EDM 900 owners

[Stephen]

I have an EDM 900 install that is exhibiting odd behavior with the Temp....and possibly other functions. Those of you that have one on an IO360 aircraft, could you possibly take a video of 2 scenarios so I can compare behavior for troubleshooting purposes?

1) Ground idle, 1K rpm, roll tape then switch on landing light and pitot heat. (My amperage draw bounces from 0-2 Amps and never stabilizes....it is constantly changing.

2) In flight level cruise (I used 2500/WOT and 9.2 GPG, ram air open at 6-9K feet-ish, but whatever you use will probably work). I'm mostly looking at RPM and Manifold reading stability. (mine dances all  around and never stabilizes within a 10th or two).

 

 

Thanks, I know this is a bit of a hassle, but we are months into troubleshooting this and JPI isn't being a huge amount of help so I think I need to narrow down the issue based on comparative, similar aircraft if at all possible. 

[ArtVandelay]

Bad ground connection or bad circuit breaker and/or power connection.

[JoshMan]

I also have the same issue and didn't really think anything of it.  Those with an EDM900- is your manifold pressure completely stable in cruise?

[Marauder]

3 hours ago, Stephen said:

I have an EDM 900 install that is exhibiting odd behavior with the Temp....and possibly other functions. Those of you that have one on an IO360 aircraft, could you possibly take a video of 2 scenarios so I can compare behavior for troubleshooting purposes?

1) Ground idle, 1K rpm, roll tape then switch on landing light and pitot heat. (My amperage draw bounces from 0-2 Amps and never stabilizes....it is constantly changing.

2) In flight level cruise (I used 2500/WOT and 9.2 GPG, ram air open at 6-9K feet-ish, but whatever you use will probably work). I'm mostly looking at RPM and Manifold reading stability. (mine dances all  around and never stabilizes within a 10th or two).

 

 

Thanks, I know this is a bit of a hassle, but we are months into troubleshooting this and JPI isn't being a huge amount of help so I think I need to narrow down the issue based on comparative, similar aircraft if at all possible. 

Why don't you download the data to Savvy Analysis and let them have a look? For item 1, although I haven't turned on and off stuff, I do see the amps fluctuate a bit at idle. 

As for item 2. If your MP is fluctuating a lot, there was an issue with the incorrect adapter and a firmware update to deal with it. I see a little fluctuation in flight. If it is moving wildly, I would be concerned. I do see the RPM move a few 10s of units (see below).

[JoshMan]

Red line is manifold pressure.  Its not terrible, but definitely fluctuates more than yours, Marauder

[Guitarmaster]

WHERE is the 900 grounded? Mine is on one of the vacuum pump bolts. It must be grounded to the engine.
I have almost zero fluctuation on any of my gauges once everything stabilizes.

Sent from my XT1585 using Tapatalk

[Marauder]

18 minutes ago, JoshMan said:

Red line is manifold pressure.  Its not terrible, but definitely fluctuates more than yours, Marauder

I'm pretty sure one of my JPI's return trips to JPI was to address the manifold fluctuations. Worth a call to find out if this could be a fix.

[JoshMan]

It is grounded to engine.  Will get it switched and see what happens.  Thanks, guys.

[carusoam]

Since you have the OAT challenge at the same time...

Grounding the engine and airframe and instrument panel may be of giant importance....

Some sensors and JPI require technical solutions to work properly...

MP, fuel P, and oilP are the ones I am thinking of... the raw data is oscillating and requires electric averaging or a device who's name escapes me tonight....

There are a few discussions on this topic. I believe @Bob_Belville might have some guidance....

Best regards,

-a-

[Bob_Belville]

8 hours ago, carusoam said:

Since you have the OAT challenge at the same time...

Grounding the engine and airframe and instrument panel may be of giant importance....

Some sensors and JPI require technical solutions to work properly...

MP, fuel P, and oilP are the ones I am thinking of... the raw data is oscillating and requires electric averaging or a device who's name escapes me tonight....

There are a few discussions on this topic. I believe @Bob_Belville might have some guidance....

