Engine Monitor Poll

[0TreeLemur]

Since Engine Monitor Discussion is a relatively new category, let's generate some data to discuss.

[47U]

Which temperature would be more useful in the data download; OAT, or carb air temp?

I’ve got an EI UBG-16.  To gain a more complete picture in my downloaded data, I’m adding modules for RPM, fuel flow, and MP.  I was going to move my carb air temp from the FP-5 to the UBG, or would OAT be more advantageous and leave the carb air temp where it is?  

 

[McMooney]

No, but will eventually get a garmin 275

[Rjfanjet]

Just got the JPI 730. Have the 8 hole panel to replace the original, then installing the JPI. Put 215 hours on the plane in the last 3 years since I've owned her. No issues so far, but I've replaced a lot of parts.

[kortopates]

On 8/10/2022 at 7:49 AM, 47U said:

Which temperature would be more useful in the data download; OAT, or carb air temp?

I’ve got an EI UBG-16.  To gain a more complete picture in my downloaded data, I’m adding modules for RPM, fuel flow, and MP.  I was going to move my carb air temp from the FP-5 to the UBG, or would OAT be more advantageous and leave the carb air temp where it is?  

 

So I assume your dumping the FP-5 fuel computer to add FF to the UBG-16 along with RPM & MAP. You can't have too many probes so I'd want to add the carb air temp and OAT to the UBG-16 at the same time your doing UBG-16 install. I'd also be looking at oil temp and pressure if not yet there. You'll have a choice between a CHT piggyback or adapter probe versus a spark plug probe; be sure to go with the piggyback style since its the more accurate non-standard probe.

[201er]

An engine analyzer is the third most useful panel add-on after an angle of attack indicator and GPS.

[47U]

1 hour ago, kortopates said:

So I assume your dumping the FP-5 fuel computer to add FF to the UBG-16 along with RPM & MAP. You can't have too many probes so I'd want to add the carb air temp and OAT to the UBG-16 at the same time your doing UBG-16 install. 

I had the carb air temp input to the FP-5 when I installed it almost 10 years ago.  I put in the UBG a couple years ago when TSO’d probes for the Westach analog were no longer available, but i didn’t add any other function modules to the UBG at that time.  And you’re correct, I used the piggyback ring CHT probe under the factory bayonet fitting on #3 cylinder.  If the ring probe is wrapped in some fire sleeve, the temperature reads right inline with the other three cylinders.

After overhaul and break-in of my #3 cylinder last year I discovered that I want more data in my downloads.  E.I. says that I can add a fuel flow module for data input to the UBG and keep the FP-5, too.  I hadn’t considered oil temp and pressure modules as a priority, but you’re right, you can’t have too many probes.  Besides, they’re a good cross-check with the factory analog gauges.

Thank you for your input.

[Vance Harral]

3 hours ago, 47U said:

but you’re right, you can’t have too many probes

I don't necessarily disagree with this statement.  Just be aware that the more probes you have to monitor more stuff, the more opportunity you'll have for probes/wiring to go bad and need to be replaced.

I've had good experiences with low temp stuff like oil temp/pressure, have never replaced one of those.  But it seems like I have to chase a bad CHT or EGT probe about once a year (sometimes the probe itself, sometimes the wiring).  Some pilots I've spoken with claim to have never had to replace a temp probe, others have experiences more like me.  I sometimes wonder if the problem is mainly vibration, noting that some airframe/engine combinations simply run smoother than others.  A non-counterweighted Lycoming IO-360 is a great engine, but isn't what most people would characterize as smooth, even with dynamic prop balancing.

[47U]

2 hours ago, Vance Harral said:

Just be aware that the more probes you have to monitor more stuff, the more opportunity you'll have for probes/wiring to go bad and need to be replaced.

The EGT probes in my (now removed) Westach analog gauge were not robust.  So far, the E.I. EGT probes have been solid.  Does it matter how far down the riser, away from the cylinder head, the probes are placed?  Further away = less heat?  

[Vance Harral]

16 hours ago, 47U said:

Does it matter how far down the riser, away from the cylinder head, the probes are placed?

That's a good question, but ours are not particularly close to the cylinder head.  We have an E.I. engine monitor also, and the installation manual suggests that the "ideal" location for EGT probes is 1.5" from the exhaust ports.  Ours are more like 4" down, because the exhaust already had existing EGT probe holes there for a prior system, and I felt the position wasn't critical enough to warrant welding up the old holes and drilling new ones.

Also, we choose to use the P-110-F "fast response" probes, which are arguably more fragile than the P-110-R "robust" probes.  That might have something to do with longevity.  That said, we've had as many CHT probes fail as EGT probes over the past decade.  We also had a lot of trouble with the thermocouple wire cracking at the quick-connectors, back when EI was still using spade-type connects.  We used to find a break every few months or so.  That problem seems to have mostly resolved with the introduction of the OLC connectors.  I was kinda irritated at EI over connectors, because their support reps assured me on multiple occasions that there was not a widespread problem with the spade connectors, and that there must have been something about my installation that was causing them to break.  Then they "suddenly" announced the OLC style connectors, but it must have just been coincidence, right?