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Engine Readings - Good and Not So


EricB

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So there have been some limited discussions of problems or issues people have seen but I'd like to see what people are NORMALLY seeing.  What readings do you see in normal flight, during taxi and/or runup, etc.  Indicate what you think is normal and any issues you may have had so we can all learn.

I've attached a screenshot from today's flight showing what I think are very normal cruise indications.  I will say my Generator light flickers a lot at anything below 2000 rpm and elsewhere on the forum I saw some suggestions about that.

When I got this plane, many of the readings fluctuated radically but we've worked it down to only the generator light being weird. 

Engine Instrument.JPG

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This is mine from earlier this month. Don’t remember the altitude or outside temperature though. I’ve never had any issues with flickering or warning lights. EGTs have always been a little farther off than I like.IMG_3571.thumb.jpeg.def0bc454e2608429dbb18f69dc8a9ed.jpeg

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Last one, here's what it looks like when you take the iS into the 98-100% throttle, which goes out of eco mode. It goes open-loop on the ECU and dumps extra fuel in, which is like being "rich of peak", the EGT drops.

Note on the throttle/flow graph, black is flow, blue is throttle.

 

Screenshot 2023-11-16 at 7.43.30 PM.png

Screenshot 2023-11-16 at 7.43.38 PM.png

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Your volts seem pretty low for this rpm.

My regulator just went bad last week after over 600 hours of service . I was seeing intermittent low volts warmings here and there for the last few weeks and then it just died ( ironically during my annual at my mechanics shop - probably the best place for this to happen )

Here is a graph of my volts vs rpm on my flight to his place ( it is steady about 13.7 volts for the whole cruise but it was dipping during run-up and then during landing on idle)

 

 

Volts_11th.png
 

The second one is when my mechanic was running the engine on the ground - it briefly went to 13.5 or so volts and then went downhill and never recovered regardless of the rpm.

Volts_14th.png

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22 hours ago, EricB said:

So there have been some limited discussions of problems or issues people have seen but I'd like to see what people are NORMALLY seeing.  What readings do you see in normal flight, during taxi and/or runup, etc.  Indicate what you think is normal and any issues you may have had so we can all learn.

I've attached a screenshot from today's flight showing what I think are very normal cruise indications.  I will say my Generator light flickers a lot at anything below 2000 rpm and elsewhere on the forum I saw some suggestions about that.

When I got this plane, many of the readings fluctuated radically but we've worked it down to only the generator light being weird. 

I have seen more than once when the blinking generator light was a predecessor to a voltage regulator failure.  

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Happy Thanks Giving all. 
 

Tried other Flier posts without response . Forgive me for throwing in a topic here. 
Problem: I’ve been told by IC techs and others that the whine (intensity is directly related to power changes) in my phones is an RFI related/Ground loop thingy. 

Every grounding point has been cleaned and tightened, head phone jacks have isolators in place. No change. 

Haven’t looked to see if mfg shielding is touching anything near connecting points in the mike jack or the wiring condition of the optional limo jacks.

Anyone out there eliminated this demon please share.

Eternally Thankful,

Doug

 

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First - RFI and ground loop are very different things.  Ignore anyone who doesn't know the difference.  All alternators put out RF interference; its the nature of the beast.  But, that RF should not be transferred to the DC circuits that power our radios and audio gear.  You failed to mention just what the issue was.

If the RF is coming down the DC line, it might be that the capacitor that's supposed to "smooth out" the voltage post being coverted to DC is not doing its job.  In that case it is either the capacitor itself, or insufficient grounding of the minus side of the cap.  If the RF is being "picked up" by other wiring then shielding or grounding of those leads is the issue.  

There is a ground buss on the firewall of the CTLS where several items are grounded.  You should check that all those connections are tight, not corroded, and done with sufficiently large wire that the wire itself does not offer a resistance to ground.  Anything that seems to be "grounded" with a very light gauge wire should have that wire replaced.  Also note that ground wires should be "home run" to the ground buss and not daisy chained through another "possible" ground point.  

If the shielding is "touching something" that would not cause an issue as the shield wire had better be grounded or it isn't really a shield wire.  

I have no idea what a "limo jack" is.  That's not a standard engineering term.  

 

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Just for completeness, a "ground loop" happens when a circuit is grounded at more than one point but those 2 points do no agree on what is ground.  That is, a voltage exists between the assumed ground points.  In most audio circuits this results in a hum since we supply 60 Hz AC to our gear in the USA.  

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