ryoder Posted November 29, 2015 Report Share Posted November 29, 2015 The wing leveler in my C is not working right. The disconnect button does nothing. The wing leveler is always on while flying rolling the aircraft to the right indefinitely. It will literally go to thirty degrees of bank in ten seconds. I don't recall the leveler rolling th yoke while I taxi and steer with the nose wheel and rudder. I will retest this tomorrow. In the past I had to have almost full left PC trim to keep it straight and level but the leveler did its job, restoring the airplane to straight flight once disturbed. Now it just always goes to the right and I have run out of trim. I read the PC manual and ill retread it tonight. I will probably start by verifying the vacuum hoses are not broken or kinked and are free form obstructions. I will also call Britain once I get more info. My mechanic is unfamiliar with the system so I am going to do some basic troubleshooting first. Quote Link to comment Share on other sites More sharing options...
Mooneymite Posted November 29, 2015 Report Share Posted November 29, 2015 1 hour ago, ryoder said: The wing leveler in my C is not working right. The disconnect button does nothing. The button on the yoke controls the pilot valve. If the button doesn't disconnect the PC, chances are the problem is in one of these components: The yoke button: Check the O-rings. The tubing connecting the button to the pilot valve: check connections at both ends of the tubing and make sure there isn't a leak. The pilot valve: the pilot valve has a diaphragm which may be leaking. It also may have one of the many tiny passages blocked by contaminants. Brittain can re-build the pilot valve, but these things are sitting around in a lot of avionics shops (as people up-grade to newer autopilots) and can be had cheaper than an overhaul. There are many iterations of PC's depending on the year of your plane. Here's a picture of my pilot valve which on my '74 is located on the cockpit side of the firewall, close to where the vacuum line transits the firewall. Quote Link to comment Share on other sites More sharing options...
ryoder Posted November 29, 2015 Author Report Share Posted November 29, 2015 Thanks for the info. Can I buy tubing from Spruce? Which part number? Quote Link to comment Share on other sites More sharing options...
Mooneymite Posted November 29, 2015 Report Share Posted November 29, 2015 4 minutes ago, ryoder said: Thanks for the info. Can I buy tubing from Spruce? Which part number? The tubing is pretty bullet-proof. I'd be surprised if that's your problem unless it's disconnected. I looked at Aircraft Spruce, but couldn't find a listing. Since it's just generic surgical tubing, you can probably find it other places just as easily, maybe cheaper. I'm not sure of the dimensions, but you might check: http://www.ebay.com/itm/like/200917198008?ul_noapp=true&chn=ps&lpid=82 2 Quote Link to comment Share on other sites More sharing options...
ryoder Posted November 30, 2015 Author Report Share Posted November 30, 2015 Hank said his boots were shot and one required taping and one require a rebuild. He said he had the same problem I am having where the plane kept pulling to one side and he had to actively fight against it. I need to know where to find and remove the boots for inspection. Quote Link to comment Share on other sites More sharing options...
MyNameIsNobody Posted November 30, 2015 Report Share Posted November 30, 2015 Weird that the disconnect doesn't work. I get the roll, but if you are releasing air/defeating the system...why would it still have the roll taking place? Brittain has the replacement tubing. Give them a call and discuss what it is doing. They are very knowledgeable and should be able to direct you to the area that is causing the issue. 2 Quote Link to comment Share on other sites More sharing options...
Mooneymite Posted November 30, 2015 Report Share Posted November 30, 2015 38 minutes ago, MyNameIsNobody said: Brittain has the replacement tubing. Give them a call and discuss what it is doing. +1 on calling Brittain. Good folks. Quote Link to comment Share on other sites More sharing options...
Steve65E-NC Posted November 30, 2015 Report Share Posted November 30, 2015 Do not waste time. Call Brittian immediately. They have any parts you need at a fair price. My PC unit was acting up, they gave me simple instructions for bypassing the Pilot Valve. This showed that component to be the only culprit. They rebuild the pilot valve for a fair price with quick turnaround. Over several interactions in the last twenty years, I have never had a better customer service experience. Now, if they would just get stock on my step retract boot so I can remove the black rubber tape patch. The only problem I ever had with tubing was that a previous owner had put a sheet metal screw thru a red or green tube, mid cabin. If you suspect boots, buy a little hand vac pump used for automobile carburator work at Harbor Freight (about $20). It is easy to disconnect and draw down each boot in turn to find which will not hold the vac. 1 Quote Link to comment Share on other sites More sharing options...
