Replacement EGT Probe Recommendation

[jdubner]

Is there currently any consensus on replacement EGT probes for the EMS-220 module?  Reliability and long-life are my main criteria but low to moderate cost is also important to me.

Thanks,
Joe

 

[mmarien]

I think if you're looking for better quality then the cost will increase. I looked for something that was advertised to handle higher temperatures. The Dynon probes started to burn out after I installed electronic fuel injection and was running near peak EGT (1600F+). I think these are the ones I bought. They've lasted about three hundred hours so far but I run way LOP now so the EGTs are cooler (~1400F).

 

[preid]

Sadly I have replaced 3 or so of the original Probes. I bought the GRT long life-http://www.aircraftspruce.com/catalog/inpages/egthcsll.php?clickkey=470426 and they have worked well thus far.

 

[jdubner]

I think if you're looking for better quality then the cost will increase.

Yes, I would expect to pay more.  But yikes -- $440 for a set of four!

I bought the GRT long life-http://www.aircraftspruce.com/catalog/inpages/egthcsll.php?clickkey=470426 and they have worked well thus far.

Now that's what I wanted to hear!  How many hours on them at this point?  Are they compatible with the Dynon probes or does one need to change all cylinders' probes at once?

--
Joe

 

[kurtfly]

I have used the Electronics International probes in my Glasair w/ Lyc IO-360 and have had no failures in over 1100 hours. These probes are thicker than most others. The downside is they are slower to respond. so it takes a little longer to lean...

 

[Dynon]

I can say that over the past few years we've made several rolling changes to our EGTs to improve them. Time will tell whether that equals a more robust probe over time, but if yours are more than a couple years old, the new ones are different (and we hope will last longer).

 

[rlmarshall]

Can EGT and CHT probes be interchanged and installed in a "mix and match" way. Or do they need to be bought as a set of 4 (or 6, etc.)
Thanks

 

[jdubner]

I can say that over the past few years we've made several rolling changes to our EGTs to improve them. Time will tell whether that equals a more robust probe over time, but if yours are more than a couple years old, the new ones are different (and we hope will last longer).

My original probes are Dynon part number 100405-000 Rev H.  Can I expect an improvement over that and what is the replacement part number?

Thanks,
Joe

 

[Dynon]

They're all type K thermocouples, so fundamentally they're the same sensor. You may see, just in general, small variances in absolute temperatures when you mix and match, even when replacing with the same exact probes, because the metallurgy and junctions to age a bit over time. But with EGTs you're mostly concerned with the peak and not the "number", at least to first order.

The replacement part numbers are the same. You'd get a newer revision if you ordered a replacement, and as I said, time will tell whether or not the continuous improvements we've made will yield a more durable probe (we just have to wait and see how they fare in the fleet over time). But yes, we'd hope that you'll see an improvement.

 

[jc2da]

I just recently replaced a probe that went wonky. The new probe temps were quite a bit higher about 100 to 200 F or maybe more. I was a bit worried about the engine - was it an exhaust valve leak, etc.

I decided to try using a torch to light up 2 probes, 1 old 1 new, safety wired together. It was quite obvious what was going on. No problem on the engine at all. It has to do with the new probe vs old probe.

The old probe has some crud on the outside. It appears this crud acts like an insulator of sorts. The new probe, with its shiny new SS, got cherry red quickly and came to temp quickly. That is pretty much exactly what the EGT readings are saying.

Thus, for anyone installing new probes, i would say expect much faster temp response and higher values for EGT values. Not sure how long it will stay this way. I imagine the new will start acting like old ones in due time.