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JPI 350 - Using a VDO Oil Pressure Sender Instead

jneves

Well Known Member
Randomly thought I'd ask the knowledge base on VAF.

I recently purchased a JPI EDM-350 with full capabilities, but only added RPM sensor to the 4 CHT and EGT probes that come with it. This gets me the wire harness for CHT/EGT as well as the one for RPM, MAP, and Oil pressure. I would not mind bringing over MAP and Oil-P to the EDM, but would rather not spend $270 for the JPI Oil-Pressure sensor.

My current Oil-P is taken on a 20 year old mechanical gauge that is fed from an off the shelf VDO sender (the $40 kind you can get at any auto parts store). These are tried and true senders with years of use.

My question (because JPI says no to everything)...
- Has anyone used any non JPI sensors with any success? Oil-P is what I'm interested in now, but any input on any sensors would be great since that will open up the possibility of expanding the JPI use and removing more of the analog gauges from the panel at a much lower cost.
 
Amazon?

This may be helpful
I looked at the on-line manual for your monitor.
From that it looks like the type of oil pressure sender/transducer the EDM-350 uses is 5 Volt solid state of a common sort. So an old style auto resistance type is not directly compatible.

However, I found several units of similar type to the factory unit that might work quite well.

There are several listed by various vendors on Amazon. Here is one:
https://www.amazon.com/AUTEX-Pressure-Transducer-Stainless-Compatible/dp/B00NIK98O8/

This one is rated for 125 deg C as are the others listed that provide that spec.
The install manual shows the oil sender mounted away from the engine and connected by hose - to reduce the heat the unit is subjected to, I assume.

Since these sensors are available, accurate, reliable, cheap, and easy to interface to glass, I wonder why your post was not swimming with responses? I'll await the avalanche of real experience reports.

Ron
 
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Did JPI change the type of oil pressure sender between the EDM 730 and the 350? The 730 uses a standard resistive sender. You can PM me for the details.
 
Did JPI change the type of oil pressure sender between the EDM 730 and the 350? The 730 uses a standard resistive sender. You can PM me for the details.

Yep, looks like it. The on-line install for the 730 shows the resistive can type with 2 connection posts, while the 350 is a 3 wire connector with 5 volts, ground and output.
Ron
 

Well, looks like they have made a change. The doc for the 350 on their website is updated to 2021 and shows a solid state 3 wire oil pressure sensor..

https://www.jpinstruments.com/wp-co...Install-350-Experimental-REV-A-7-10-21Joe.pdf

So, obviously two versions.

Would have to do some research to know what will work with what.

Ron
 
Very delayed in reply, sorry had to table some of this. I check my unit and I only have 2 wires labeled Oil P coming from the harness that came with the JPI 350. So I guess there are 2 options, but harness wise I have the older 2 wire VDO.

I'll pick up a VDO and hook it up to see what I get.
 
So this is interesting. I posted sort of a similar post yesterday about fuel quantity and fuel pressure, but I can answer this for you...sort of. TBH I read your post yesterday, but not carefully enough. Sorry about that.

I purchased and installed my EDM 350 in 2018. At that time I installed CHT and EGT (of course) but I also installed oil temp and oil pressure. I purchased both the temp and pressure senders from JPI (and I probably paid $270:mad:). The pressure sender was, I am sure, a 2 wire and I am also pretty sure it was VDO. The sender terminals were screw type and I recall simply crimping ring terminals. Naturally I took a number of pics of the entire installation and, also naturally, I did not take a picture of the pressure sender.

I am running out today to do some work on the EDM and quite conveniently, the top cowl is off. So later today I will follow up this post with a pic and as much information as I can gather for you.

It would be interesting to know why JPI decided that the old VDO oil pressure sender isn't good enough any more. In 3 years and 200 hours, it's worked spectacularly well in the -4.
 
Thanks Nick! Any info would be appreciated. I picked up a VDO from Amazon and it arrives Monday. Depending on your findings I may install completely or just hook it up and simulate some lite pressure to see what comes of it. My hope is that it will work and I can save a few bucks, if this holds true for temps options I’ll be delighted.

