Tom Baker Posted June 26 Report Share Posted June 26 I doubt that it is heat from the engine side of the firewall. If it were, it would be blazing hot in the airplane, especially in the summer. Also remember that this was also about the same time that they were switching from leaded to non lead solder in the EU. This also led to issues with the ignition modules. Quote Link to comment Share on other sites More sharing options...
FlyingMonkey Posted June 26 Author Report Share Posted June 26 57 minutes ago, Tom Baker said: I doubt that it is heat from the engine side of the firewall. If it were, it would be blazing hot in the airplane, especially in the summer. Also remember that this was also about the same time that they were switching from leaded to non lead solder in the EU. This also led to issues with the ignition modules. Excellent points, this all makes sense! Quote Link to comment Share on other sites More sharing options...
FlyingMonkey Posted July 9 Author Report Share Posted July 9 Update: I re-soldered the four points on the relay board where cracks were noted on the through pins. I *really* wanted to use hot pink nail polish to reseal the board for Tom, but realized clear would let me more easily see if they cracked again so practicality prevailed. I also tweaked the potentiometer on the board to provide a slightly higher output voltage to the flaps to give them a little more authority. They *might* feel a hair stronger, but if so it's tiny. The board is back in and I've put about six hours on it, so far so good. Cracked solder points seems to be the most common answer for those struggling with the same flaps symptoms I had. Thanks everybody for the help. Quote Link to comment Share on other sites More sharing options...
Towner Posted July 9 Report Share Posted July 9 Congratulations! Thanks to the forum, numerous areas to trouble shoot have been mentioned and give us several places to look, but I agree that the solder issues seems to be the most common problem. Quote Link to comment Share on other sites More sharing options...
FredG Posted July 10 Report Share Posted July 10 Excellent outcome. So satisfying to find a problem and fix it. Quote Link to comment Share on other sites More sharing options...
BMcCand - N248CT Posted August 8 Report Share Posted August 8 I've joined the intermittent flaps club. 2006 CTSW. I'd greased the lead screw in the past. The latest time if failed I wiggled the wires into the motor, no help. In manual up/down mode I could see the LED's in the display and hear relays clicking. Landed and flew back at -6. Seems the likely fault is the relay board on the firewall. Reading this thread left questions - 1. Are the wires into the board marked ? 2. should I try the mounting screws first to see if rivnut spins? 3. if rivnut fails, what next ? wait until engine pull ? 4 what's the best way to get the hot glue off terminals? thanks to folks for all the info so far. Quote Link to comment Share on other sites More sharing options...
FredG Posted August 8 Report Share Posted August 8 I do not recall the wires being marked in any useful way. I used colored sharpie markers to ensure that I could get the wires back on to the correct terminals. I took photos once the wires were marked and before I removed them so that I could be certain about their location when re-installing. I removed the mounting screws and had one rivnut spin. I ended up grabbing the rivnut with pliers on the engine side of the firewall. It was a serious pain in the... I ended up destroying the hole that the rivnut was in and made an oversized carbon fiber plate for mounting the board (with rivnuts I set with my own tool) and attached that plate to the cabin side of the firewall with RTV silicone. I think I simply scraped the hot melt glue off the screw heads of the terminals. If you remove the wires with the board in place a long shank screwdriver will be very helpful. I used a grinder to shape the screwdriver blade for a good fit to the terminal screws. Quote Link to comment Share on other sites More sharing options...
FlyingMonkey Posted August 9 Author Report Share Posted August 9 7 hours ago, BMcCand - N248CT said: I've joined the intermittent flaps club. 2006 CTSW. I'd greased the lead screw in the past. The latest time if failed I wiggled the wires into the motor, no help. In manual up/down mode I could see the LED's in the display and hear relays clicking. Landed and flew back at -6. Seems the likely fault is the relay board on the firewall. Reading this thread left questions - 1. Are the wires into the board marked ? 2. should I try the mounting screws first to see if rivnut spins? 3. if rivnut fails, what next ? wait until engine pull ? 4 what's the best way to get the hot glue off terminals? thanks to folks for all the info so far. You'll have to look at your setup, but my wires were marked 1 through 7, left to right with tabs on each wire. Getting the glue/sealant off the terminals is the hardest part of the operation. I used a tiny eyeglass screwdriver and just patiently scraped and dug around it. Probably took an hour total and I lost quite a bit of skin. I thought about trying to soften it up with a heat gun on low, but I just didn't want to chance putting that much heat into the relay board. I was able to get to the nuts on the engine side of the firewall, reaching up above where the heater box is. They are not hard to get to, and I have pretty big hands. I did them myself with some effort, but it helps to have a second person to hold the nuts in place while you work the screws. Quote Link to comment Share on other sites More sharing options...
BMcCand - N248CT Posted August 9 Report Share Posted August 9 Andy, thanks for the tips. I've been poking at the glue with a 1/8 screwdriver, slow going. Looking carefully at the firewall under the air filter housing, it appears mine was done with bolts and nuts, not rivnut. So I'll get an assistant with the unbolting. I had expected fasteners to be covered by the firewall blanket but they are not. Wires are indeed labeled, and distinguished by colors on the 3 terminal connector. I'll need the inspection scope to read the labels, and will be sure to remove one at a time. Bill Mc. Quote Link to comment Share on other sites More sharing options...
BMcCand - N248CT Posted August 19 Report Share Posted August 19 Sorry to go quiet on the topic. I finally got the plane together again today. Ground check works, but have not flown yet. Hard to tell if an intermittent is fixed! The first flap movement each day was slow and groaning. Today it worked well. The glue removal over the terminals took patient picking and screwdriver turning. While there were labels they were not useful. Just turning to make the label face the camera would wipe off the ink. I took a bunch of pictures, and wires were unique enough to keep track. I took off the air intake and had an assistant help with the 7mm wrench at the firewall, no trouble there. On bench inspection, I didn't see any solder issues. I touched up the 6 form C relay contacts, then bench tested with a light bulb. (should have tested first but didn't) Thanks to everyone for helpful advice. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.