Jim P
Well Known Member
So for background, see this thread; https://vansairforce.net/community/showthread.php?t=197140&highlight=EGT
I'd spent several hours continuing to troubleshoot this #4 EGT issue. Runs fine at idle, goes high as power is applied. To finish out troubleshooting:
1) I did confirm EGT peaks with the others
2) Swapped out spark plug harness
3) Did engine run, still had the problem!
Normally doing a maintenance run I'll watch the engine monitor as power comes up, but I happened to look over the nose and noticed some droplets spitting out. What the.....
Shut down, confirmed all the fuel injector connections were tight and fired it up again. Pushed up the power to 1800, and I'm seeing a lot more droplets. Shut it down and check engine again. This time, looking at #4 supply line at the spider, there's a small crack!
Cracked Line on OneDrive: https://1drv.ms/u/s!Al5IppCB40wPhKkIv7S-yUVppD2ZTQ
After pulling the line, I bumped the end and basically the spider end fell off! Engine has 675 hrs TTSN, but I figure this was either a manufacturing defect or work hardened. The line is secured in two places between spider and injector. When doing the flow test, I figure that without the injector, there was little back pressure, so flow testing was OK, so that didn't catch this problem.
Now to find a new part in the next couple days! If anyone knows the source for those lines, please let me know. They don't show up on Precision Airmotive site.
I'd spent several hours continuing to troubleshoot this #4 EGT issue. Runs fine at idle, goes high as power is applied. To finish out troubleshooting:
1) I did confirm EGT peaks with the others
2) Swapped out spark plug harness
3) Did engine run, still had the problem!
Normally doing a maintenance run I'll watch the engine monitor as power comes up, but I happened to look over the nose and noticed some droplets spitting out. What the.....
Shut down, confirmed all the fuel injector connections were tight and fired it up again. Pushed up the power to 1800, and I'm seeing a lot more droplets. Shut it down and check engine again. This time, looking at #4 supply line at the spider, there's a small crack!
Cracked Line on OneDrive: https://1drv.ms/u/s!Al5IppCB40wPhKkIv7S-yUVppD2ZTQ
After pulling the line, I bumped the end and basically the spider end fell off! Engine has 675 hrs TTSN, but I figure this was either a manufacturing defect or work hardened. The line is secured in two places between spider and injector. When doing the flow test, I figure that without the injector, there was little back pressure, so flow testing was OK, so that didn't catch this problem.
Now to find a new part in the next couple days! If anyone knows the source for those lines, please let me know. They don't show up on Precision Airmotive site.
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