chepburn
Well Known Member
Now that the euphoria has lessened a bit on the first flight, I thought I should share a few things here.
1: We kept the flight time to 20 minutes. Then down again and take stuff off to check for leaks, loose bits etc. This is IMPORTANT.
2: Yes, there was a leak NOT detected during ground run-ups, thus this post.
When the cowl was removed, there was a large run of oil on the lower cowl originating from somewhere at the front of the engine.
Hmm? Prop O-Ring? Front Crank seal? Doubtful but maybe....
I had done ground runs cycling the prop (about .5 hours on the Hobbs) and noticed no leaks anywhere firewall forward. I had one on my gascolater, but I tightened that up and all was OK.
The complacency set in at that point.
Now, the part I didnt know. Cycling the prop isnt really enough of an exercise to check the presurization of the oil return line on the governor.
I have an IO-360 A1B with a Hartzell constant speed prop and rear mounted governor. During baffle fabrication, the return line from the front of the engine back to the governor is removed and attached quite a few times.
I had not torqued the forward B-Nut properly. (And, I broke one of my own rules...the nut wasnt torque-seal marked....RED FLAG there!) It tuned out to be about a 3/4 quart lost for a 20 minute flight. Not good.
I missed it. I am posting this, so someone else doesnt miss it as well.
Chris
1: We kept the flight time to 20 minutes. Then down again and take stuff off to check for leaks, loose bits etc. This is IMPORTANT.
2: Yes, there was a leak NOT detected during ground run-ups, thus this post.
When the cowl was removed, there was a large run of oil on the lower cowl originating from somewhere at the front of the engine.
Hmm? Prop O-Ring? Front Crank seal? Doubtful but maybe....
I had done ground runs cycling the prop (about .5 hours on the Hobbs) and noticed no leaks anywhere firewall forward. I had one on my gascolater, but I tightened that up and all was OK.
The complacency set in at that point.
Now, the part I didnt know. Cycling the prop isnt really enough of an exercise to check the presurization of the oil return line on the governor.
I have an IO-360 A1B with a Hartzell constant speed prop and rear mounted governor. During baffle fabrication, the return line from the front of the engine back to the governor is removed and attached quite a few times.
I had not torqued the forward B-Nut properly. (And, I broke one of my own rules...the nut wasnt torque-seal marked....RED FLAG there!) It tuned out to be about a 3/4 quart lost for a 20 minute flight. Not good.
I missed it. I am posting this, so someone else doesnt miss it as well.
Chris