Mooneymite Posted November 30, 2015 Report Share Posted November 30, 2015 1 hour ago, ryoder said: Hank said his boots were shot and one required taping and one require a rebuild. He said he had the same problem I am having where the plane kept pulling to one side and he had to actively fight against it. I need to know he to find and remove the boots for inspection. If you can't disconnect the PC, that's a separate issue from pulling. That is a button-pilot valve issue. If it will disconnect, but rolls in one direction, but not the other when engaged, that's probably a servo issue. You have two serovs in the tail cone and one in each wing near the aileron bellcranks. Notice in the picture that electrical tape was added around the edges to prevent leaks....this is probably the issue with a continual roll in one direction. The individual servo boot is leaking, or you've sprung a leak in one of the hard plastic connections (not very likely, but possible). The servos in the tail cone control the rudder and are easy to access. The wing servos require a 5 year old contortionist to apply the fix. A very petite wife may be substituted, but the pay-back will be very high. Quote Link to comment Share on other sites More sharing options...
ShermAv8tor Posted November 30, 2015 Report Share Posted November 30, 2015 2 hours ago, ryoder said: Thanks for the info. Can I buy tubing from Spruce? Which part number? Brittain sells the tubing and couplers to splice if necessary Quote Link to comment Share on other sites More sharing options...
ryoder Posted November 30, 2015 Author Report Share Posted November 30, 2015 1 hour ago, MyNameIsNobody said: Weird that the disconnect doesn't work. I get the roll, but if you are releasing air/defeating the system...why would it still have the roll taking place? Brittain has the replacement tubing. Give them a call and discuss what it is doing. They are very knowledgeable and should be able to direct you to the area that is causing the issue. I know. It's weird. I want to retest it during taxi before calling them. It should roll the yoke when turning during taxi and stop doing that when I pass the disconnect. I think it did neither but need to retest. In the air I couldn't stop it from rolling right without adding some light but continual muscle. Hard to hold a heading like that. Quote Link to comment Share on other sites More sharing options...
N601RX Posted November 30, 2015 Report Share Posted November 30, 2015 It will turn toward the side with the largest leak. A handheld vac pump is the best way to verify all the leaks are fixed. You can connect it to each side indivudally and 30-40 pumps will give you full deflection. It should be able to hold that for a few minutes with only minimal leakage. You can plug the hand pump on the pilots side just above the pilots left knee. Look for the green and red hoses. It may be easier to attach from the outside with the avionics cover removed. The leaks can be further narrowed down by attaching the pump to each run of the Tee in the baggage compartment. One run of the Tee goes to the wing and the other goes to the tailcone. The 2 in the tail cone are easy to see/inspect/remove. The ones in the wing require much more technique. They are located just inside the inspection panel in front of the aileron control rod. 1 Quote Link to comment Share on other sites More sharing options...
Hank Posted November 30, 2015 Report Share Posted November 30, 2015 See the other thread in this forum: Quote Link to comment Share on other sites More sharing options...
Shadrach Posted November 30, 2015 Report Share Posted November 30, 2015 Ryan, has anyone been behind the panel lately? The only issue we've had with our PC was self induced when a hose was clumsily pulled off its fitting behind the pilot side panel bay. As soon as I took off the plane rolled left. Quote Link to comment Share on other sites More sharing options...
ryoder Posted November 30, 2015 Author Report Share Posted November 30, 2015 2 minutes ago, Shadrach said: Ryan, has anyone been behind the panel lately? The only issue we've had with our PC was self induced when a hose was clumsily pulled off its fitting behind the pilot side panel bay. As soon as I took off the plane rolled left. Shadrach, I am glad you mentioned this. I just read it in the other thread. We have done some things like installing a new DG and vacuum pump over the last few months but this next part is kind of embarrassing. When we started the plane, my friend who just got his license had his headset off and mentioned that the plane sounded odd. I took mine off and heard a high pitched air noise like a vacuum leak. It sounded like it was coming from the panel. I pointed to the suction gauge and it had full suction so we did a good run up and took off. I think a hose must have come undone. Where do I look again? Quote Link to comment Share on other sites More sharing options...
