EGT readings

[lfussell]

Last year I replaced all of my EGT probes after an engine swap. Last week I got a red X on the #3 EGT. In a runup, yesterday #3 was substantially below the other temps. per the attached photo. any suggestions would be appreciated.
Regards,
Larry

 

[rvator51]

Previous posters have reported success with re-crimping or replacing the crimp connectors on the EGT probes or the probe may have went bad.

 

[DBRV10]

Buy yourself about 30 OLC-1 joiners from Aircraft Spruce and use them ;-)

 

[Raymo]

If replacing the connectors doesn't solve the issue, you should look at a fuel/air mixture issue. The CHT on that cylinder is also a bit lower than the others...

 

[mmarien]

My friend had an engine monitor installed in his C185. When the temps acted up he would find that the set screw for the OLC-1 connectors had come loose. Go figure. When I bought some better quality EGT probes a few years ago they came with the OLC-1 connectors. I didn't use them. I crimped on hardware store blade connectors and haven't had any problems. I do have a ratchet type crimper. I think a good quality crimper is the secret to good connections. Your experience may vary.

 

[jakej]

Like Marien I use the AMP brand blade (spade) connectors with no issues now that I also use a spray product eg Inox on them & a good quality crimper.

 

[DBRV10]

My friend had an engine monitor installed in his C185. When the temps acted up he would find that the set screw for the OLC-1 connectors had come loose. Go figure. When I bought some better quality EGT probes a few years ago they came with the OLC-1 connectors. I didn't use them. I crimped on hardware store blade connectors and haven't had any problems. I do have a ratchet type crimper. I think a good quality crimper is the secret to good connections. Your experience may vary.

Yep, just like blades, they can all become loose. They all need doing up tight, be they crimped or OLC-1.

In the OLC-1 you only have one connection to be tight, not two. And you can nip them up with an allen key. Blades can be the blade or the crimp.

As you have noted a good crimp really helps and a good crimper, as Jake uses and obviously you and I do helps.

Vibration is a thing.....balancing the prop affects many things. These too.

YMMV but the OLC-1 is not inferior despite your experience, and it may be superior on averages, provided it is done up correct.

There is no perfect answer, but if it is blade or OLC, do it right!

BTW many of us in this part of the world have had way more problems with crimps and they all bug me for a handful of OLC's.

You can read into that anything.

 

[mmarien]

YMMV but the OLC-1 is not inferior despite your experience, and it may be superior on averages, provided it is done up correct.

David - I didn't say the OLC-1 connectors were inferior. I said they came loose. My spade (I stand corrected on the name) connectors haven't come loose in the last 500 hours but now that you bring it up, I'll keep an eye on them.

 

[jakej]

If you’re using the AMP brand I’ll guarantee they won’t go loose, actually they are very hard to take apart without breaking the wire - so I usually use tools to do the job of taking them apart if/when needed.