What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Garmin Service Bulletin 2069 - Kavlico Pressure Sensor Inspection

g3xpert

Well Known Member
Advertiser
Good Afternoon,

In coordination with our industry partners and in response to a small number of field reports relating to leaking fuel pressure sensors, we have released Service Bulletin 2069, which includes guidance to review current sensor installations and take action if deemed necessary. We are continuing to look into the known occurrences, if the root cause is determined to be installation related we will further update our installation guidance, if it is found to be sensor related, we will take action to keep G3X customers safe and informed.

Drawing on our long history in both the certified and experimental aircraft markets, we have designed an inspection procedure to ensure that, under certain circumstances, fuel pressure sensors are not being exposed to excessive pressures due to thermal expansion within the fuel lines. The service bulletin contains further guidance for subsequent steps to be taken upon completion of the inspection procedure.

We would like to thank our industry partners for collaborating with us to address this issue, and as a group help to ensure no safety issues relevant to the fuel pressure sensors are being overlooked.

Please feel free to reach out to us with any questions.

Thanks,

Justin
 
Just read through this SB, but it doesn’t make sense to me. Return to service if everything checks out ok?? It could fail tomorrow or next week or who knows when. Why not just allow replacement if there is a known issue with them?
 
So...

My question is this:

I am getting ready for a first start. Should I replace the sensor first?

Have they made any changes to the sensor design to warrant pre-emptively changing it?
 
"...Have they made any changes to the sensor design to warrant pre-emptively changing it?..."

Yes, the SB's reference a new, much more robust design for around $85 each (you would probably need 2). They don't mention whether the improved design was undertaken as a result of the failures.

Retaining the old sensors after all the reports of failures would be rolling the dice on a potential in-flight fire.

So far I haven't seen any offers from the manufacturer to exchange the improved product for the flawed one, or at least provide the improved product at cost, similar to what Slick did with their magneto SB1-15A

So it looks like we're going to be out about $170 to get this fixed
 
I "did" the SB yesterday - mainly an inspection - but wondered the same thing.

My oil pressure is the -150 model, fuel pressure is the -50

But I don't think the new ones are even available yet, are they?
 
I "did" the SB yesterday - mainly an inspection - but wondered the same thing.

My oil pressure is the -150 model, fuel pressure is the -50

But I don't think the new ones are even available yet, are they?

What was your fuel pressure 5 min after a hot shutdown?
 
What was your fuel pressure 5 min after a hot shutdown?

I don't have the exact numbers in front of me (written down elsewhere), but shutdown was ~23psi, it went up 0.1 or 0.2 in the first couple minutes then steadily trended downward after that.
 
Service Bulletin Procedure

Just read through this SB, but it doesn?t make sense to me. Return to service if everything checks out ok?? It could fail tomorrow or next week or who knows when. Why not just allow replacement if there is a known issue with them?

Certain fuel system configurations are capable of producing pressures well beyond the normal operating pressures of the fuel system, in specific circumstances. The service bulletin procedure was designed to identify if this is happening in your aircraft.

We have been conducting in-house testing and found that the Kavlico sensors significantly exceed the listed pressure ratings, they exceed the FAA burst pressure requirements, and there are tens of thousands flying with over a decade of field service.

If you are uncomfortable using the sensor, we now offer the TSO?d version out of an abundance of caution (Garmin Part Number 011-04202-20). The old 50 PSI Kavlico is being replaced by the TSO?d Kavlico with a higher operating pressure of 75 psi sensor. The TSO?d 75 PSI has a published burst pressure of 600 psi, compared to 150 psi for the previous sensor. Each TSO?d sensor is also pressure tested by Garmin before being shipped to you. The testing includes a verification of the accuracy too.

We are constantly improving our systems and sharing new information to help customers make informed decisions about 3rd party sensors. We?ll take appropriate actions to keep G3X customers safe and informed. Improvements and safety updates are found in the latest release of the G3X Installation Manual, 190-01115-01.

Thanks,

Justin
 
Kavlico Fuel Pressure Sensors

"...Have they made any changes to the sensor design to warrant pre-emptively changing it?..."

Yes, the SB's reference a new, much more robust design for around $85 each (you would probably need 2). They don't mention whether the improved design was undertaken as a result of the failures.

Retaining the old sensors after all the reports of failures would be rolling the dice on a potential in-flight fire.

So far I haven't seen any offers from the manufacturer to exchange the improved product for the flawed one, or at least provide the improved product at cost, similar to what Slick did with their magneto SB1-15A

So it looks like we're going to be out about $170 to get this fixed

We have seen a very small number of failures of these sensors in the field. The G3X is compatible with a wide range of sensors, if out of an abundance of caution, you wish to move to a different sensor, Table 24-1 in the installation manual provides specifications for what types of sensors are compatible, as well as some specific sensors that can be used with the system.

Moving forward, the 50 PSI Kavlico is being replaced by the TSO?d Kavlico (Garmin Part Number 011-04202-20) with a higher operating pressure of 75 psi sensor. The TSO?d 75 PSI has a published burst pressure of 600 psi, compared to 150 psi for the previous sensor. Each TSO?d sensor is also pressure tested by Garmin before being shipped to you.