Heading for a trip up the coast today! Weather on the west coast has been GREAT the last few weeks.

Thank you again for the reply. I’m hoping by the time I get through the rest of the sensors I’m able to build a list of alternate sensors and share them here with all to use as they see fit.
 
You bet! I hope this will help. Yes, it is a VDO but I couldn't find a VDO part number (I actually peeled off the label but there was nothing underneath and there were no part numbers that I could find anywhere on the sender. That was interesting!

So I did what I could and snapped a couple of pics hoping it would help. The oil pressure is good for 0-150. It is two wire. Here you go. Sorry I couldn't find more info for you!
 

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Thank you Nick looks like I got the right one, they only have one model that is 150 psi two wire. Appreciate the effort to confirm.
 
The part number on a VDO sender is on the "nut" the number in BAR (standard sea level barometric pressure times a number). 5 BAR is aprox 75PSI.
NAPA lists 5 bar as 0 to 80PSI.

They come in either single post; using the case as ground or dual post, where one post goes to ground and the other is used as signal. I've had my best luck using the dual post with a dedicated ground.
 
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The part number on a VDO sender is on the "nut" the number in BAR (standard sea level barometric pressure times a number). 5 BAR is aprox 75PSI.
NAPA lists 5 bar as 0 to 80PSI.

They come in either single post; using the case as ground or dual post, where one post goes to ground and the other is used as signal. I've had my best luck using the dual post with a dedicated ground.

That's great info!

I grabbed all the info off the nut today. Don't know what it all means but I hope it will help:

Nut face 1: 0-2 bar
Face 2: 5.19
Face 3: 0-10 bar
Face 4: 32/14
 
Happy to report I installed the $40 VDO 2 wire oil pressure sensor and it worked perfect right away. fired up the EDM350 and it started looking for new sensor, it recognized the VDO and accepted it as valid. I fired up the engine on the original sensor and it measured just over 80 PSI on the mechanical gauge (cold oil, higher PSI). Shut down right away, moved the oil line over to the VDO, fired her up and there it was 83 PSI on the EDM!

For those that are interested I purchased the VDO 150 PSI (VDO 360430 150 PSI Pressure Sender) from Amazon, current price is $44. see photos below.

Next I'm moving on to Oil Temp, this one I do not thing I will find an alternate so it may just be a JPI sensor. Anyone have input on this one?
 

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Congrats! Let us know if you have any luck with oil temp. I've never seen an alternative to JPI but you never know.

So I have an interesting problem now. After I got my 350 back from JPI for the fuel (J5) upgrade, my oil pressure readings are exactly DOUBLE what they used to be. I used to run 82 PSI at power, now it shows 164. When at idle, I usually showed between 70 and 75, now it shows 140 to 150. I use the JPI oil pressure sender. Has anyone else seen that? What was your fix? I will run a ground just to see if that's the issue and report back.
 
EDM900 RPM Problem

Randomly thought I'd ask the knowledge base on VAF.

I recently purchased a JPI EDM-350 with full capabilities, but only added RPM sensor to the 4 CHT and EGT probes that come with it. This gets me the wire harness for CHT/EGT as well as the one for RPM, MAP, and Oil pressure. I would not mind bringing over MAP and Oil-P to the EDM, but would rather not spend $270 for the JPI Oil-Pressure sensor.

My current Oil-P is taken on a 20 year old mechanical gauge that is fed from an off the shelf VDO sender (the $40 kind you can get at any auto parts store). These are tried and true senders with years of use.

My question (because JPI says no to everything)...
- Has anyone used any non JPI sensors with any success? Oil-P is what I'm interested in now, but any input on any sensors would be great since that will open up the possibility of expanding the JPI use and removing more of the analog gauges from the panel at a much lower cost.


Hi jneves,

Do you mind share your experience with JPI RPM sensor?
Do you have the one that is mounted on the magneto?
If yes, where did you mounted?
I mounted mine where I had a black cap on and when turn on the engine, I get a red X indication on RPM.
Sent a picture to JPI and they said I mounted on the wrong location. Is not supposed to be mounted there.

