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  #1  
Old 06-28-2019, 02:12 PM
JDA_BTR JDA_BTR is offline
 
Join Date: Dec 2013
Location: Baton Rouge, LA
Posts: 790
Default N1463 Latest Report

At 5500ft density altitude cruises with 197MPH (171kts) throttle full in at about 10.1 GPH leaned to peak EGT and 2300 RPM. Temps are high right now (93 deg today).

The initial flights' left yaw was solved by tightening up the nose wheel breakaway force; was far too loose even though carefully set in the past. Will add to the condition checklist. Yaw is good now no trim tab needed I think.

CHT 1/2 higher than 3/4. 3/4 hang together, #1 10-15 higher, and #2 is 25-30deg higher than #1. Consistent through the flight. EGT about same on all within 30-40 degrees of each other.

Perhaps too much air passes by 1/2 and flows to 3/4? It if was a fuel problem I think that the EGT would be consistently lower on 2 and it is not. 7.1 hours on the engine maybe it is too early to care about it. First oil change at 5 hours was uneventful nothing in the oil or screen.

Changed my autopilot setup to not have roll/pitch trim enabled with servo function. Still think the screens for autopilot and trim setup don't match what is in the latest installation guide. Will continue to assess. Autopilot works great.
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  #2  
Old 06-29-2019, 06:46 AM
cajunwings cajunwings is offline
 
Join Date: Jun 2007
Location: new iberia la
Posts: 623
Default Early in the game.

All sounds really good for this stage of the break in. I would go to 40-50 hrs before thinking about tweaking the baffles or injector nozzle tuning. Thanks for the report.

Don Broussard
RV9 Rebuild in Progress
57 Pacer
A&P/IA ect
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  #3  
Old 06-29-2019, 06:45 PM
JDA_BTR JDA_BTR is offline
 
Join Date: Dec 2013
Location: Baton Rouge, LA
Posts: 790
Default

Good advice. Iím wanting to dynamic balance too.
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  #4  
Old 06-30-2019, 09:21 PM
RicoB RicoB is offline
 
Join Date: Mar 2017
Location: Glendale, CA
Posts: 189
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On my engine break in I saw hotter temps on #2, than #1, #3 and #4 close to the same numbers.
Now 90hrs later they are all pretty even with the #2 slight hotter than the rest.
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  #5  
Old 07-01-2019, 09:05 AM
rvator10 rvator10 is offline
 
Join Date: Apr 2006
Location: Fountain Hills, arizona
Posts: 98
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Question, at your power setting (throttle full in at about 10.1 GPH leaned to peak EGT and 2300 RPM) would that be around 80+% power? what are your exhaust temperatures? is this risky of burning a exhaust valve?. just asking because im breaking in my engine = running it hard, and Im ROP 100 degs in fear of excessive exhaust temps.
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  #6  
Old 07-04-2019, 09:41 PM
JDA_BTR JDA_BTR is offline
 
Join Date: Dec 2013
Location: Baton Rouge, LA
Posts: 790
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I run it a little ROP btwn 65 and 75 percent. Today I adjusted the wing aileron push tubes a half turn shorter to better rig the ailerons each about a 1/8 or so up. The 6 position elevator trim connector was loose so got that set right.
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  #7  
Old 07-05-2019, 08:58 PM
JDA_BTR JDA_BTR is offline
 
Join Date: Dec 2013
Location: Baton Rouge, LA
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And..... the elevator trim motor connector just didn't cut it. The one that snaps into the aft fuselage and takes the connector from the trim motor is just fine, potted and installed as directed. It is the connector further out that goes to the motor/sensor itself. It just hangs in space inside the elevator and doesn't stay together.

So I used the technique of each wire having a pin/socket from my avionics leftovers. The pin/socket is heat shrink covered, and the group of 5 such are covered together with heat shrink again. Won't be coming apart, works great, can live inside the elevator forever. Didn't want the full shell for both sides of a DB9.