Thanks,

Justin
 
Thanks Justin.

Do you have a link to purchase the new 75PSI sensor?

Does it use the same connector / wiring as the current equipment?

Do you recommend any change to the oil pressure sensor as well, or just the fuel system?
 
Fuel Pressure Sensor Part Numbers

Thanks Justin.

Do you have a link to purchase the new 75PSI sensor?

Does it use the same connector / wiring as the current equipment?

Do you recommend any change to the oil pressure sensor as well, or just the fuel system?

Hi Thomas,

They do use the same wiring as the currently fielded sensors. You can purchase them through a Garmin Dealer using part number 011-04202-30 for the oil pressure sensor and part number 011-04202-20 for the fuel pressure sensor.

Thanks,

Justin
 
Kavlico sensor

I have the legacy sensors for oil & fuel pressure on my engine. Was concerned at first but no leaks since they were installed so I?m leaving them on for now. Advanced Flight Systems will have the new ones in stock in a week or so. I contacted Sansata Technologies in San Diego, the parent company. The new sensor should connect with the snap connectors on top to existing wiring harnesses.

From Sensata:

? This are using a Packard Metripack 150 connection, you should not have any issues connecting the new sensors with the existing harness.?

Regards
Aldo I. Vasquez
Field Application Engineer, North America ? Industrial Solutions



[email protected] || 619-252-7664 mobile
Sensata Technologies, 2320 Paseo de las Americas, Suite 201, San Diego, California 92154
 
My fuel pressure rose to a max of 49.1psi within 5 minutes after shutdown. Lycoming IO-360.

Checked mine today (IO360 Avatar servo), immediately after shutdown fuel pressure went to 45psi. Pushed the mixture back in and it immediately dropped to near zero and stayed there. My new procedure AFTER shutdown will be to go full rich mixture, then ICO. Seems to solve the pressure spike issue. Only thing I can figure is that this is due to the Avstar servos NOT incorporating a fuel return line. Anybody see this fuel pressure spike with return line systems?
 
AFP system with purge valve, pull the purge valve, engine stops, pressure goes to '0' with no engine flooding.
 
Last edited:
Hi Thomas,

They do use the same wiring as the currently fielded sensors. You can purchase them through a Garmin Dealer using part number 011-04202-30 for the oil pressure sensor and part number 011-04202-20 for the fuel pressure sensor.

Thanks,

Justin

Justin,

Can we use the alternative part numbers being referenced by AFS/Dynon with the G3X systems? Seems the new part numbers they are referencing have much higher burst pressure specs. Will the G3X sensor characterizations handle those as well as the TSO'd part numbers you reference above?

Mine are not leaking but if there is extra insurance to be had, I would swap em out as long as I knew the alternative is truly better from a temperature and burst pressure standpoint.
 
Last edited:
data point

I talked to Garmin and they are recommending the 75psig sensor (which is apparently TSO'd). Part number they gave me was 011-04202-20.

They said they could not comment on any of the other manufacturers recommendations but that the G3X was pretty lenient on what sensors could be used...

I was not able to find any of the P255-150g-e4a sensors that AFS recommends; I called them to see if they had any and they asked me what EFIS I was using. I told them Garmin and they said they only had a few and would not sell me one because my system is Garmin...saving them for the AFS customers.

I was able to find the Garmin 011-04202-20, though. Be careful, I kept getting contradictory info...for example, if you put that part number in the ACS website, it will give you the 50psig sensor, NOT the 75psig.

There are also the sensors such as the UMA version...
 
Actually

Actually the one that seems to be the problem is the 50 psig sensor.

Also, garmin is recommending the 75psig sensor. They would not comment on the p255 series recommended by afs. It would stand to reason that the p255 would work though as they all output about 0-5 volts
 
Some interesting data off my Lyc 390. While performing the Service Bulletin test, I logged the pressure for over 6 minutes after shutdown and observed a rise from 28 psi to just over 33 - all within spec. Engine had been flown for 30 minutes so everything was nice and warm.

However, on the next flight, at shutdown the pressure spiked immediately from 27.5 psi at shutdown to 37 psi at 10 seconds, 44 psi at 20 seconds and off-scale (50 psi) at 34 seconds.

This prompted me to download logs and I looked at shutdown data from 21 additional flights where I had some data after shutdown - times from 4 seconds to almost 2 minutes - many in the 20-30 second range. The highest pressure seen was 32.4 after almost 2 minutes (consistent with my service bulletin test) - several flights showed declining pressure before turning off the EFIS.

What does it mean?? Beyond my pay grade. But don't rely on a single test per the service bulletin, or at least monitor shutdown pressure regularly - there appears to be variability in results.

(I have a Precision Airmotive Silverhawk fuel injection system with an Andair boost pump.)
 
My RV7A with G3X Touch, bought all new in 2017, has this Fuel pressure sensor:
"494-30004-02:, Fuel Pressure (Injected), 1/8-27 NPT, 50 PSI"
I understand I'm not affected by the bulletin (different part number), but today I performed the test and, within 1min from shutoff, fuel pressure climbed from 20ish to above 50psi (above that it stopped showing any number, as if it was off-scale). Should I be concerned?
 
Back
Top