EDM 350 Fuel Quantity and Pressure

[SwampRat]

UPDATE: Issues resolved and questions answered. Please read Posts 9 and 10 below for details if you face a similar situation.

Hi all,

My first post, please be gentle if I have missed an important thread.

RV-4 with an XP-360 Plus, carbureted, resistive fuel senders

I installed an EDM 350 a while back and just now getting around to fuel quantity and pressure (yeah, old Vans gauges are sticking). I sent the unit in and had the board installed and got the P5 harness with it, but no P6 or P7 harnesses. Called them up and they said that the 790802 boxes are no longer required and the "new" P6 harness is not included in the upgrade cost to add the fuel stuff. And they want another $200 for what seems to be 4 wires and a molex male plug...

So my question is if anyone out there has fuel quantity installed WITHOUT the 790802 boxes and, if so, is the P6 harness just 4 wires and a plug? Is there any reason I shouldn't just run 20 gauge and terminate my own plug?

Question 2 is, of course, does anyone know of a market alternative to their 159935A (carbureted) fuel pressure sender? I think they want $370 for it and I'm feeling that's a bit steep.

This is not a slamfest on JPI. I've installed most other sensors and it's been in the plane for 3 years with absolutely flawless performance.

Thanks

Nick Altizer
N12AD

 

[rv8ch]

Welcome Nick!

I can't comment on the EDM 350 but since this is experimental aviation, I'd recommend selling those devices and installing something more capable, and a lot cheaper.

I have this installed in my aircraft, and while a bit more than the numbers you are talking about, it creates a core system around which you can monitor everything, and integrate it with a cheap EFIS.

https://grtavionics.com/product/eis-packages-for-lycoming-continental/

Of course you can get similar solutions from Garmin, Dynon, MGL, and a few others you can see advertised to your left on the screen.

You are just a short flight from lots of really smart RV people, and I guarantee someone like Mr. Pratt can hook you up with some excellent advice.

https://vansairforce.net/rvcentral.htm

 

[SwampRat]

Thanks Mickey!

Both for the welcome and some amazing information. And it couldn't come at a more appropriate time as I am weighing options for either replacing the iPad with an Aera 760 or installing a true EFIS - either way I will be cutting a new panel so yeah, the timing is right. I've seen Garmin and Dynon installations but I've seen nothing here in The Swamp at CXO with GRT installed. I will very seriously consider GRT as a third option. Briefly reviewed the documentation. I don't think we'd have any GRT compatibility issues with existing avionics, a GTR-200 and a GTX-345, though I believe a 10.1 would not work due to interference with a structural component behind the panel. The Sport would work.

I've seen mention of Mr. Pratt before but never realized he was so close! Looks like a mission is in order once I get the EDM back up and working (I have to do that before considering next steps, not flying the -4 is a horrible way to exist).

I love the interior of your -8. Everything you need, nothing you don't! Python much?

Nick
N12AD

 

[rv8ch]

...

I love the interior of your -8. Everything you need, nothing you don't! Python much?
...

Thanks Nick. I'm extremely happy with my -8 and my little GRT EFIS Sport, and you'll probably hear exactly the same from every builder, no matter what EFIS they put in. Thankfully for us the competition is very intense in that market and all the suppliers seem to be creating some very nice products.

Another great source of info on selecting an EFIS is SteinAir (https://www.steinair.com) - they have seen everything multiple times, and can provide good advice based on exactly what you have today, and your mission.

My day job unfortunately does not require slinging code any more, but from time to time I dabble to keep the whippersnappers on their toes. They're shocked when they see someone over 30 write something useful.

 

[SwampRat]

I believe the issue with EDM 350 Fuel Pressure has been resolved. Short story is that the P5 harness now includes a 2-wire bundle that is labeled VDO FP or something similar. This is not shown on the drawing on page 18 of the install, but is shown on the P5 schematic on page 45. So, duh, I hooked them up to my old VDO 360043 sender and configured the EDM accordingly, and it worked. Not sure why JPI is telling me I need their expensive sender, but my bad was focusing on the clearly outdated drawing over the clearly updated schematic. Given that the old 360043 sender is as old as the airplane, I have a new one on order ($64) and will post confirmation once installed.

Update on fuel level perhaps as early as today if I don't slide off an iced over bridge.

 

[jneves]

Keep us posted Nick, thanks for the info so far.

 

[SwampRat]

Sorry for the delay. It's been rather cold here and I managed to get sick as well.

I don't have firm data yet as nothing is in final form, but:

1. Fuel Pressure: As I stated, the old VDO 360043 sensor works. The new 360043 arrived the day I got sick so I have not installed it yet.

2. Fuel Tank Level: Ran wires and temporarily inserted them into the JPI Molex plug. Was able to fake "calibrate" fuel and it worked fine. I haven't yet done a permanent wire install nor a proper calibration but by all appearances we just need to splice the sender grounds together and connect the sender wires to the P5 harness (Right sender goes to white, left sender goes to green, grounds go to black), then calibrate using JPI protocols.

I promise to update with final results once airborne, but everything looks promising.

 

[jneves]

Nick did you purchase the JPI P5 connector and harness or make on of your own?

Also what fuel senders do you have on your plane?

 

[SwampRat]

Howdy Johnny,

I purchased the basic EDM 350 and had to send the unit back to JPI to have the mux board installed for the fuel levels, fuel pressure and second ammeter. If you have two holes on the back, then you don't have the fuel board. The J5 connector will attach through the stbd hole and the warning light connector will attach through the port hole. When you get the board installed, they WILL send you the P5 harness, but not the P6 harness that extends to the wing tanks unless you ask and pay for it. The conditioner, 790802, is no longer required for resistive senders (confirmed) nor capacitive senders (per documentation).