I like the form factor of the micro-mini Molex connectors, but they are finicky.
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  #8  
Old 07-06-2019, 05:04 AM
mturnerb mturnerb is offline
 
Join Date: Apr 2015
Location: Ponte Vedra, FL
Posts: 1,011
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Quote:
Originally Posted by JDA_BTR View Post
And..... the elevator trim motor connector just didn't cut it. The one that snaps into the aft fuselage and takes the connector from the trim motor is just fine, potted and installed as directed. It is the connector further out that goes to the motor/sensor itself. It just hangs in space inside the elevator and doesn't stay together.

So I used the technique of each wire having a pin/socket from my avionics leftovers. The pin/socket is heat shrink covered, and the group of 5 such are covered together with heat shrink again. Won't be coming apart, works great, can live inside the elevator forever. Didn't want the full shell for both sides of a DB9.

I like the form factor of the micro-mini Molex connectors, but they are finicky.

I had already eliminated the one you describe but found the snap-in one to be just as problematic. It failed in flight at any speed over about 80 knots. I replaced it with a better connector (Deutsch DTM) - will be less convenient when I pull the elevator off to paint but zero issues since replacing. Van's seems to recognize the weakness of these connectors - I don't think they used any in the RV-12is and hopefully will eliminate them from the -14 over time. I have a few remaining (control sticks and connector in front of flap motor) but plan to replace them over time when I'm working in those areas.
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  #9  
Old 07-06-2019, 07:44 AM
Don E Don E is offline
 
Join Date: Aug 2016
Location: West Chester, PA
Posts: 78
Default Did you get an answer?

Quote:
Originally Posted by rvator10 View Post
Question, at your power setting (throttle full in at about 10.1 GPH leaned to peak EGT and 2300 RPM) would that be around 80+% power? what are your exhaust temperatures? is this risky of burning a exhaust valve?. just asking because im breaking in my engine = running it hard, and Im ROP 100 degs in fear of excessive exhaust temps.
There are plenty of threads here about operating the engine during and after break-in. But during break-in running WOT is a great time to experiment with ROP and LOP mixture settings, just keeping an eye on temps. I did and never saw EGTs above 1450 F. Just keep aneye on it. I also reviewed my data logs after each flight, using Savvyanalysis. Donít know how many hours you have on your engine, but assume you are into double digits. I didnít start experimenting with mixture until mid-teens when I became comfortable enough to start doing it.
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  #10  
Old 07-06-2019, 10:16 AM
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DanH DanH is offline
 
Join Date: Oct 2005
Location: 08A
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Quote:
Originally Posted by rvator10 View Post
Question, at your power setting (throttle full in at about 10.1 GPH leaned to peak EGT and 2300 RPM) would that be around 80+% power?
Depends on manifold pressure, i.e altitude.

Quote:
what are your exhaust temperatures? is this risky of burning a exhaust valve?. just asking because im breaking in my engine = running it hard, and Im ROP 100 degs in fear of excessive exhaust temps.
Exhaust valves in normally aspirated engines generally "burn" because of poor seat contact, not mixture setting. Any part of the valve circumference not in full contact with the valve seat can't transfer heat, so that portion of the valve is hotter than the rest. The valve begins to erode. Hot combustion gas leaks through the gap, and things cascade; more heat, less heat transfer, faster erosion, until it begins to melt, or fails mechanically due to loss of strength at the elevated temperature.

The quality of valve seating is a fabrication issue for your engine supplier. Some do a great job, and others don't. Sure, less heat stress is better than more, so the pilot has a role. However, if you have a leaky exhaust valve, running 100F less EGT is not going to make much difference in the long term outcome.

Quote:
Originally Posted by Don E View Post
But during break-in running WOT is a great time to experiment with ROP and LOP mixture settings, just keeping an eye on temps. I did and never saw EGTs above 1450 F.
The absolute value of EGT is meaningless. The 1450 F value (for example) is an average temperature. The valve is closed during most of the 720 degree cycle, sitting on its seat and cooling. When the valve is closed, there is no gas flow past the EGT probe, and it too is cooling. When gas is flowing, the gas temperature varies through the valve open period.

That said, the average exhaust valve temperature does mirror the average gas temperature. They are not necessarily the same temperature.

The other factor making absolute EGT values meaningless is probe position.
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Last edited by DanH : 07-06-2019 at 10:19 AM.
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