EdFred
Taxi to Parking
TL;DR: Manufacturer mislabeled leads causing a bunch of extra travel costs and work to be done on the plane that should have never happened.
Full story:
So, I bought a (manufacturer withheld) engine analyzer that was installed on my Comanche (O-540) by my A&P just before the Kentucky Dam Fly-In. Flew it there, no issues. While there, the #2 EGT shows erratic readings, bouncing from 1400 EGT to 200, to 1300, to 600, to 1400, to 80, to 1250, etc. Call my A&P and figure it is most likely a loose connection on the probe. Unable to make the fix at the fly-in I ignored it until I got back home. I redid the connection and still had the bouncy issues with it. So, I disconnect #2 and connect it to the #4 EGT channel, and the #4 probe to the #2 channel. The problem follows the probe, and now at this point it doesn't register any temp other than ambient. Talk to the factory, test it with a multi-meter and get an open line on the resistance test, they send a replacement under warranty and I install it. Boom, perfect. Rock solid readings.
Take my plane up the next day and now the #3 CHT is bouncing the same way the number #2 EGT was. "MF'er!" was my initial response. Land the plane check, the connections on the #3 CHT. All solid. But, just to be sure, I disconnect and reconnect the probe. Still have bounciness, 270...60...320...80...310...100...300...60. More expletives follow. Call the factory. They are sure it has to be a loose connection, because they don't see the CHT probes go bad. OK, back out to the airplane and I connect the #3 probe to the #1 channel, but I don't have enough wire to connect #1 probe to #3 channel. No big deal, I know #1 is good, will just see if the problem follows the probe. So, I have nothing connected to the channel for cylinder number 3, and I start the engine. Cylinder number 1 has a solid reading, with no bounciness, I start to curse because now it looks like it has to be a wiring issue behind the *&$^%#! *#$&#^&*! panel. Except, the #3 CHTs are also rock solid and agree with cylinders 1, 2, 5, and 6. Number 4 indicates as dead. More cursing.
I text my A&P to let him know he hooked the probes up wrong. Then realized that, no, he didn't. All of the EGT and CHT leads were labeled from the factory. So all that needed to be done on install was connect the correct probe to the correct wire and it should all be well. I checked the lead labels and sure enough, it said #3 was connected to #3 and #4 was connected to #4. Mislabeled at the factory. More expletives. Well what the hell else is labeled wrong? So I start the engine up, get everything warm, shut down, and disconnect and reconnect every probe one at a time to make sure that everything is going to the correct cylinder, because imagine the pain in the ass it would be trying to diagnose a cylinder problem when they aren't connected right. Well, all the EGTs are connected correctly, and the CHTs on 1, 2, 5, and 6 are correct. I guess 83.3% success is a B (maybe a B-), right?
So, I go through the process of de-cowling the airplane, carefully cutting all the zip ties, undoing all the Adel clamps, pulling the wire labeled #4 from the left side of the engine and re routing it all the way around to the right side of the engine. Relabel the lead. Do the same thing for #3. Connect the correct #4 to #4 and leave #3 open just to make sure, and I get readings on 1, 2, 4, 5, and 6 with 3 being dead. OK, good. Reconnect #3, zip tie and clamp everything back together. It's below minimums at the field so I pull it out of the hangar and run it to 2000+ RPM and there's no bounciness on any channels, EGT or CHT. Pull the plane back in, re-cowl, collect all my tools and leave. I most likely disturbed the connection on cylinder 4 when I was swapping channels on the 2 and 4 EGT probes, and by pure luck/accident discovered the 3 to 4 and 4 to 3 issue. It only took 8-10 hours of trouble shooting and wire rerouting, (not including the time on the initial bad #2 probe diagnosis and fix) a tank and a half of gas in the truck going out to the airport 4 straight nights after work, along with one extended lunch hour to finally get everything the way it's supposed to be.
So all that being said, if you knew about this as the manufacturer, what would to do make things right with a customer, and as a customer that had to deal with all of this would you expect the manufacturer to make things right with you?