My RV uses resistive output type senders.

Updates:

Installed the new VDO 360043 fuel pressure sender and the reading is 4.5 PSI with fuel pump running - perfect. My old sender was definitely tired.

Snipped off the FQ1/FQ2 molex plug (J6 in the drawing) and soldered the fuel level wires to the harness as described in this mornings post. All looks good. Will try to calibrate in the next few days.

 

[SwampRat]

Fuel levels and pressure are installed and tested. All work well.

Fuel Pressure:
I'm using a VDO 360043 pressure sender and read between 4.5 and 5.5 PSI in flight without the electric pump on. The EDM is responsive when engine stopped and I hit the electric pump switch, quickly rising from 0 to about 4.5 to 5.0 PSI. Perfect.

Fuel Levels:
I ran wires to the tanks soldered to the harness as described previously. Once I turned on fuel levels the EDM recognized without a hitch. Calibration was quick, simple and accurate. Fuel levels are responsive and accurate in the air. The P6 harness by JPI is unnecessary if you don't mind running your own wiring.

Now a problem with oil pressure:
I believe this is unrelated (at least directly) to fuel, however after I got the EDM back from JPI for the J5 upgrade my oil pressure reads double what it should. Wondering if this is the result of a firmware update they might have done after the PCB was added. I posted that on the relevant thread below.
https://vansairforce.net/community/showthread.php?t=200686 Post 16

 

[jneves]

Fuel levels and pressure are installed and tested. All work well.

Fuel Pressure:
I'm using a VDO 360043 pressure sender and read between 4.5 and 5.5 PSI in flight without the electric pump on. The EDM is responsive when engine stopped and I hit the electric pump switch, quickly rising from 0 to about 4.5 to 5.0 PSI. Perfect.

Fuel Levels:
I ran wires to the tanks soldered to the harness as described previously. Once I turned on fuel levels the EDM recognized without a hitch. Calibration was quick, simple and accurate. Fuel levels are responsive and accurate in the air. The P6 harness by JPI is unnecessary if you don't mind running your own wiring.

Now a problem with oil pressure:
I believe this is unrelated (at least directly) to fuel, however after I got the EDM back from JPI for the J5 upgrade my oil pressure reads double what it should. Wondering if this is the result of a firmware update they might have done after the PCB was added. I posted that on the relevant thread below.
https://vansairforce.net/community/showthread.php?t=200686 Post 16

If I recall the setup menu allows changes to the sensor being used. I found it in the install manual, cant locate it now.

 

[SwampRat]

Good morning Johnny!

Yes, there are three choices under the Factory menu: VDO; Kavlico; Baystar. I selected VDO. Unlike Fuel Pressure, there is no menu option to select pressure range, which makes sense.

Troubleshooting included the following:
1) Select Kavlico and restart, then reselect VDO.
2) Select Baystar (I think that is what the name was) and restart, then reslect VDO.
3) Reset unit to Factory Settings, Config Only. Reconfigure all options on restart. Note: If you do this, remember you need to fire up the fan in front before the tach sensor will appear on the screen.

The results were consistently maddening, LOL. But they were consistent: I still read 2x actual pressure. I will perform a couple more steps, including playing around with a multi-meter (a friend found some good info on what to expect somewhere) as well as swapping out the sender.

Failing all that, I am not terribly interested in sending the unit back to JPI, which is the only option they gave me. I know for a fact that the firmware was updated as it is one version later than an friends 350, and he only got his about 3 months ago. This is my best guess as to cause. So I dug out my old Van's Oil Pressure gauge and will stick it in where my G-Meter sits, and just relabel the breaker.

I'm fairly done with JPI at this point and have been lusting after the G3X for a while now, so perhaps this fall I will take the plunge. rv8ch got me restarted on that with his post about GRT. But with all the Garmin stuff I already have installed, adding a G3X seems to be the most straightforward path with the fewest variables. And the screen! It's just...so...big!

 

[jselvatici]

Help Needed - JPI and Capacitive Fuel Probes

Howdy Johnny,

I purchased the basic EDM 350 and had to send the unit back to JPI to have the mux board installed for the fuel levels, fuel pressure and second ammeter. If you have two holes on the back, then you don't have the fuel board. The J5 connector will attach through the stbd hole and the warning light connector will attach through the port hole. When you get the board installed, they WILL send you the P5 harness, but not the P6 harness that extends to the wing tanks unless you ask and pay for it. The conditioner, 790802, is no longer required for resistive senders (confirmed) nor capacitive senders (per documentation).

My RV uses resistive output type senders.

Updates:

Installed the new VDO 360043 fuel pressure sender and the reading is 4.5 PSI with fuel pump running - perfect. My old sender was definitely tired.

Snipped off the FQ1/FQ2 molex plug (J6 in the drawing) and soldered the fuel level wires to the harness as described in this mornings post. All looks good. Will try to calibrate in the next few days.

Hello All,

Recently purchased EDM-900 and now I'm in the battle of fuel level calibration.

Before I had EI FL-2C fuel quantity indicator with capacitive fuel probes as per plans. Worked flawless.

With the EDM-900, JPI sent me the P7/J7 Box (PN: 791802) setup as CFG 3 (9.0 Volt - Pennycap/Gull). Installed everything as per print and when I turn the EDM-900 on for raw data verification to calibrate the tank, the numbers are "frozen" for LH and RH tank, I mean, they vary +/- 1 and that's it, no matter if the tank is empty or full.

If I disconnect the connector at the tank, it goes to NA.

Anybody had similar situation using JPI and Capacitive probes?

PS.: for test, I disconnected the box and ran the P6 harness direct to my RH tank for test, but no readings either.

Tried to call JPI but their customer support has left for the day... need to call tomorrow morning.

Appreciate the knowledge sharing.