M20C Panel Redo: EGT rotary switch too BIG.

[0TreeLemur]

I've embarked on a panel-redo, and I've hit a snag and need some advice.  

My 67C had a shotgun panel that featured an EGT gauge and 4-cyl selector right in the middle of the panel.  I plan to finish my IR this year, and want a six-pack instrument arrangement.  The a/c has a Radair 4-cyl EGT with a single gauge and a selector switch.  The panel mount rotary switch is 2-inches in diameter, about 2-1/4" dia. with wires attached.   It is in the middle of the photo resting atop the TC.  The single-channel EGT gauge itself is just below the AH.

Re-designing the panel to have a six-pack arrangement, with CDI and Dynon 2 EFIS between the six-pack and radio stack, the 2-1/4" EGT gauge must go to the left side below the key/master sw.  There is no place left for that huge selector switch because of its 2" diameter.   The switch is made by Shallco.  I also include a diagram of the new layout.

Any suggestions?   Does anyone have a smaller switch idea?   I assume that the red/yellow wires on the EGT are the dissimilar thermocouple wires and I need to be careful about cold junction error when selecting a switch.  I have been scouring the interwebs looking for smaller switches, but have not had any luck.  It seems that this calls for a 2-pole, 2-deck, 4 position switch.

Son #1 has access to a water-jet cutter and he is going to be cutting the new panel next week.  :-)

 

[Steve W]

It's not a cheap solution, but something like this?

https://buy-ei.com/portfolio/e-4/

Also, not sure you really need a 2 deck switch as long as it has 2 poles. I found this one by a quick search, not sure if this link will work:

https://www.mouser.com/ProductDetail/Grayhill/50K36-01-2-04N?qs=sGAEpiMZZMvNbjZ2WlReYhndqMY8foDIMRdXHx4tJsk%3d

In any case just go to Mouser.com -> Electromechanical -> Switches -> Rotary and put in your specs(4 position 1 deck with 2 poles or 2 deck with a a single pole each, panel mount, solder lug etc) and see what pops up.

[ArtVandelay]

The blank hole would be a great place for an engine monitor, lose the switch and the gauge.

[takair]

I have similar sized old school potentiometers mounted to a small bracket that is centered between the knees, hanging off the tubing.  It actually does not look too bad and is never in the way.  These switches are transferring very low current.  Not clear to me if they use Cromwell and alumel, but it seems to me they are optimized for the very low current.  You may or may not get away with an alternate switch.  Any junction does introduce error, but you are looking at relative EGT anyway, not absolute.

[N201MKTurbo]

You could make a bracket to mount the switch back behind the instruments with an extension shaft. All you would need on the panel would be enough room for he knob..

Why cant you mount the knob and maybe the gauge on the right panel?

Edited January 27, 2018 by N201MKTurbo

[Marauder]

I did what Takair suggests. Just make sure the local FSDO doesn’t have an issue with it.




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[0TreeLemur]

Takair's solution is what I'm leaning towards.   It seems like I could just leave it on the hottest EGT.  The blank hole will be covered by a Dynon D2.   We recently acquired this M20C, and focus is on maintenance/repair not upgrades at this point.   Most of the instruments have been sent for OH.  I've looked at the EI E-4, but 0.65 AMUs gets me a quarter of the way to an engine monitor that will go into replacing the tach on the right-hand side of the panel someday.

 

[carusoam]

FRED,

I may have missed something, but let me share something from my C experience...

 

Dump ancient engine monitor for decades newer modern technology...

The four selector switch is just a nightmare for pilot cog overload or a reason to ignore the data...

They invented the graphic engine analyzer for a reason.  It does all the switch turning, graphing, and delivers the results...

They also come with things like FF, flight recorder, and OAT...

They also have the ability to download data to somebody for help with an engine challenge...

even a decade newer used device doesn't cost very much...  even if you have to mount it in front of the copilot...

 

Climbing out... you have a significant engine vibration...  you look at the engine monitor and see one cylinder has gone cold...

You are in a much better position than dialing a switch waiting a few seconds for a steady reading, dial again, wait again....

This is the time you are landing straight ahead, and deciding if you have enough power to get to a field, or return to the airport you are leaving...

I got this stuck valve experience in the first 10 hours of mooney ownership.... no engine monitor.... had transition trainer on board...

Best regards,

-a-

 

[0TreeLemur]

Carusoam, thanks for the wisdom.  I'm re-thinking.  Not having had a failure, I don't think of them    Just like earthquakes- I've never felt one so they don't happen...  Need to consult my co-owner about expenditure.  Much appreciated.

 

[carusoam]

We have only had one earthquake lately in NJ... I can see how easy it is to ignore the possibility.  I was probably the first person out of the building in a proper fashion, while leaving, when it happened... after the fact, cell phones ablaze, we learned about what it was...

In a Mooney, There isn't much time to phone a friend... until after the root challenge is identified...

Having a single EGT would be fine if the hottest cylinder was the one that would fail...

But it is only showing one cylinder at a time... 

