CiES fuel sender problem with bladders

[UteM20F]

Hello friends.  My son, two friends, and I bought a '67 M20F a year ago.  We love her!  We just had a new all-Garmin panel installed and paid extra to mate the G3x with CiES fuel senders for accurate fuel levels.  We have O&N bladders from 1995.  We've flown for 35 hours since the panel upgrade and the levels have been spot-on except for 3 instances recently that incorrectly showed full fuel in a tank for the remainder of that flight.  Once in the left tank and twice in the right tank.  We sent the diagnostics file to the avionics shop and they verified that the sender reported that during the flight, the fuel level changed from about 18 gallons to 32 gallons, and stayed there.  These are all brand new senders, and it has now happened on both tanks.  The shop called CiES and they reported this is a known issue with certain bladders, something about the magnetism of the material that the bladder is made of reacting badly with the senders, and they get 'stuck', thinking the fuel level is full.  I sent an inquiry to Griggs Aviation (they purchased O&N) and asked if they were aware of the problem.  They responded this is the first they've heard about it.

Have any of you seen or heard of this issue before?  At this point, neither we nor the shop knows how to proceed, other than to not rely on the fuel gauges.

Thanks!

Ute

p.s. This is my first post, but have watched every thread now for a year.  I tried to find info that's already there and failed, with this being the closest thread: 

 

[Marauder]

I’ve had CiES senders with my bladders since 2017 and have never experienced what you are seeing. Not sure what kind of metal would be in an O&N rubber bladder.

I did have an issue with the CiES sender orientation. If it is installed right side up, it is pretty close to the bladder wall. I could see a scenario where fuel sloshing around in turbulence might cause the float to change position - but that sounds like a reach.

Are you running them in frequency or resistance mode?


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[MoonFlyer68]

I also have bladders and the CiES senders with no issues.  Mine have been installed since 2018.

[UteM20F]

Thanks Marauder,

The CiES web site claims these senders are Magnetic Field based while the competition and legacy senders are Capacitive, Resistive, Ultrasonic, or Reed Switch based.  I admit I don't understand how it works.  I'll be calling CiES myself after I research a bit more.  I'll probably call Weep No More and ask if they've heard of this. It really stinks to have spent so much for accuracy and then not be able to trust what they tell me.

There was no turbulence at all on the flights when the senders got stuck.  

Ute

[UteM20F]

Thanks for your help.

I reached out to Paul at Weep No More.  Turns out he co-owns a MSC, Oasis Aero in Willmar, MN, and has seen this exact issue on many Mooneys.  He recommends that when I see the problem again, that I pull the circuit breaker for the CiES senders, wait for a few seconds, then reset it.  He expects that this will cause the senders to report the proper amount of fuel.  Paul and his partner are still trying to get answers from CiES.

Ute

[Marauder]

Thanks for your help.
I reached out to Paul at Weep No More.  Turns out he co-owns a MSC, Oasis Aero in Willmar, MN, and has seen this exact issue on many Mooneys.  He recommends that when I see the problem again, that I pull the circuit breaker for the CiES senders, wait for a few seconds, then reset it.  He expects that this will cause the senders to report the proper amount of fuel.  Paul and his partner are still trying to get answers from CiES.
Ute

I’m curious how there is a breaker for the CiES senders.

As for the “magnetic” mode, what they are referring to is the frequency mode. Think of the difference between frequency and resistive as the difference between analog and digital.

I’m not sure how the Garmin is setup. My senders are using frequency mode. I found that the senders did not work correctly until I grounded them to the same ground point as the JPI 900. Also, I don’t know whether they specified it in the installation manual, but I used a shielded wire.

I put a thread out there documenting my installation. Might be helpful if you find it.


