wire of the EMS brown harness are too long

[flaude]

I am starting to install the EMS harness (the brown one for EGT and CHT). I would like to know if it is possible to cut those wire because they are very long. Of course I will not cut the silver one that are directly plug in the engine!

thanks

 

[mmarien]

I cut the brown wires on the EMS 25 pin wiring harness to length for my SV installation. Each pair is the same length but I cut the pairs different lengths to fit.

 

[flaude]

So no problem to cut the brown wire. Some guy told me that it was calibrating and that you could not cut it. So that was wrong

thank you!

 

[mmarien]

Honest - straight from Dynon:

http://dynonavionics.com/cgi-bin/yabb2/YaBB.pl?num=1268674167/1#1

 

[dynonsupport]

You can cut them down, no problem. What does matter is that the CHT/EGT wires don't have any temperature change across a non-thermocouple junction (ie, if you cut them at the firewall, and had some connector on the firewall that isn't made specifically for thermocouples). Also, if you EXTEND those wires, that you use type J thermocouple wire for the CHTs and type K thermocouple wire for the EGTs. We sell both types.

 

[flaude]

Thank you for the fast and effective informations.

 

[swatson999]

So, given the veeeerrrry long wires on the probes themselves (EGT and CHT), what are people doing with them? Looping them around, flaing them back and forth, etc.?

Other installations that I've seen have the EGT and CHT probes with very short wire leads, maybe a few inches, and then the harness goes out to that point. Dynon has very long probe wires, it seems, and I'm just trying to figure out what to do with them (and avoiding cutting them/recrimping on connectors, etc.).

 

[mmarien]

I just assumed that the long probe wires were made for harsh environments (wire braid cover) so I used the length to make the connections to the harness at the back of the engine well away from the heat of the exhaust and cylinders themselves.

 

[alpinestar]

Im planning to put two small 8-position terminal strips on the firewall, trim both the ems harness and the probe leads as needed, and use normal ring terminals to attach the to the terminal strip.... Good/bad idea? I understand that the junctions need to be a uniform temperature (should be!); curious if there is a specific thermocouple crimp terminal or just use the "red' ones like everywhere else. Thanks!

 

[mmarien]

I used regular crimp type connectors. Can't remember if they came with the kit. They seemed to work fine. The terminal connector sounds like a good idea for neatness but reply #4 above may rule out the use of a terminal strip. Although you would think it would be the same as using crimp connectors.

On the same note, I replaced all my EGT probes and the new ones (non Dynon) came with really short wires. Luckily I left an extra loop of the thermocouple wire for stress relief just off the EMS module so I was able to pull more wire through the firewall and still connect to the short probe leads. Just a heads up if you ever have to replace the probes. They are often referred to as consumables.