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N1463 Latest Report

JDA_BTR

Well Known Member
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.
 
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
 
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.
 
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.
 
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.
 
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.
 
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.
 
Did you get an answer?

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. Don?t know how many hours you have on your engine, but assume you are into double digits. I didn?t start experimenting with mixture until mid-teens when I became comfortable enough to start doing it.
 
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.

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.

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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It took about 6 weeks for my Repairmans Certificate card to arrive. The FSDO here in Baton Rouge was exceptionally helpful and it was very easy to get taken care of.

Opening that envelope was a really fun part of this build..... It's really done!
 
Flight testing failure of PFD/MFD

In the failure modes of flight testing now. G3X, dual GDU460, G5, GMC307. Pulled the keep alive breaker, then the PFD while in autopilot level on NAV. The autopilot dropped control, but after a few seconds I was able to push AP and restore NAV autopilot off the MFD. Pulled the MFD breaker and autopilot dropped off again. G5 indications showed AP error, then normalized. Was able to push AP again on the GMC307 and continue autopilot flight. Changed the course on my GTN650 and the autopilot steered the new course. Played around for long enough to decide that having full databases on the GTN helped with frequency selection on COM1 and that the VOR nav worked in this mode as well. Heading AP control worked fine. Then restored the MFD and PFD; both booted up and the autopilot dropped again. Reset the AP button and it worked fine.

Very robust setup. Not sure how I'm limited if the GMC307 fails.
 
In the failure modes of flight testing now. G3X, dual GDU460, G5, GMC307. Pulled the keep alive breaker, then the PFD while in autopilot level on NAV. The autopilot dropped control, but after a few seconds I was able to push AP and restore NAV autopilot off the MFD. Pulled the MFD breaker and autopilot dropped off again. G5 indications showed AP error, then normalized. Was able to push AP again on the GMC307 and continue autopilot flight. Changed the course on my GTN650 and the autopilot steered the new course. Played around for long enough to decide that having full databases on the GTN helped with frequency selection on COM1 and that the VOR nav worked in this mode as well. Heading AP control worked fine. Then restored the MFD and PFD; both booted up and the autopilot dropped again. Reset the AP button and it worked fine.

Very robust setup. Not sure how I'm limited if the GMC307 fails.

I'm pretty sure you can do all the GMC307 functions from the PFD, just not as convenient. Section 9 of pilots guide (at least in the version I have handy)
 
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Ok good. I?ll fail the 307 and check it out. I bet the YD functions to anticipate turns aren?t there without it but will see.
 
One minor limitation I found during failure testing with an almost identical setup is that with the PFD failed, the MFD does not show the magenta line for the GPS course, though it follows it. Garmin says it?s because there?s an RS232 backup (AP to GAD29?) not supported on the MFD. It?s of course viewable on the 650.
 
IFR transponder/altimeter checks complete no squawks.... 41.1 hours put the appropriate logbook entry in and BAM -> phase 2...... Sweet

Anybody want to do the acrobatic certs? I didn't....
 
Nosewheel Breakout Force

I was having to progressively tighten the nose wheel fork nut because the breakout force kept getting lost. The inflight symptom was a lot of left ball as the prop would push the nose fairing over causing unwanted yaw trim.

So I removed the nut and checked the two belleville washers; installed correctly but well greased. I guess when I greased the nose fork zirc I put in too much, so it ran down in the heat into the belleville washers. Cleaned, dried, reinstalled and on test flights since then have had no nosewheel-induced yaw..... Will see if it stays adjusted.
 
I was having to progressively tighten the nose wheel fork nut because the breakout force kept getting lost. The inflight symptom was a lot of left ball as the prop would push the nose fairing over causing unwanted yaw trim.

So I removed the nut and checked the two belleville washers; installed correctly but well greased. I guess when I greased the nose fork zirc I put in too much, so it ran down in the heat into the belleville washers. Cleaned, dried, reinstalled and on test flights since then have had no nosewheel-induced yaw..... Will see if it stays adjusted.

Vic Syracuse recommends greasing the washers. Interesting finding. I've had to tighten mine once (exact same symptoms), but good so far since then. Moderately lubed the washers when I installed them then filled the zerk until it mooshed out above & below.
 
Seems a decent idea to lubricate a bit; mine were heavily greased. I'm probably going to mess with this some more before I'm done.....
 
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