Full story:
So, I bought a (manufacturer withheld) engine analyzer that was installed on my Comanche (O-540) by my A&P just before the Kentucky Dam Fly-In. Flew it there, no issues. While there, the #2 EGT shows erratic readings, bouncing from 1400 EGT to 200, to 1300, to 600, to 1400, to 80, to 1250, etc. Call my A&P and figure it is most likely a loose connection on the probe. Unable to make the fix at the fly-in I ignored it until I got back home. I redid the connection and still had the bouncy issues with it. So, I disconnect #2 and connect it to the #4 EGT channel, and the #4 probe to the #2 channel. The problem follows the probe, and now at this point it doesn't register any temp other than ambient. Talk to the factory, test it with a multi-meter and get an open line on the resistance test, they send a replacement under warranty and I install it. Boom, perfect. Rock solid readings.
Take my plane up the next day and now the #3 CHT is bouncing the same way the number #2 EGT was. "MF'er!" was my initial response. Land the plane check, the connections on the #3 CHT. All solid. But, just to be sure, I disconnect and reconnect the probe. Still have bounciness, 270...60...320...80...310...100...300...60. More expletives follow. Call the factory. They are sure it has to be a loose connection, because they don't see the CHT probes go bad. OK, back out to the airplane and I connect the #3 probe to the #1 channel, but I don't have enough wire to connect #1 probe to #3 channel. No big deal, I know #1 is good, will just see if the problem follows the probe. So, I have nothing connected to the channel for cylinder number 3, and I start the engine. Cylinder number 1 has a solid reading, with no bounciness, I start to curse because now it looks like it has to be a wiring issue behind the *&$^%#! *#$&#^&*! panel. Except, the #3 CHTs are also rock solid and agree with cylinders 1, 2, 5, and 6. Number 4 indicates as dead. More cursing.
I text my A&P to let him know he hooked the probes up wrong. Then realized that, no, he didn't. All of the EGT and CHT leads were labeled from the factory. So all that needed to be done on install was connect the correct probe to the correct wire and it should all be well. I checked the lead labels and sure enough, it said #3 was connected to #3 and #4 was connected to #4. Mislabeled at the factory. More expletives. Well what the hell else is labeled wrong? So I start the engine up, get everything warm, shut down, and disconnect and reconnect every probe one at a time to make sure that everything is going to the correct cylinder, because imagine the pain in the ass it would be trying to diagnose a cylinder problem when they aren't connected right. Well, all the EGTs are connected correctly, and the CHTs on 1, 2, 5, and 6 are correct. I guess 83.3% success is a B (maybe a B-), right?
So, I go through the process of de-cowling the airplane, carefully cutting all the zip ties, undoing all the Adel clamps, pulling the wire labeled #4 from the left side of the engine and re routing it all the way around to the right side of the engine. Relabel the lead. Do the same thing for #3. Connect the correct #4 to #4 and leave #3 open just to make sure, and I get readings on 1, 2, 4, 5, and 6 with 3 being dead. OK, good. Reconnect #3, zip tie and clamp everything back together. It's below minimums at the field so I pull it out of the hangar and run it to 2000+ RPM and there's no bounciness on any channels, EGT or CHT. Pull the plane back in, re-cowl, collect all my tools and leave. I most likely disturbed the connection on cylinder 4 when I was swapping channels on the 2 and 4 EGT probes, and by pure luck/accident discovered the 3 to 4 and 4 to 3 issue. It only took 8-10 hours of trouble shooting and wire rerouting, (not including the time on the initial bad #2 probe diagnosis and fix) a tank and a half of gas in the truck going out to the airport 4 straight nights after work, along with one extended lunch hour to finally get everything the way it's supposed to be.
So all that being said, if you knew about this as the manufacturer, what would to do make things right with a customer, and as a customer that had to deal with all of this would you expect the manufacturer to make things right with you?
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