Graphically seeing all cylinders at a time allows you to decide how serious the engine problem is at a glance...

I lost one cylinder...

Losing a mag is sort of similar....

There are partial failures that remove some power when you would like to have it...

losing two cylinders, or the fuel system failing is going to be a short flight...

two things you want to avoid...

1) landing straight ahead when you don't need to...

2) Turning Back for the Airport when unable...

Being familiar with a good engine instrument, and having the data presented to you at a glance, while flying the plane may allow you a more informed decision...

What's the hesitation for modernizing your engine monitor?

Three things I wanted for my earlier plane...

• FF
• Carb temp
• four channel graphic engine monitor

Basically a well instrumented engine monitor.  Most of the data scanned during the T/O run... prior to committing to flight...

Carb temp is a nice to have when loaded to the max and you experience carb icing... it allows partial carb heat to allow more %HP than you get with the standard full carb heat response to an expected carb ice issue...

You won't know you have carb ice until you apply full heat, wait a large moment to have it clear out, or not... sense the time going by without being able to make an informed decision...

modern engine monitors allow informed decisions...

 

Some engine challenges like sticking valves are present for many hours before they get stuck.  Showing graphs to an engine monitor expert can help you determine things that you may not be able to see on your own...

That's What the Savvy guys are banking on... that's what a bunch of MSers do for fun...

My background... I'm an engineer that depends on instrumentation to fly a process that has no windows...

Best regards,

-a-

[N601RX]

A couple of things I learned several years ago when doing this. 

The steering shaft may hit the imstrument directly above it. 

Depth is a problem for the instrument on the bottom far left due to steel tubing

if using any kind of ring light extra clearance between instruments is required.

I don't think the egt is even required  

You can get a new color jpi 730 with 4 egt and 4 cht probes right now for around $1200. The other sensors can be easily added as money and time allows. Consider going ahead and removing the existing one to allow a little more cleanup of the panel.   I also prefer the key on the bottom just so it doesn't hang down on the instrument below. 

Another option is to put the existing switch on a separate small subpanel just above and to the side of your knee. 

[Guitarmaster]

Definitely lose the switch. Even a used engine monitor would be better than what you have.

I installed an EDM 900 and removed all the primary engine gauges a couple of years ago. This was probably the single best decision I made with the airplane!

Since you have the airplane apart already, it's the perfect time! Unfortunately, perfect time and perfect finances never align.

Your wallet might sting for a short time, but you will never regret installing a digital engine monitor!


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[0TreeLemur]

Thanks for your comment.  I'm comparing JPI vs. EI offerings.  Guitarmaster, did you get any of the options like fuel pressure, carb. temperature, or fuel levels?   Any recommendations/warnings?  I'm thinking about mounting the engine monitor in place of either the MP/FP or Tach, possibly getting rid of both.   Does the EDM900 have optional warning lights like the EI CGR-30P does?

[MIm20c]

1 hour ago, Fred_2O said:

Thanks for your comment.  I'm comparing JPI vs. EI offerings.  Guitarmaster, did you get any of the options like fuel pressure, carb. temperature, or fuel levels?   Any recommendations/warnings?  I'm thinking about mounting the engine monitor in place of either the MP/FP or Tach, possibly getting rid of both.   Does the EDM900 have optional warning lights like the EI CGR-30P does?

I have the 830 in my C that I find very useful. Mine has the oil pressure, oil temp, FF, OAT, IAT, TIT, tach, and mp sensors.  The TIT and IAT are needed for mine because of the turbo. I use my unit as my primary (meaning I reference it first) even though it is not certified as such.  However, all of my true primary gauges are installed and working properly. 

If you go the 900 route I’d splurge for the tank gauge and the fuel pressure just so you can get rid of the fuel past the firewall and clean up the panel. 

[Guitarmaster]

4 hours ago, Fred_2O said:

Thanks for your comment.  I'm comparing JPI vs. EI offerings.  Guitarmaster, did you get any of the options like fuel pressure, carb. temperature, or fuel levels?   Any recommendations/warnings?  I'm thinking about mounting the engine monitor in place of either the MP/FP or Tach, possibly getting rid of both.   Does the EDM900 have optional warning lights like the EI CGR-30P does?

The -900 came with MP, RPM, Fuel levels, oil temp, oil pressure, FP, FF, Volts and Amps, OAT, CHT, EGT and a host of other features.  It comes with Remote Alarm Light to be installed if the display is to far from the flight instruments.  There is an available Remote Alarm Display that will display WHAT is wrong, not just a light to get your attention.  
As others have said, when you feel a strange vibration or something seems a little off, it's nice to be able to pull the data and see if anything is amiss.

I have an "F" with an IO360 so no carb temp for me.  I believe it can be added if you want.

I liked the fact that I could replace ALL of my primary instruments.  It really cleaned up the panel.  

The problem with the CGR-30P I ran into was it didn't have enough inputs to cover all the primary instruments and I would have needed the 30C as an add-on making the EI offering unacceptable.
I LOVE the -900!  

Hope this helps!

