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prkaye

Well Known Member
I have a Dynon D-180. Recently it has started showing LOP almost all the time. Even with the mixture set full rich it sometimes shows PK or LOP. The engine seems to be running fine, it appears to lean normally (i.e. i lean it out, watch fuel flow gradually decrease, and eventually the engine starts to run rough when leaned too much). Idle-cutoff works. EGT readings on the Dynon all look reasonble (mostly in the 1300's, depending on power setting).
Any thoughts as to what could be causing the chronic LOP reading?
 
I would say that your fuel flow is off for some reason. If your FF is reading low the D180 will think you are LOP. Does your FF look right?
 
According to Dynon manual, for the EMS to calculate mixture in realtime 'EMS needs access to OAT, MAP, RPM, Altitude (from EFIS or GPS) and fuel flow, and be used on a normally aspirated engine that is close in performance to a ?stock? Lycoming/Continental engine'. Do any of these measurements appear out of specification? Also, have you made and configuration changes recently to the D-180 no mater how unrelated it may appear to be such as engine redline value?
 
prkaye said:
I have a Dynon D-180. Recently it has started showing LOP almost all the time. Even with the mixture set full rich it sometimes shows PK or LOP. The engine seems to be running fine, it appears to lean normally (i.e. i lean it out, watch fuel flow gradually decrease, and eventually the engine starts to run rough when leaned too much). Idle-cutoff works. EGT readings on the Dynon all look reasonble (mostly in the 1300's, depending on power setting).
Any thoughts as to what could be causing the chronic LOP reading?
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Hi,

My Dynon 120 shows peak and then LOP at about 1330 EGT real peake is around 1420 for my engine, so I really started to just not care about dunno leaning function, also my Dynon 100 attitude indicator does not work very accurate during turbulence, I will said it is affected by fish tail.
 
'EMS needs access to OAT, MAP, RPM, Altitude and fuel flow, and be used on a normally aspirated engine that is close in performance to a ?stock? Lycoming/Continental engine'. Do any of these measurements appear out of specification?
Click to expand...

I'll have do double check my MAP readings, but OAT, RPM, and altitude are all normal. I noticed yesterday that my fuel flow readings were fluctuating considerably at constant power settings - moreso I think than they used to. But it was not doing that constantly, and it didn't seem to be tied in any way to the mixture readings. I have a Red Cube fuel flow transducer. Are these things projhe to acting up?

Also, have you made and configuration changes recently to the D-180 no mater how unrelated it may appear to be such as engine redline value?
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Nope - no changes to D-180.

I'm not overly concerned if it's simply an instrumentation/measurement error, I just want to be absolutely certain it's not a symptom of a more serious problem lurking in the engine or fuel delivery system. As I said, the engine seems to be behaving normally, including leaning. Any thoughts on tests/checks I could/should do to rule out any serious problems?
 
Could it be due to MOGAS use...

Hi Phil,
I do have the same set-up as you (D180 and Red-cude) and my FF has been very stable.

Just a thought here:
You've been flying with MOGAS last summer. Did you drain it all before your "winter storage".
Auto gas is prone for "varnish" build-up when you let it sit for months.

You might have varnish build-up in the Red-cude transducer?

Mike
RV7A, Gatineau.
 
I do have the same set-up as you (D180 and Red-cude) and my FF has been very stable.
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Do you have a carb or FI?

hmmm... I think I started noticing this late in the fall or early winter before any varnish could have set-in. I've been topping it up with 100LL over the winter as well. If it is a varnish deposit in the FF transducer, what is the best way to fix this? Remove and clean it somehow?
 
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Any other thoughts on this? If my problem was caused by a varnish or some kind of deposit build-up in my FF sensor from the plane sitting with Autogas for a couple of months, how do I fix this? Do I need to get a new sensor, or can the build-up or deposits be removed by putting some kind of additive into the fuel?
 
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