Best regards,

-a-

I installed an EDM 930 about 5 years ago (IO360A1A). Anthony is referring to a "snubber" that JPI provided to dampen the pulsing of the MAP. The orifice restriction device installed in the line between the intake manifold and the MAP transducer and helped a lot in my case. I suspect that's been considered but if not it would be worth asking JPI about. 

[carusoam]

Bingo! Thanks Bob. 

It takes a community to overcome a small memory challenge. Go MS! 

Best regards,

-a-

[Stephen]

On 10/16/2017 at 8:34 PM, Guitarmaster said:

WHERE is the 900 grounded? Mine is on one of the vacuum pump bolts. It must be grounded to the engine.
I have almost zero fluctuation on any of my gauges once everything stabilizes.

Sent from my XT1585 using Tapatalk
 

It is grounded to the engine block I'll have to get the exact place. In the meantime here is a vid of my fluxuation in MP at stable, level cruise

IMG_3489.mp4

[Stephen]

On 10/16/2017 at 8:40 PM, Marauder said:

I'm pretty sure one of my JPI's return trips to JPI was to address the manifold fluctuations. Worth a call to find out if this could be a fix.

Thanks Chris, was kinda wondering if I had a system wide issue that was causing my OAT and manifold and Amp readings to be wonkey. I'll look into flying the $@&$ thing down to JPI to get it definitively fixed if I can't ID the issue. I can't get it to go above 2 AMPs will all switches on; it constantly bounces around from 0-2 at most. 

[DXB]

15 hours ago, Bob_Belville said:

I installed an EDM 930 about 5 years ago (IO360A1A). Anthony is referring to a "snubber" that JPI provided to dampen the pulsing of the MAP. The orifice restriction device installed in the line between the intake manifold and the MAP transducer and helped a lot in my case. I suspect that's been considered but if not it would be worth asking JPI about. 

I went through the same thing with my EDM900 MAP fluctuating when installed a couple years ago.  Definitely ask JPI about it, but don't expect them to be knowledgeable or helpful.  My process toward getting this issue fixed is outlined below.

Step 1. Based on Bob's experience, I call JPI and ask them if I need a snubber because it worked for Bob.  They said no -  I needed to have the unit removed and sent to them for a software update. I say nope - I ain't gonna do that.  

Step 2. I whine to my installer to see if they can get JPI to act reasonable. JPI then agrees to send a "software fix" to him to install.  I take off work to fly back to his shop.  This "software fix" does nothing to help. 

Step 3. I talk to the JPI CEO in their booth at Oshkosh. He says there's no software fix and that I need a snubber and to please call their tech support folks  so they can send me one.

Step 4.  I call JPI tech support and try to explain that their CEO wants them to send me a snubber.

Step 5. I take the received snubber back to installer, only to find that it doesn't fit on the JPI MAP transducer.  

Step 6.  I call JPI asking for a snubber that fits.  They said no such snubber exists and that I need to find an adapter.

Step 7. I look through snubber manufacturer's catalog to find that JPI is correct on there not being one that's threaded to directly fit their MAP transducer. 

Step 8: I call JPI to explain that it's their flawed MAP transducer that it doesn't fit, so can they please just send me the correct adapter for the snubber or at least give me a part number.  They said nope - I'm on my own. 

Step 9: I beg the installer to find the correct adapters for both ends of the snubber so it fits in the MAP line. Bingo! Problem solved.

Hopefully my experience can help you cut out at least a couple of steps.  But when you call JPI, please do not mention my name - I am not popular there, and they will likely hang up on you 

[Stephen]

On 10/16/2017 at 7:37 PM, JoshMan said:

I also have the same issue and didn't really think anything of it.  Those with an EDM900- is your manifold pressure completely stable in cruise?

DXB  thanks for the intel....I posted a video of mine above .... is that what you were seeing?

 

Bob and Anthony thanks also. I'll ask JPI for a snubber. 

[DXB]

8 minutes ago, Stephen said:

DXB  thanks for the intel....I posted a video of mine above .... is that what you were seeing?

 

Bob and Anthony thanks also. I'll ask JPI for a snubber. 