From JPI "Your rpm sensor is probably in the wrong hole. Move to hole with no gears visible."

Any help is appreciated, since JPI is limited in resource at this moment.
 

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Sent you a PM, but here is a photo circling the 2 vent caps. If you are not getting RPM you will need to move the sensor to the other vent cap location. I made the same mistake during my install, of course it's going to be the more difficult location to get the sensor into.....
 

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Sent you a PM, but here is a photo circling the 2 vent caps. If you are not getting RPM you will need to move the sensor to the other vent cap location. I made the same mistake during my install, of course it's going to be the more difficult location to get the sensor into.....

Thanks Johnny, I will check that later today.

enjoying the communication channel here, do you have capacitive or resistive fuel probes?

I'm asking because I have Capacitive and being using EI FL-2CA, which was working. Then when installing the EDM-900, can't get it to work. Contacted JPI and we still troubleshooting. Wondering if someone here have EDM and Capacitive fuel probes. How they get the system to work.

People here are amazing knowledge. Thank you.
 
I have not hooked my fuel up yet, I have the resistive senders so I'm not able to comment, I'm sure others will chime in.
 
I have a friend looking to install a EDM 730. Will the VDO 150 PSI bought on Amazon (VDO 360430) by the guy above used for the 350 work on the 730?
Thanks
 
I have a big update on my post (post 8) from this thread. I got oil pressure working on my JPI. This is rather convoluted and very likely completely dependent on the EDM firmware version, so your mileage may vary.

Back story (briefly): Around the first of the year (2022) I sent my EDM in for the J5 add-on for fuel pressure and levels. While there, JPI updated the firmware (which I naturally don't have with me). Fuel install went perfectly, but when I cranked up, oil pressure indicated 2-2.2x what it should have been (like, 150-180 psi). JPI didn't want to really talk about it and just wanted me to send it back in. So I just went back to my old steam gauge for oil pressure.

Fast Forward to this past weekend: After studying the 2017 and 2021 install manuals for the millionth time, I realized that the ONLY relevant difference for harness J3 was that Pin 4 was now shared between the MAP and Oil Pressure sensors (both indicated as i2s sensors). Obviously, my EDM was updated to support the i2s sensors (foreshadowing). So I spliced into the wire for pin 4 (my J3 harness is the older version as shown in the 2017 manual) and ran the power wire to a cheap Amazon i2s 150 psi sensor (for testing only), changed the sensor to i2s on the EDM and cranked up ol' Betsy.

Boom! 52 psi idle, 77 psi runup and 82 psi WOT (all static). So all good! Now waiting for my Kavlico to be delivered tomorrow.

There is a lot to unpack here that I won't get into. Such as why did the old oil pressure sensor show high numbers, the 2022 diagram shows VDO oil pressure on J5 when I am pretty sure that is VDO fuel pressure (as memory serves, but I can verify at some point), why does JPI call out a 30 psi i2s sensor for MAP to replace the 60 psi Motorola sensor (more foreshadowing), etc.

But there is one more thing that slowed the process down. At least on my firmware version, my EDM would not recognize the called out 30 psi i2s sensor for MAP. At all, just a big X! Yes, checked all connections for continuity and pin 4 for power. My guess is that my firmware version does not recognize it even though i2s is a selection in the menu. So I ended up staying with the Motorola sensor. Ground run indicated that sharing power between the Motorola and i2s oil pressure sensor (per 2021 manual with both sensors being i2s) causes no deleterious effects.

So yes, it is kind of shameful that it took 6 full months for it to finally sink in what was happening. But I'm kinda slow that way. I will update this thread after switching to a Kav sensor and test flight.

UPDATE: I guess I've got 20 or 25 hours since this post. All functions work perfectly since adding the Kavlico sensor.
 
