agjolly

I have reseated connections on the radio coupler several times. I will try reseating all connections that I can find before next flight. I'm having trouble believing that my AI and DG are suspect since it flys great in Wing Level (only) or HDG mode. It only acts up when in the NAV modes. What were the symptoms in your plane that the AI overhaul fixed? Thanks for the reply!

It does the same thing on all NAV modes (even BC) and both sources (G430 and KX170B). I haven't tried it with the NAV sources off, I will do this next flight. I have reseated the connections on the coupler several times. I haven't reseated the connections on the source relay (assuming it has connections and not directly wired, I will try this also). I do have a NAV 1/2 switch but it's a booger to get to. This will be a near future check if the other checks don't provide a fix. Thanks for the feedback.

I am having problems with my Century IIB (single axis) autopilot. It works well in HDG mode. When I switch the radio coupler to any of the NAV modes the autopilot initiates an immediate right turn even with the CDI deflected left. Has anyone else had this problem? I was reviewing the ground/flight calibration procedure in the Century II&III manual (pages attached). I can understand the instructions all of the way through except in one area. It seems there is a step missing around paragraph (10) of page 6-5. I would think the radio coupler would need to be in one of the NAV positions (probably OMNI). It appears from the procedures that the radio coupler is in HDG mode at this point and I believe it would just be tracking heading and the left deflected CDI wouldn't have any effect on the heading computation of the autopilot. Am I correct in thinking that the procedure should include OMNI (or some other NAV) mode at this point? If there is anyone that has experience with the Century IIB calibration, I would welcome your input. Anyone else that would have any ideas, I would welcome those also.

Piloto, The supply to the gauges is roughly 12vdc. The 2vdc is on the signal wire going to the sending unit when the wire is disconnected. With the wire connected to the sending unit it is lower than 2vdc. I had already cycled the CB and didn't see any improvement. The voltage stayed roughly the same after cycling. Thanks for the reply.

Both of my pressure gauges (oil and fuel) are reading low (about half). We (my A&P and I) put a mechanical gauge in the circuit and verified the electrical gauge readings are low. We've checked wiring connections, power and ground. I've checked the sending units and not sure the resistance is correct. The sending units doesn't appear to be the original ones. I'm concerned that they may have been replaced with the wrong resistance units. The fuel pressure gauge is 0-30psi The oil pressure gauge is 0-100psi Can someone tell me: 1) What should be the resistance ranges of the sending units? 2) What should be the voltage on the wire with it disconnected from the sending unit? I'm reading about 2 vdc. This is a new plane to me and I have the service manuals ordered but haven't received them yet. Any help or ideas are welcomed!

Contemplating painting my 1978 M20J (original paint). Looking for some recent experience and results. Please post with who you used, cost, results, pics, recommendations, contact info, location, or any other pertinent info, etc. Thanks!