Navomatic 400

[cessnadriver]

WSLADE2.
The shop is Mayday autopilot/avionics, Grand Rapids, MI. SHOT means the drive transistors? and both electric motors have to be send out for rebuild at $2500-$2800 each! Also not really related both AI and DG have to be overhauled. The shop was quoting Mid-continent about $5500 for those, although I found a shop, basically across the street from Mid-continent that will overhaul both for about $1200 AQI is the name. I had Mayday send the instruments to AQI. What started this whole ordeal, I had sent Mayday my original 400 and a newer 400(not sure the year-but around a 1967 model) that I bought from a SOAPA member. The tech called me yesterday and told me that the two 400 I sent him are not compatible, hoping he could use parts from both to build-up one. I told him that Autopilot Central had quoted me $1700 each for the servo rebuild, and he's going to call them on Monday? A member just wrote to tell me he removed his 400 and is willing to GIVE me his components, arranging shipping as we speak!!! As for moving on that's your decision, but I'm tell you if your 400 is working, I'D KEEP IT, until the TRU-TRAC generation comes to Skymaster!
Hope this info helps.
Regards, BILLS

[wslade2]

Thank you!! That is extremely helpful information. My control head (resolver) won't allow the course direction to turn and just turning on the autopilot makes it go immediately into 30 degree bank. My servos were almost locking my controls and had to disconnect them to give the controls safe movement without wrestling them. So I know my servos and control head need overhaul (Autopilots Central wasn't sure they could do anything with control head when I spoke to them over phone), and might as well count on panel instruments overhaul. Then heaven forbid central computer work and chasing wiring. That's a big chunk of a new system, specifically S-tec. 337 not certified on the new garmin but could request and wait. Or wait for others as you mentioned.
The good news you report is sounds like service is still available for the straight 400. I did buy a system out of a 310 that has a lot of similar parts.

[Learjetter]

Data point: spring 2021: Major Florida avionics shop quoted me $39,000 to install STEC 55x with auto trim.

[Dr.Dan]

We need to keep hounding Garmin for the gfc500.
Please garmin?

[YankeeClipper]

"We need to keep hounding Garmin for the gfc500.
Please garmin?"

Aye.

[JAG]

About every 6 months I send Garmin a note. I keep see them developing STC's for aircraft types and fleets smaller and less expensive than ours - and I make sure I point this out. If people keep registering their interest for their new digital APs, we may get some action.

Jeff

[YankeeClipper]

Yeah. I'm probably overdue to send them a nag myself.

[chrisb]

Originally Posted by YankeeClipper

"We need to keep hounding Garmin for the gfc500.
Please garmin?"

Aye.

I'm hounding :-)
Along with the EIS TXI

[cessnadriver]

WSLADE2.
An update, I had to replace my AI and DG instruments due to a 4-6 week back-order on the bearings, The shop offered new instruments, and yes compatible replacements for the 400 autopilot, for $300 over the overhaul! Still having servo problems, having gifted servos from a SOAPA member checked by Mayday Avionics. If these don't work I'll have to go with (hopefully) serviceable servos from Preferred Airparts at $1700 for both. Or the $2500-$2800 rebuild per servo? I thought I found a new autopilot, S-Tech 3100, but it's not authorized for the C337! I'll keep you updated, and thanks for your support.
Regards.
BILLS

[patrolpilot]

Originally Posted by Learjetter

Data point: spring 2021: Major Florida avionics shop quoted me $39,000 to install STEC 55x with auto trim.

That is much the same from the two independent shops I've checked with.

Garmin, my avionics guy, asked his Garmin friend and was told the C337 wasn't going to happen, not enough airframes to justify the certification expense.