutes ago, whiskytango said:

José, 

I tried the test function and the panel shock mount suggestions.  No joy - still no ALT hold.  My next move is to take the computer out and see if I can get the part number off the transducer.  There has to be another one of these out there somewhere.

I had a C41 autopilot in a K model I owned about 15 years ago.  I never had any problems with it and it was super accurate.  The C31 has had nonstop problems since I bought my current K model about a year ago.  

 

A trip to Century Autopilots in Mineral Wells TX might be worth it. The fuel there is pretty cheap for the return trip. http://airnav.com/airport/KMWL

[Piloto]

If you have access to the maintenance manual you can get the pressure transducer part number. Search by the p/n on the internet. Digi-Key has a bunch of these transducers that may fit.

José 

[Vlakvark]

On 1/12/2018 at 10:21 PM, Piloto said:

Exactly my problem, I even cleaned all the connectors contacts. What finally fix the problem was increasing the vacuum to 5.5"Hg.

José

Where are all the connectors to clean ore how do we clean them Mine now disingage as soon a I turn it on. How and where do we spray the connectors and amp at the Hg. Im down to no more nerves flying it. Handfly at 17K cause autopilot flashes AP and then nothing. Drive me nuts. Please help. Gotta flight to Des Moines

Edited June 4, 2018 by Vlakvark