major fuel probe related issue -- need help
Posted: Wed May 15, 2019 4:54 pm
Hello all,
I am experiencing a major issue that has more or less grounded my DA40 for the past 5-6 months, and resulted in the R/H fuel probe being replaced three times. At the outset (in late November), the plane has an intermittent R/H fuel gauge indication (occasional red-X). As you can imagine, not being able to find the root cause has been exceedingly frustrating, and I am turning to the forum to see if others have experienced the same and if so what was the eventual fix.
Here is the quick write-up from my mechanic:
The original probe was intermittent red "X". We replaced the probe with new 1/14/19, 2199.6.
The first replacement probe was in service until 1/25/19, 2201.4 (1.8 hours), where it became out of range. We found R/H static dischargers INOP based on suggestion from Neil Grant. Replaced both dischargers with new. Replaced probe with new.
The second replacement probe was in service until 3/27/19, 2215.8 (14.4 hours), where it became out of range. We tested bonding / static systems and found no fault. Probe replaced with new.
The third replacement probe was in service until 4/30/19, 2228.2 (12.4 hours). The probe was tested and found to have no output. Wiggling the wire was able to produce an output around 11 hertz, but only momentarily. We were not able to reproduce any hertz output after that. Bonding and static discharge systems normal.
Mechanic thoughts: The original probe was intermittent, but each time it was tested it was found within range. It was replaced based on experience, we encountered the same intermittent failure on another DA40 and replacing the probe solved the issue. Every probe subsequently installed has failed in a different way; two have become out of range and now the last one has no output. If the argument was made that the airframe is taking out the probes, why isn't the failure the same each time? Why was the original probe intermittent, but never out of range? More troubling, why is the current probe hard failing in a way that seems so mechanical?
Thank you all for attention to this-
Arpad
I am experiencing a major issue that has more or less grounded my DA40 for the past 5-6 months, and resulted in the R/H fuel probe being replaced three times. At the outset (in late November), the plane has an intermittent R/H fuel gauge indication (occasional red-X). As you can imagine, not being able to find the root cause has been exceedingly frustrating, and I am turning to the forum to see if others have experienced the same and if so what was the eventual fix.
Here is the quick write-up from my mechanic:
The original probe was intermittent red "X". We replaced the probe with new 1/14/19, 2199.6.
The first replacement probe was in service until 1/25/19, 2201.4 (1.8 hours), where it became out of range. We found R/H static dischargers INOP based on suggestion from Neil Grant. Replaced both dischargers with new. Replaced probe with new.
The second replacement probe was in service until 3/27/19, 2215.8 (14.4 hours), where it became out of range. We tested bonding / static systems and found no fault. Probe replaced with new.
The third replacement probe was in service until 4/30/19, 2228.2 (12.4 hours). The probe was tested and found to have no output. Wiggling the wire was able to produce an output around 11 hertz, but only momentarily. We were not able to reproduce any hertz output after that. Bonding and static discharge systems normal.
Mechanic thoughts: The original probe was intermittent, but each time it was tested it was found within range. It was replaced based on experience, we encountered the same intermittent failure on another DA40 and replacing the probe solved the issue. Every probe subsequently installed has failed in a different way; two have become out of range and now the last one has no output. If the argument was made that the airframe is taking out the probes, why isn't the failure the same each time? Why was the original probe intermittent, but never out of range? More troubling, why is the current probe hard failing in a way that seems so mechanical?
Thank you all for attention to this-
Arpad