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JPI in general

Hello
Thanks for all who contributed to this thread. Lots of good info here.
As I am still waiting for the arrival of my new to me -4, I continue to explore panel options. After receiving a couple of quotes for a glass panel install, I may have to revisit options. But that leads me to the JPI product line.

The sensors discussions have been good reads.

How is JPI to deal with re customer service, turn around times, support, etc? It sounds like some members have had to find their own solutions to issues. Does that mean JPI customer/technical support is not great?
It sounds like changes to monitors ie adding sensors, requires the unit to be sent back to JPI? This may be troublesome for me being in Canada....don't know but will certainly add delays to whatever is normal.

Any input for me?
Thanks
Shawn
 
Hello
Thanks for all who contributed to this thread. Lots of good info here.
As I am still waiting for the arrival of my new to me -4, I continue to explore panel options. After receiving a couple of quotes for a glass panel install, I may have to revisit options. But that leads me to the JPI product line.

The sensors discussions have been good reads.

How is JPI to deal with re customer service, turn around times, support, etc? It sounds like some members have had to find their own solutions to issues. Does that mean JPI customer/technical support is not great?
It sounds like changes to monitors ie adding sensors, requires the unit to be sent back to JPI? This may be troublesome for me being in Canada....don't know but will certainly add delays to whatever is normal.

Any input for me?
Thanks
Shawn


I have had no issues with JPI the thread includes some questions, but my questions had nothing to do with JPI service and everything to do with wanting to save some money on sensors. I've spoken with JPI service a few times and have nothing bad to say. I'm sure they are not perfect, but they are good.

As far as sending back units for upgrade. This is done because some of us didnt order the full set of features we wanted, or we didn't understand the upgrade requirements to add sensors.

I'd strongly suggest you call JPI and have them help you configure your order and future proof the unit when you purchase. So example if you order from Aircraft Spruce you get the features in the software, but if you dont order the sensor, in some cases, you dont get the wires pinned to the connector. I ordered the full featured hardware but left out most sensor options. Adding Oil pressure was easy, bought the VDO gauge, plumbed and wired into the existing connectors that came with the unit. On the flip side, in order to add oil temp, I have to buy the sensor and wires and insert pins into the connectors, not a huge deal, but not easy to work under the panel either.

All in all I am VERY happy with the EDM350, small, easy to read, easy to setup. Their install manual is also very clear and easy to read/use.
 
Hello
Thanks for all who contributed to this thread. Lots of good info here.
As I am still waiting for the arrival of my new to me -4, I continue to explore panel options. After receiving a couple of quotes for a glass panel install, I may have to revisit options. But that leads me to the JPI product line.

The sensors discussions have been good reads.

How is JPI to deal with re customer service, turn around times, support, etc? It sounds like some members have had to find their own solutions to issues. Does that mean JPI customer/technical support is not great?
It sounds like changes to monitors ie adding sensors, requires the unit to be sent back to JPI? This may be troublesome for me being in Canada....don't know but will certainly add delays to whatever is normal.

Any input for me?
Thanks
Shawn

Welcome to the RV World!

I think Johnny parses many of your concerns accurately and offers very sound advice that everyone should follow should they take the JPI route.

As an observation, JPI appears to have introduced the EDM 350 as an inexpensive alternative to their certified products for those of us in the experimental market. Their business model, however, is the certified world and I believe that their support practices for the 350 align with that model. This is fine and probably best in the long term, however we need to keep it in mind as this may sometimes run contrary to certain freedoms in which we are accustomed.

I walked into the JPI world as a babe in the woods, ordering just what I needed at the time with the intention of adding other sensors and functions al la carte. As they say, it seemed like a good idea at the time. Yeah, don't. Their products are always evolving and with that, so is their firmware.

So would I recommend a 350? Or more telling, would I do it all over again knowing what I know now? Yes. The unit was then and is now rock solid. In the end, results are what count. My mistake was in "checking the boxes" during the order without taking the time to learn and understand JPI's architecture. Read through their latest install and user manuals until you know exactly what features you want, list any questions, then once again follow Johnny's advice before you order.
 
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