Shadrach Posted November 30, 2015 Report Share Posted November 30, 2015 I don't know that your plane is configured exactly as mine. If I were you, I'd start with the lines coming off the TC and work downstream ensuring everything is connected and in good condition. A loud hiss can also be indicative of an Attitude Indicator that is leaking at the face. Quote Link to comment Share on other sites More sharing options...
ryoder Posted December 4, 2015 Author Report Share Posted December 4, 2015 Did some diagnostics today. The pilot valve is working fine, hoses are fine but the aileron boots are completely shot and one rudder boot is not retracting right and is getting hung up. It also doesn't hold vacuum. The other rudder boot is probably so so but I ordered four refurbished boots from Brittain anyway. They will be here on Satuday hopefully. The aileron boots will be a beoch to remove. The rudder boots are simple. 1 Quote Link to comment Share on other sites More sharing options...
MyNameIsNobody Posted December 4, 2015 Report Share Posted December 4, 2015 Glad you got it diagnosed and are on the road to having your PC fully functional. 1 Quote Link to comment Share on other sites More sharing options...
Hank Posted December 4, 2015 Report Share Posted December 4, 2015 Brittain's service is great. A functional PC system is wonderful! I've used mine 11.5 hours in the last two weeks, mostly with the heading bug steering. 1 Quote Link to comment Share on other sites More sharing options...
HRM Posted December 4, 2015 Report Share Posted December 4, 2015 When I did some IFR training with a CFII once he was amazed at my rudder skill. Frankly, with the PC I rarely touch the pedals Quote Link to comment Share on other sites More sharing options...
HRM Posted December 4, 2015 Report Share Posted December 4, 2015 3 hours ago, ryoder said: The aileron boots will be a beoch to remove. You got that right. I flew up to GGG a few years ago with a PC pulling to one side and the master himself replaced an aileron boot on the tarmac in front of his shop hangar. Watching him do it I know I could not begin to R&R one without losing lots of skin and damning my soul many times over with cursing! 1 Quote Link to comment Share on other sites More sharing options...
Shadrach Posted December 4, 2015 Report Share Posted December 4, 2015 Ryan, The more I think about your situation, the more I think that you've misdiagnosed the stuation. I think that the uncommanded roll may be due poor rigging. The previously working PC masked this condition. Now that the PC has failed, the aircraft rolls. You hit the button in an attempt to stop the uncommanded roll and it does nothing because the PC isn't the cause of the roll. There's a good chance you're flying an out of rig bird with an INOP PC. Quote Link to comment Share on other sites More sharing options...
TWinter Posted December 4, 2015 Report Share Posted December 4, 2015 On 12/3/2015 6:55:37, ryoder said: Did some diagnostics today. The pilot valve is working fine, hoses are fine but the aileron boots are completely shot and one rudder boot is not retracting right and is getting hung up. It also doesn't hold vacuum. The other rudder boot is probably so so but I ordered four refurbished boots from Brittain anyway. They will be here on Satuday hopefully. The aileron boots will be a beoch to remove. The rudder boots are simple. Start dieting this week before you try to get the wing servos replaced and keep thinking "skinny hands". It's tight in there.. You will get it eventually and good luck. 1 Quote Link to comment Share on other sites More sharing options...
ryoder Posted December 4, 2015 Author Report Share Posted December 4, 2015 Ryan, The more I think about your situation, the more I think that you've misdiagnosed the stuation. I think that the uncommanded roll may be due poor rigging. The previously working PC masked this condition. Now that the PC has failed, the aircraft rolls. You hit the button in an attempt to stop the uncommanded roll and it does nothing because the PC isn't the cause of the roll. There's a good chance you're flying an out of rig bird with an INOP PC. I'll fix the boots and retest. Rigging looks ok by my eye. Quote Link to comment Share on other sites More sharing options...
Marauder Posted December 4, 2015 Report Share Posted December 4, 2015 Ryan, The more I think about your situation, the more I think that you've misdiagnosed the stuation. I think that the uncommanded roll may be due poor rigging. The previously working PC masked this condition. Now that the PC has failed, the aircraft rolls. You hit the button in an attempt to stop the uncommanded roll and it does nothing because the PC isn't the cause of the roll. There's a good chance you're flying an out of rig bird with an INOP PC. I'll fix the boots and retest. Rigging looks ok by my eye. The rigging problem can be a number of different factors and not just the control surfaces. In my case, I had a gear not fully retracted that created drag. A genius mechanic decided to fix the drag issue by mis-rigging the flaps to compensate. You should verify that drag of flaps or gear isn't causing the roll issue. Sent from my iPad using Tapatalk 1 Quote Link to comment Share on other sites More sharing options...
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