G3X

[stamper]

Just started flying my rv10 with the G3X, can someone tell me that is also flying with this if their fuel PSI fluctuates just a little or is it rock solid. I get fluctuation like 23.4 to 23.7 or so constantly my MP will fluctuate about .1 or .2 up and down pretty constantly but not as frequent as the fuel pressure.

I just can't remember if it has always been that way or not and I only have 10 hours on the plane right now so if someone that flies theirs if they could take a look and let me know if it should stay solid or a few 10ths of movement is not that big of deal. Thanks in advance

[Bill.Peyton]

Do a search on snubber device for manifold pressure. Without one you will see these type of fluctuations. I suspect the same is true for the fuel pressure. I have snubber so on both sensors, which cured the issue for the Garmin G3x

http://www.vansairforce.com/communit...hlight=Snubber

[Jesse]

When we talked, I though you were seeing fluctuations of 23 to 27psi, not 23.4-23.7. That type of fluctuation would worry me. Many devices have an algorithm that smoothed out changes and gives an average reading over a longer period of time (not long, but longer than the instantaneous value). We used to see those types of fluctuation from our Dynon D-10 EMS over 10 years ago. They smoothed things out. I don't remember seeing it in fuel pressure, but I wouldn't be surprised. Just like manifold pressure picked up from a cylinder, where the intake stroke is what causes the reading of manifold pressure, the pump only creates pressure as the plunger is pushing on the pump lever. It sounds like a snubber device might help.

[clutch22]

Another option other than The various McMaster restrictors...

From the G3X install manual:
"A restrictor or snubber fitting (not available from Garmin) may be installed to dampen manifold pressure fluctuations. One example is the PS-8G fitting from Omega Engineering."

I'm at the point of hooking all this stuff up on my build. I initially wasn't going to worry about it, but looking at some of the older posts on this issue, it seems to be an annoyance to pilots. Maybe I'll reconsider, and get it headed this way.

[stamper]

Ya after I talked to you I went and looked over the wirring after I cleaned my fuel filter and I did find a bad wire on the MP. This fixed the big fluctuation I had but I still have just a small movement of a .1 to .3 back and forth on both MP and the Fuel pressure read out. was just seeing if that was normal or if it should of be rock solid.
With not much time behind the plane I wasn't sure. Thanks for talking to me the other day.