Flying_Monkey
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- Joined
- Sep 22, 2014
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During runup today I noticed that the JPI 830 was showing 12.1 V on my battery and not the usual 13.7 through 14.0 V. The alarm on the JPI briefly went on for BATT as the voltage dipped below 12. The Load meter was showing zero and cycling the alternator side of the master switch made it move a tiny bit for a brief moment- almost imperceptible. No circuit breakers were popped. I turned on all strobes and lights and load meter did not move. I taxi'd back to the hangar and during taxi it seemed like the engine stumbled at one point but I can't be sure of throttle position and fuel flow position. I think it stumbled when I started going uphill which could cause a reduction in RPM (I think).
In any case I got back to the hangar to pull the cowl off. When I stepped out of the plane I noticed it smelled different than usual. I pulled the cowl off and there seemed to be some grey smoke but I'm not sure where it was coming from. The alternator belt is intact.
The only other thing I noticed was this spot on the firewall. Not sure what the tube coming out is from - (maybe the vacuum pump?) and if this discharge is normal. Pics attached. Not sure if it is related. I circled the spot which seems fresh, the tube and what it is attached to.
Left a message for my A&P but in the meantime I thought I'd check in here to see if anyone could lend any advice.
I am including the JPI log from my previous flight. I noticed the VOLTage drops in the last minute and a half of the flight and right around this time there is a departure of the #4 EGT (and #1). It seems too distinct to be coincidental. This is around the 1:40 mark. This appears to be exactly AT touchdown because the ALT levels off at about field elevation in this exact moment. The landing was uneventful (definitely not a hard landing at all). So it seems like SOMETHING happened right around this time. Any thought are greatly appreciated!
https://www.savvyanalysis.com/flight/1162499/7dfd445e-d3e2-427b-b1f1-1fe68dc2f527
In any case I got back to the hangar to pull the cowl off. When I stepped out of the plane I noticed it smelled different than usual. I pulled the cowl off and there seemed to be some grey smoke but I'm not sure where it was coming from. The alternator belt is intact.
The only other thing I noticed was this spot on the firewall. Not sure what the tube coming out is from - (maybe the vacuum pump?) and if this discharge is normal. Pics attached. Not sure if it is related. I circled the spot which seems fresh, the tube and what it is attached to.
Left a message for my A&P but in the meantime I thought I'd check in here to see if anyone could lend any advice.
I am including the JPI log from my previous flight. I noticed the VOLTage drops in the last minute and a half of the flight and right around this time there is a departure of the #4 EGT (and #1). It seems too distinct to be coincidental. This is around the 1:40 mark. This appears to be exactly AT touchdown because the ALT levels off at about field elevation in this exact moment. The landing was uneventful (definitely not a hard landing at all). So it seems like SOMETHING happened right around this time. Any thought are greatly appreciated!
https://www.savvyanalysis.com/flight/1162499/7dfd445e-d3e2-427b-b1f1-1fe68dc2f527
