RV12 Rotax 912 Occasional Erratic EGT indications

[dabney]

The engine has 100 hours on it. On the FlightDEK D 180 the EGT L and R consistently run about 1250-1260 usually within about 10 of each other. Without any change in the throttle EGT L will rise to 2000 for a for 5-10 seconds which of course sets off the alarm for high EGT. Then they return to the previous "normal" indication.

Can't think of an explanation for this myself, any ideas for troubleshooting or prior experience with similar problem?

[Piper J3]

Possible wiring connector needs cleaning or EGT thermocouple is bad. I had both issues. Replaced thermocouple at ~ 100TT.

EGT, Hose Clamp, 0.75-1.25", Rotax SKU: #100405-001 $46.89. Bought directly from Dynon in 2016

[RFSchaller]

I?m on my third EGT probe at 816 hr TTAF. The first one failed at about 260 hours. Second was a faulty replacement part that was bad from the day I put it in. The third has over 650 hours on it. The right EGT has never been replaced.

Before you buy a replacement swap leads in the engine compartment and verify the issue swaps with the probe.

[JBPILOT]

I recently replaced my first one at over 1,100 hours. I did have connection issues a couple time thru the years.

[Charlie12]

I started having occasional erratic temp indications on my left EGT at about 70 hours. Re-crimping the wire connectors up near the firewall penetration fixed it. At my next condition inspection I replaced the thermocouple because I didn't trust it, but it may be that I was being too cautious.

[AirHound]

Other than hardware (sensor and connections) and software what can cause actual 912ULS EGTs to differ?

[RFSchaller]

If one carburetor is running leaner than the other it would cause that side to run hotter since the balance tube doesn?t do much at cruise RPM. But that wouldn?t cause spiking.

[Azjulian]

I had this happen early on (20 ish hours) I re-crimped both prove leads and it?s been solid since

[AirHound]

Originally Posted by RFSchaller

If one carburetor is running leaner than the other it would cause that side to run hotter since the balance tube doesn?t do much at cruise RPM. But that wouldn?t cause spiking.

Rich, in general, is the only way to adjust mixture on our machines just at idle with the set screw ie; 2 vs 1.5 turns?

Otherwise, it?s mostly about the internal environment/material condition of the Bings regarding mixture at cruise speeds?

I was under the impression that the balance tube was mainly effective at higher RPM?

Regards,
Doug