Yup - that was basically my problem - annoying, isn't it?  I think your magnitude of fluctuation is a bit greater than mine was though.  

[Stephen]

4 minutes ago, DXB said:

Yup - that was basically my problem - annoying, isn't it?  I think your magnitude of fluctuation is a bit greater than mine was though.  

Yeah ... basically 10ths are useless. JPI has been good (for what works) but also Very expensive and frustrating. 

[Bob_Belville]

7 hours ago, DXB said:

I went through the same thing with my EDM900 MAP fluctuating when installed a couple years ago.  Definitely ask JPI about it, but don't expect them to be knowledgeable or helpful.  My process toward getting this issue fixed is outlined below.

Step 1. Based on Bob's experience, I call JPI and ask them if I need a snubber because it worked for Bob.  They said no -  I needed to have the unit removed and sent to them for a software update. I say nope - I ain't gonna do that.  

Step 2. I whine to my installer to see if they can get JPI to act reasonable. JPI then agrees to send a "software fix" to him to install.  I take off work to fly back to his shop.  This "software fix" does nothing to help. 

Step 3. I talk to the JPI CEO in their booth at Oshkosh. He says there's no software fix and that I need a snubber and to please call their tech support folks  so they can send me one.

Step 4.  I call JPI tech support and try to explain that their CEO wants them to send me a snubber.

Step 5. I take the received snubber back to installer, only to find that it doesn't fit on the JPI MAP transducer.  

Step 6.  I call JPI asking for a snubber that fits.  They said no such snubber exists and that I need to find an adapter.

Step 7. I look through snubber manufacturer's catalog to find that JPI is correct on there not being one that's threaded to directly fit their MAP transducer. 

Step 8: I call JPI to explain that it's their flawed MAP transducer that it doesn't fit, so can they please just send me the correct adapter for the snubber or at least give me a part number.  They said nope - I'm on my own. 

Step 9: I beg the installer to find the correct adapters for both ends of the snubber so it fits in the MAP line. Bingo! Problem solved.

Hopefully my experience can help you cut out at least a couple of steps.  But when you call JPI, please do not mention my name - I am not popular there, and they will likely hang up on you 

I had forgotten your saga. I guess that sometime after my experience (August 2013) JPI got tired of providing free snubbers and set up a "stall and maybe they'll go away" procedure. I do remember that the snubber connection was a mismatch (the only snubber they had was NPT, the transducer is AN) and I had to find a fitting(s) to do the install. I'm pretty sure the snubber wound up in the line but not right at the transducer. However the fix did work.

[N6758N]

 

4 minutes ago, Bob_Belville said:

I had forgotten your saga. I guess that sometime after my experience (August 2013) JPI got tired of providing free snubbers and set up a "stall and maybe they'll go away" procedure. I do remember that the snubber connection was a mismatch (the only snubber they had was NPT, the transducer is AN) and I had to find a fitting(s) to do the install. I'm pretty sure the snubber wound up in the line but not right at the transducer. However the fix did work.

I tried getting them to provide a snubber and they acted like they had no idea what I was talking about. They suggested checking connections, etc...after about three years I sent mine back for the CiES sender hardware modification, and supposedly they fixed the software issues that cause the MAP fluctuation as well. Hoping to fly it this week to verify it. 

[Bob_Belville]

5 minutes ago, N6758N said:

 

I tried getting them to provide a snubber and they acted like they had no idea what I was talking about. They suggested checking connections, etc...after about three years I sent mine back for the CiES sender hardware modification, and supposedly they fixed the software issues that cause the MAP fluctuation as well. Hoping to fly it this week to verify it. 

Terry, this is a note from my avionics shop dated 7/2013. This was the resolution after numerous exchanges trying to eliminate electrical noise etc. To me, their language clearly implies a problem they'd rather not have to properly solve. 

"JPI looked at all your data (including the last one) and they think the sensor is just a little to sensitive for your aircraft. They are sending us a dampener for the sensor. I haven't had to use one yet but they say they have had to put a dampener on a couple other aircraft with similar indications."

