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Insulated faston connectors, male-female, where to buy?

rv8ch

Well Known Member
Patron
I'm looking for some of these types of faston connectors, and can't seem to find them from the normal places I shop, like rs, stein, b&c. Distrelec has about a million types and it would cost me a lot to get a sample of each.

These came with my engine probes but I don't have a source.

There is a male and a female version, they of course mate and are insulated.

Or, if you have a better way to connect EGT and CHT probes, I'm listening! :)

IMG_5127.jpg
 
I have found fast-on connectors to be unreliable for thermocouple connections. Instead I use barrel crimps like these:

https://media.digikey.com/Photos/Molex/0191640053.jpg

Thermocouples operate at very low voltages and currents. Any corrosion in a connector produces an oxide film which introduces a tiny offset voltage in the connection. This introduces a large temperature indication error, which looks like a probe failure.

I provide plenty of service loop in the thermocouple wires for the eventuality of a probe wearout/replacement.

I had to replace all of my fast-on connections firewall forward in my Rocket in order to get reliable operation. Using the barrel crimp connectors provide gas-tight connections which minimize corrosion. Use the AviKrimp or PIDG brands, not the hardware store type.

Apologies for the thread drift.
 
I have found fast-on connectors to be unreliable for thermocouple connections. Instead I use barrel crimps like these:

https://media.digikey.com/Photos/Molex/0191640053.jpg

Thermocouples operate at very low voltages and currents. Any corrosion in a connector produces an oxide film which introduces a tiny offset voltage in the connection. This introduces a large temperature indication error, which looks like a probe failure.

I provide plenty of service loop in the thermocouple wires for the eventuality of a probe wearout/replacement.

I had to replace all of my fast-on connections firewall forward in my Rocket in order to get reliable operation. Using the barrel crimp connectors provide gas-tight connections which minimize corrosion. Use the AviKrimp or PIDG brands, not the hardware store type.

Apologies for the thread drift.

Thanks for the suggestions - I'm seeing exactly what you are describing. I will probably end up replacing all my connectors over time, so any hints in that direction are welcome.
 
Cheap is costly

All I can say is they are available at many many venues.
Just do not buy cheap or you will find one disconnected at the worst possible time.
Like the one on one of my dual fuel pump connections.
No Fast-ons there anymore. I like to have fuel to my engine. It actually runs better.
It was an E-bay supposedly good connector that vibrated loose.
You luck may be better.
Art
 
Those look like the ones I have from Electronics International. Perhaps they can source for you a small number.
 
CHT /EGT Connectors

Search for this post I did back in Dec 2018 > Erratic CHT and/or EGT ?
I now have almost 800 hours and the Omegas resolved my problems for almost 3 years now. Highly recommend them. Details are in that thread.
 
Search for this post I did back in Dec 2018 > Erratic CHT and/or EGT ?
I now have almost 800 hours and the Omegas resolved my problems for almost 3 years now. Highly recommend them. Details are in that thread.

+1 on the Omega mini-size thermocouple connectors. I got tired of futzing with the fast-on style connectors on all my EGT and CHT probes (no matter how good of a crimp I put on them, one of them would fail every 100-200 hours), so changed them all out and no problems since (knock on wood).

Be sure to get the correct ones for EGT and CHT probes, respectively (type J and K, not sure offhand which is which, IIRC).
 
EI recommends these OLC-2 connectors for thermocouple connections:
https://www.aircraftspruce.com/catalog/inpages/eioverlapolc-1-10-05470.php
Has anyone tried them? My #4 EGT is erratic so think about replacing the fast-ons with them.

Yep. They work great. I have them on an Aviat Husky (CGR 30P EIS) and an RV-8 (G3X EIS). I keep a spare set in the tool box to change out any Faston issues that arise. They seem a little funky to install until you get used to them. I have never had one problem with them.
 
Yep. They work great. I have them on an Aviat Husky (CGR 30P EIS) and an RV-8 (G3X EIS). I keep a spare set in the tool box to change out any Faston issues that arise. They seem a little funky to install until you get used to them. I have never had one problem with them.

Also, if you buy them direct with Electronics International they include the allen wrench. They sell them for $1 each in 5, 20 and 30 packs. As far as the Aircraft Spruce Q&A, don't believe half the answers they give. ACS provides wrong answers more often than good answers. The folks working there are not experienced aircraft mechanics or home builders and the company should shut down the horribly misleading Q&A.

https://www.iflyei.com/product/olc-2/
 
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