As far as cost, I picked mine up at KOSH for $2795.  It took me and my IA about 45 hours to install.  It's not hard, but it's alot of wire pulling and connecting.

P.S.  I upload all my data to Savvy.  So far, I (they) caught a bad plug on #4.  It also showed my how far off my stock tach was.  I was only achieving 2550RPM.  It now turns 2700.  BIG difference on takeoff!  

Edited January 30, 2018 by Guitarmaster

[carusoam]

Some things to consider...

1) three manufacturers of modern technology...

• JPI expensive and un-nice service...
• EI expensive an friendly service...
• Insight avionics....

2) When looking to save space, you want the device to be qualified for primary instruments....

3) Read carefully some instruments are qualified for primary, but not for all of the functions... See @Guitarmaster‘s note...

4) if it’s not primary, you have a lot of original gauges that are kept whether you use them or not...

5) JPI has an interesting remote display called an RAD.  MP, rpm, and warnings displayed right in front of the pilot. All of the rest of the data can be put in front of the copilot for space.

6) Bob has an interesting M20E panel with a JPI, RAD, and an AOAi on his panel.... stuff to consider...

7) remember...

• original tach gauges have a tendency to fail every 50 years or so...
• oilP gauges bring an oil line into the cockpit...
• FuelP gauges bring a fuel line into the cockpit...
• the Map gauge, can spill a plethora of nothing all over the place.... 

8) FF And FL updates will ‘help’ keep you from running out of fuel... they can be connected to the GPS and flight plan to deliver fuel needed to get to your destination... and set an alarm if you aren’t going to make it... better than finding out when the fan suddenly gets quiet.

9) knowing an accurate OAT will keep ice off the wings, one knowledagble pilot required....

10) There is no extra instrument to keep a VFR pilot from going into IMC.  The MK1 eyeball is as good as it gets.  You probably have two.

Pp thoughts on instruments, not a mechanic...

Best regards,

-a-

  

 

[0TreeLemur]

carusoam and Mlm20C- excellent input- Thanks.

Guitarmaster- does the jpi use the existing fuel level sensors, or did you have to replace them?  I've read a few negative comments about that.  I do like the idea of removing old instruments for lots of reasons as mentioned above.

 

[Guitarmaster]

carusoam and Mlm20C- excellent input- Thanks.
Guitarmaster- does the jpi use the existing fuel level sensors, or did you have to replace them?  I've read a few negative comments about that.  I do like the idea of removing old instruments for lots of reasons as mentioned above.
 

It does use the existing fuel sensors, however it's only as accurate as your sending units are.
It will also use the CIES senders. @Marauder had these installed and found them to be highly accurate. At some point I want to replace my stock fuel senders with these!

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[ArtVandelay]

It does use the existing fuel sensors, however it's only as accurate as your sending units are.
It will also use the CIES senders. [mention=9886]Marauder[/mention] had these installed and found them to be highly accurate. At some point I want to replace my stock fuel senders with these!

You’ll need to send the JPI back, apparently only factory can set certain configuration parameters, like limits, etc.

[MIm20c]

55 minutes ago, teejayevans said:

You’ll need to send the JPI back, apparently only factory can set certain configuration parameters, like limits, etc.

You can adjust the parameters and limits for fuel levels in the setup menu. I think if you use resistance on the new senders they will work???

[Guitarmaster]

You can adjust the parameters and limits for fuel levels in the setup menu. I think if you use resistance on the new senders they will work???

If I remember right, you have to remove the little power boxes on the resistive senders when you use the magnetic ones. There should be no need to send it back to JPI. The only parameters that you cannot set are what's in your Poh. JPI sets all of your poh parameters, but you can adjust different alarms and your fuel tanks you calibrate.

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[0TreeLemur]

After lots of comparing, we have decided to install the JPI EDM-900.  After installing TSO'd Volt/Ammeter, will be able to eliminate cluster gauge, yielding space for Accutrak II if one is available.  Space above the cluster gauge will allow mount of IPad.  Thanks to everyone who provided input and advice.  Much appreciated.  Three week delivery to finish replacing pilot's side panel with six pack.

[Guitarmaster]

After lots of comparing, we have decided to install the JPI EDM-900.  After installing TSO'd Volt/Ammeter, will be able to eliminate cluster gauge, yielding space for Accutrak II if one is available.  Space above the cluster gauge will allow mount of IPad.  Thanks to everyone who provided input and advice.  Much appreciated.  Three week delivery to finish replacing pilot's side panel with six pack.

Good move! You're gonna love it!

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[Marauder]

After lots of comparing, we have decided to install the JPI EDM-900.  After installing TSO'd Volt/Ammeter, will be able to eliminate cluster gauge, yielding space for Accutrak II if one is available.  Space above the cluster gauge will allow mount of IPad.  Thanks to everyone who provided input and advice.  Much appreciated.  Three week delivery to finish replacing pilot's side panel with six pack.

That’s a good move. There is a lot of information packed into a modern engine analyzer.


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[carusoam]

Remember...

Before and after pictures are an MS tradition!  

Best regards,

-a-