[Guitarmaster]

I went through the same thing with my EDM900 MAP fluctuating when installed a couple years ago.  Definitely ask JPI about it, but don't expect them to be knowledgeable or helpful.  My process toward getting this issue fixed is outlined below.
Step 1. Based on Bob's experience, I call JPI and ask them if I need a snubber because it worked for Bob.  They said no -  I needed to have the unit removed and sent to them for a software update. I say nope - I ain't gonna do that.  
Step 2. I whine to my installer to see if they can get JPI to act reasonable. JPI then agrees to send a "software fix" to him to install.  I take off work to fly back to his shop.  This "software fix" does nothing to help. 
Step 3. I talk to the JPI CEO in their booth at Oshkosh. He says there's no software fix and that I need a snubber and to please call their tech support folks  so they can send me one.
Step 4.  I call JPI tech support and try to explain that their CEO wants them to send me a snubber.
Step 5. I take the received snubber back to installer, only to find that it doesn't fit on the JPI MAP transducer.  
Step 6.  I call JPI asking for a snubber that fits.  They said no such snubber exists and that I need to find an adapter.
Step 7. I look through snubber manufacturer's catalog to find that JPI is correct on there not being one that's threaded to directly fit their MAP transducer. 
Step 8: I call JPI to explain that it's their flawed MAP transducer that it doesn't fit, so can they please just send me the correct adapter for the snubber or at least give me a part number.  They said nope - I'm on my own. 
Step 9: I beg the installer to find the correct adapters for both ends of the snubber so it fits in the MAP line. Bingo! Problem solved.
Hopefully my experience can help you cut out at least a couple of steps.  But when you call JPI, please do not mention my name - I am not popular there, and they will likely hang up on you 

Wow.....

Sent from my XT1585 using Tapatalk

[Marauder]

JPI is pretty good at denying problems until you squeeze them. This issue was caused by RF interference created by the remote fault indicator (not the sensor I call it in the video). Final resolution was to put a ferrite filter (like what find on a computer power cable) on the indicator’s lead.

Sent from my iPhone using Tapatalk Pro

[DXB]

Once the OP's issue gets fully addressed, perhaps this thread can live on as the go to place for everyone to therapeutically bitch about JPI customer service. 

Don't get me wrong - I love my EDM-900 now that all the bugs are shaken out, but the other significant issue I had with it turned into every bit as much of a PITA to get fixed.   

[RLCarter]

Not sure if this has been asked or not..... Has the issues  been there since the install, or have they popped up slowly over time? Is this an owner installation, owner assisted, or shop installed? 

[carusoam]

The MP snubber issues go back as far as 1965.  

As in the Mooney parts manual shows a snubber in the line with the MP gauge. Find the page that covers all the instruments in the instrument panel and check the part numbers list...

MP is a very noisy thing to measure. Air is a very compressible material, naturally.  Four intake valves opening and closing add to the fluctuations.

A snubber is just a small restriction in the line, to smooth it out, without accidently altering it.

Another oddity Of old MP gauges is The calibrated tiny weep hole. This keeps the blue goo from evaporated 100LL from getting all the way to the gauge each time the engine shuts down.

I wouldn't expect JPI to be handing them out for free. 

The oscilation occurs in a frequency that could be digitally smoothed out. Look how fast a JPI can collect data... it is not fast enough to digitally smooth out the MP.  It collects data every two seconds, the prop rotates faster than that.

I would expect JPI to recommend a proper snubber for purchase, with proper plumbing fittings.

Their tech guys should know this. Maybe they aren't motor heads.

The computer guys don't know that their computer is too slow to collect proper data for digital smoothing. They must be seeing random highs and lows, not all of the highs and lows.  Hard to do an average when the data looks random...

You would think an engine instrument company would have a motor head in there somewhere. Find an engineer that likes to tweak the engine in his car. He will know programming, MP and ignition curves... His Audi will have Uber turbos and the power output will have been measured on a dyno, strapped down operating at full speed.

Too high a price paid to not get the bits and advice you need.

Send JPI to MS. We can coach them regarding what their customers need. 

Best regards,

-a-