Opening a Falcon g-meter

RV8Squaz · #1 01-19-2014, 05:00 PM

Hello Gang
I have a Falcon 2 1/4 g-meter that reads 1/2 g high throughout the range. Straight and level it reads 1 1/2 g and 2 1/2 g in 60 Deg bank coordinated turn. Has anyone taken one of these apart and successfully effected a repair? I could take it out and send it in for repair, but I'm curious and might learn something. I searched the internet, but nothing comes up. Thanks!

Jerry Esquenazi
RV-8 N84JE

flightlogic · #2 01-19-2014, 08:27 PM

Not complicated inside. Just remember where each part came from. Taking pictures during tear down is a help, if you get delayed putting it back together.

RV8Squaz · #3 01-20-2014, 06:11 AM

Thank you very much Flightlogic,
That is just the inspiration I needed. I thought they might be pretty simple. I didn't know if I would have springs popping out at my face as soon as I opened it. I will open it up sometime this week.

Jerry

JoeBlank · #4 01-20-2014, 10:13 AM

Jerry,

Mine failed after 100 hours or so. (No, I wasn't pulling THAT many G's!)

I decided to explore the unit partially because I wanted to see what made it tick and there might be a chance of an easy fix. After all, I do have the Repairman Cert for the aircraft...

With nothing to lose, I opened it up and found that the Dacron string that connects the counterbalances had shredded and broke. Took some pics as I started removing parts and was able to replace the string and button it back up with too much drama. A good learning experience as well. Works just fine now, and I learned something about G Meters...

Give it a try. The worst outcome is that you will have to send it in for repair...

RV8Squaz · #5 01-20-2014, 10:49 AM

Thanks a bunch Joe! I'll give it a try. After all, I too have a Repairman Cert!

Quote:

Originally Posted by Joe Blank

Jerry,

Mine failed after 100 hours or so. (No, I wasn't pulling THAT many G's!)

I decided to explore the unit partially because I wanted to see what made it tick and there might be a chance of an easy fix. After all, I do have the Repairman Cert for the aircraft...

With nothing to lose, I opened it up and found that the Dacron string that connects the counterbalances had shredded and broke. Took some pics as I started removing parts and was able to replace the string and button it back up with too much drama. A good learning experience as well. Works just fine now, and I learned something about G Meters...

Give it a try. The worst outcome is that you will have to send it in for repair...

RV8Squaz · #6 01-27-2014, 07:47 PM

OK Guys... Thanks for the inspiration. Today, my buddy and I took apart the g-meter and it is relatively simple, but there was bit more to it than I originally thought. Part of the complication is that mine is an internally lit model and so there is an additional bezel with a light magnifying glass between the outer glass and the instrument face itself. It's pretty cool. Consequently I had eight little screws to remove from the back of the bezel. Four small ones went into the lighting bezel only and the other four went through the lighting bezel and into the outer bezel. Once I had all eight screws removed, I still couldn't separate the bezels from the case because there was one remaining brass screw covered by some white potting compound camouflaged by a red "L" that I did not see initially. Once the bezels were removed, it was a simple matter to remove the three larger screws at the back of the case. These screws go directly into the frame of the instrument and once removed, the inner workings of the instrument will slide out as one unit. Important safety tip... The unit will not slide out if the knob on the back of the case is in the locked position!

Once the inner workings were exposed it was an easy matter to see what the different parts did. I quickly found were to make the adjustment. There is a "coil" spring similar to what you would find in a thermostat and the end is held by a small screw clamp. It was clear that the end of the spring had moved at some time. There was a factory marking on the spring and it appeared to have slipped. We grabbed the end of the spring with a hemostat and loosened the screw clamp, adjusted the spring, and tightened the screw clamp. That was it!

Installed the g-meter back in the panel. Total time for the job was about 90 min.

Joe, I saw the dacron string. I'm impressed you were able to get the string threaded properly! You should be a surgeon!

In addition to the g-meter. We looked for, found, and corrected, a minor static leak. The nylon elbow fitting going into the VSI was a bit loose. The pipe thread side was just starting to snug up when in the right position. I gave the elbow another complete turn, hooked the line back and re-tested. I now have a very tight system!

A good maintenance day today. Many thanks to my buddy for his help!

Jerry Esquenazi
RV-8 N84JE

JoeBlank · #7 01-28-2014, 11:18 AM

Quote:

Originally Posted by RV8Squaz

Joe, I saw the dacron string. I'm impressed you were able to get the string threaded properly! You should be a surgeon!

Great PIREP!

Jerry, they don't let me near anything sharp around here for good reason...

I also installed the unlit version of the G-Meter as I saw no need for night acro...

RV8Squaz · #8 01-28-2014, 01:07 PM

Quote:

Originally Posted by Joe Blank

Great PIREP!

Jerry, they don't let me near anything sharp around here for good reason...

I also installed the unlit version of the G-Meter as I saw no need for night acro...

No I don't do night aerobatics, but now I 'm tempted.

I do a lot of aerobatics. The Aeroshell guys make it look so easy! The reason I have a lit g-meter is simply due to symmetry. I'm kind of nuts that way. I have a very symmetrical looking panel. All of my instruments are internally lit. An unlit g-meter would have made it look like I had a black hole in that corner of the panel! I also do quite a bit of night flying.

JordanGrant · #9 04-25-2015, 12:37 PM

My Falcon g-meter was installed in 2005 and has never worked. I really didn't care much because I had a G-meter on my Dynon D10A display, anyway. But now I've decided to try to fix it. After discovering this thread, I opened up the G-meter. It looks like this when in pieces:

Caution: There is a small brass screw in the back that I think is an tamper-indicator, or seal of some type. It was covered in wax or something. I didn't know it was there and broke it when taking it apart. I don't think I care, since I'm not doing a certified repair.

As mentioned before, the G-meter works with a spring, a weight, and some strings that tie everything together. The internals of my G-meter look like the following.

Note that the strings are all messed up - they are just a tangled mess. The good news is that the string is not broken. The bad news is that I don't know how to route the strings back on the pulleys correctly. So does anyone know how the strings are supposed to go inside there? Does anyone have a picture?

RV8Squaz · #10 04-28-2015, 05:46 PM

Quote:

Originally Posted by JordanGrant

My Falcon g-meter was installed in 2005 and has never worked. I really didn't care much because I had a G-meter on my Dynon D10A display, anyway. But now I've decided to try to fix it. After discovering this thread, I opened up the G-meter. It looks like this when in pieces:

Caution: There is a small brass screw in the back that I think is an tamper-indicator, or seal of some type. It was covered in wax or something. I didn't know it was there and broke it when taking it apart. I don't think I care, since I'm not doing a certified repair.

As mentioned before, the G-meter works with a spring, a weight, and some strings that tie everything together. The internals of my G-meter look like the following.

Note that the strings are all messed up - they are just a tangled mess. The good news is that the string is not broken. The bad news is that I don't know how to route the strings back on the pulleys correctly. So does anyone know how the strings are supposed to go inside there? Does anyone have a picture?

Hello Jordan,

Gee, I wish I would have taken some pictures. I don't remember the exact routing of the string. I do remember it being wrapped around the pulley several times so that when the weight moved, the pulley turned with it. I don't remember what the other end of the string was attached to. I wish I could be of more help.

If it's any consolation, my g-meter has worked perfectly since I adjusted it.

Jerry Esquenazi
RV-8 N84JE