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[gotyacovered]

Hello friends.  My son, two friends, and I bought a '67 M20F a year ago.  We love her!  We just had a new all-Garmin panel installed and paid extra to mate the G3x with CiES fuel senders for accurate fuel levels.  We have O&N bladders from 1995.  We've flown for 35 hours since the panel upgrade and the levels have been spot-on except for 3 instances recently that incorrectly showed full fuel in a tank for the remainder of that flight.  Once in the left tank and twice in the right tank.  We sent the diagnostics file to the avionics shop and they verified that the sender reported that during the flight, the fuel level changed from about 18 gallons to 32 gallons, and stayed there.  These are all brand new senders, and it has now happened on both tanks.  The shop called CiES and they reported this is a known issue with certain bladders, something about the magnetism of the material that the bladder is made of reacting badly with the senders, and they get 'stuck', thinking the fuel level is full.  I sent an inquiry to Griggs Aviation (they purchased O&N) and asked if they were aware of the problem.  They responded this is the first they've heard about it.
Have any of you seen or heard of this issue before?  At this point, neither we nor the shop knows how to proceed, other than to not rely on the fuel gauges.
Thanks!
Ute
p.s. This is my first post, but have watched every thread now for a year.  I tried to find info that's already there and failed, with this being the closest thread: 
 

I’ve noticed that my 1976 F will occasionally ‘add’ fuel during a flight or sometimes not show the proper gallons for fuel burn. Mine has only occurred on one side… Look forward to following this thread.


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[DCarlton]

A little off topic but for the folks (and in particular the F's) with bladders, do you have the full 64 gal solution or the 50 gal solution?  Also, do you know of any experienced bladder installers out West?  Thanks.  

[rbp]

don't have bladders, but I will mention for a broader audience that the CEIS senders in my M required post-installation adjustment due to interference from the internal structures in the fuel tanks. 

[UteM20F]

On 12/22/2022 at 1:06 PM, Marauder said:

I’m curious how there is a breaker for the CiES senders.
...
I put a thread out there documenting my installation. Might be helpful if you find it.
 

The avionics shop that did our panel added a few of these breakers, including the one for the CiES senders.  We flew today and once again we didn't see the problem.

I'm looking forward to finding your installation thread.  I'm wondering how much extra we paid our shop for their lack of Mooney experience.

Ute

[UteM20F]

On 12/23/2022 at 10:03 AM, DCarlton said:

A little off topic but for the folks (and in particular the F's) with bladders, do you have the full 64 gal solution or the 50 gal solution?  Also, do you know of any experienced bladder installers out West?  Thanks.  

We have an F with the 64 gallon bladders.  They were installed in 1995.  Sorry, no experience with bladder installers, as the plane is still new to us.

After flying, we fill our tanks up to the tabs (20 gallons) in each wing.  It is surprising how long it takes for the fuel to drain into the other bladder.  Many times someone thought they had filled the tanks appropriately, then the next guy to fly complains about there not being fuel to the tabs.  That is one of the reason we went with the better senders.  Now we add fuel until the senders say 20 gallons in each side.  And everybody is happier.

[UteM20F]

On 12/23/2022 at 12:20 PM, rbp said:

don't have bladders, but I will mention for a broader audience that the CEIS senders in my M required post-installation adjustment due to interference from the internal structures in the fuel tanks. 

I'd love to hear what needed to be adjusted, as this sounds like the same problem we are seeing.  Any more information would be greatly appreciated, as our avionics shop is clueless about this issue.  

Ute

[carusoam]

We know a guy…

@fuellevel  (M20F customer questions…)

Our Ceis guy has been incredibly helpful over the years…

-a-

[UteM20F]

A quick update... @fuellevelresponded to me yesterday that they know what the problem is, and I spoke with CiES (Danielle) today.  CiES has resolved the problem in the software on the circuit board, and will update our senders when we send them in, and will overnight them back.

Interestingly, although we have 4 senders (2 bladders per wing), they only need the inboard sender from each wing.

As soon as we have a reason to have work done at that shop again, we'll have this taken care of.

Ute

[Echo]

Quick update. One year later?