Which engine monitor?

[PaulB]

I currently have a JPI 700 with FF in my '82 J and plan on upgrading to something more modern.  I've been looking at the 730, 830, and 900 but can't decide.  Does anyone have any thoughts on the usefulness of having MP/RPM on the monitor (830) or being able to remove the stock gauges all together (900).  I have room in my panel for any of them but I'm not sure if all the bells and whistles are worth the added expense.  

 

The 730 would give me the more modern look I'm going for as well as the ability to see all the parameters at once but it doesn't look like the 830 is that much more money and gives me a little more info.  On the 900, getting rid of the old stock gauges would be nice and it would be cool to have the differential fuel remaining in each tank but it would likely cost a lot more with little return.  Thoughts?

[PaulB]

Whoops wrong forum.  Can someone move this to avionics?

[DaV8or]

Seriously, don't just limit your choices to JPI. Check out what EI offers as well. I went whole hog and ditched all the factory gauges and added monitoring capabilities the airplane never had before. I love it and have no regrets. Of course there is always a budget to consider...  

[PaulB]

Seriously, don't just limit your choices to JPI. Check out what EI offers as well. I went whole hog and ditched all the factory gauges and added monitoring capabilities the airplane never had before. I love it and have no regrets. Of course there is always a budget to consider...  

Will the existing probes work with both systems or do you have to replace the whole set if you switch companies?  I'll take a look at EI in more detail.  Haven't really thought much about them yet since I figured it would add a lot of cost.

[N601RX]

I had an 830 and liked it. I replaced it a few months ago with a 900. The 900 gave me functional fuel gauges and allowed me to remove all the old stuff and clear up some panel space. It also got the fuel and oil line out from behind the panel. I checked the jpi part numbers between the 830 and 900 and found that many of the sensors and a couple of the wiring harnesses were the same, so I didn't have to replace everything. Jpi also sells a upgrade that swaps out the 700 display for a 830 display. I think it is usually around $1200. Check all the major mail order avionics places durring Oshkosh. Regardless of which model or brand you decide on, you will save several hundred $$$ durring the week of the show.

[laytonl]

I recently went though this decision process. I considered upgrading my 700 to either the 730, 830, or 900.

Ultimately I decided on the 700. Here are the factors that got me to the 730.

1. I wanted redundancy so a failure of either the factory gauges or the electronic display wouldn't leave me grounded.

2. I already have a digital tach, so the 830 didn't offer me much value.

3. I don't need digital MP because I don't really use MP. I run WOT except for descent and landing. I only use three MP numbers, 15" for landing, 16" for approaches, and 19" for 90kts level flight.

4. I don't need %HP, all I need to see is 2500 rpm on the tach.

5. I would have liked to have fuel levels, but didn't want to pay for it.

6. I liked the ease of migrating from the 700 to the 730. It took me less than 8 hours to do the install including managing to rouse my mechanic and get him to come over to the hanger and sign the 337 (and grumble about the fancy digital stuff!). The time involved was due to running wiring for the OAT, OT, and OP, and converting my Hoskins FF to the 730.

All that said, my hanger neighbor, Bob Belville, has either the 900 or the EI equivalent and it's really cool!

Good luck with your decision.

Lee

[Bob - S50]

Not sure, but I've read (maybe even on this forum) that any unit that is approved for primary reference such as the 900 will not allow you to program your own warning parameters.  For example, on the 730 or 830 you might choose to set a CHT warning for 400F but on the 900 you might be stuck with a factory limit of say 450F.  Same could be true of all other parameters.  Worth looking into as part of the decision process.

 

Bob

[ArtVandelay]

Not sure, but I've read (maybe even on this forum) that any unit that is approved for primary reference such as the 900 will not allow you to program your own warning parameters.  For example, on the 730 or 830 you might choose to set a CHT warning for 400F but on the 900 you might be stuck with a factory limit of say 450F.  Same could be true of all other parameters.  Worth looking into as part of the decision process.

 

Bob

Yes, this is true, JPI I believe is going to introduce 2 sets of alarms, factory and customized, and are awaiting approval.

[PaulB]

Thanks for the input everyone. Right now I think I'm leaning toward the 830 as the upgrade cost from the 700 is about the same for both the 730 and the 830. The 900 is several thousand more and I don't know there's much of an advantage for me to remove the factory gauges. Maybe if I completely modernize my panel someday I will do that. Looked at the EI products as well. Their TSO'd monitor looks like it's got a superior user interface but it doesn't take much to beat the two button JPI interface. Problem again is he large cost difference with not much return...

[M016576]

I had an 830 in my old J, and anew ei CGR-30P in my missile.

The 830 puts everything on one screen, which I like. I feel like I'm switching pages a lot on the CGR-30P.

Other than that one detail- the EI CGR-30P is superior in every way. It also costs $1000 less and is certified as a primary replacement.

Do you still have to replace all the sensors and probes when moving up to an 830 from a 700/800? I'm pretty sure that used to be the case, but maybe that's changed. If you do have to replace everything- you may want to look at the CGR-30P again.

Edit- the CGR-30P drops all the data into an excel spreadsheet. The JPI has a proprietary file format that is opened through their own analyzer software. I like the JPI software- it's pretty nice, but I like the flexibility of being able to open my engine monitor data on any computer with excel on it, too. I'm fairly handy with making my own graphs using excel; but the JPI program is much easier to use visually.

Does anyone with an EI engine monitor have a free software for analyzing their data (other than the Savvy online charts that require you to upload it?)

[ArtVandelay]

Do you still have to replace all the sensors and probes when moving up to an 830 from a 700/800? I'm pretty sure that used to be the case, but maybe that's changed. If you do have to replace everything- you may want to look at the CGR-30P again.

No, all probes work and even the existing wiring harness works as is, 830 adds additional wiring. I added MP/RPM because I wanted everything in 1 spot for easy scan.

[Bob_Belville]

As Lee mentioned, I have a 930 in my '66E. I like it a lot. With an Aspen and a GTN750 I have very few elements in my scan. At cruise, with the GPS, the Aspen with GPSS, and a STEC50 flying the flight plan, I'm spending most of my time studying the 930. So much useful info. 

 

If you have original style fuel pressure, oil pressure gauges you have fuel and oil lines coming through the firewall into the cabin. Not a great thing. My 930 puts transducers on the engine side.

[PaulB]

As Lee mentioned, I have a 930 in my '66E. I like it a lot. With an Aspen and a GTN750 I have very few elements in my scan. At cruise, with the GPS, the Aspen with GPSS, and a STEC50 flying the flight plan, I'm spending most of my time studying the 930. So much useful info. 

 

If you have original style fuel pressure, oil pressure gauges you have fuel and oil lines coming through the firewall into the cabin. Not a great thing. My 930 puts transducers on the engine side.

 

 

Didn't they do away with the fuel line in the cabin in the mid 70s?  Seems like DMax posted about this on the MAPA list a while back but I don't recall.  Mine is an 82J.

[KSMooniac]

Didn't they do away with the fuel line in the cabin in the mid 70s?  Seems like DMax posted about this on the MAPA list a while back but I don't recall.  Mine is an 82J.

 

I believe it wasn't until 1978.  My '77J had fuel and oil pressure lines inside the cockpit...now they're on a workbench.  

[ArtVandelay]

BTW, the 830 (and probably 730 as well) have prompts on the buttons to tell you what they are now...helps a little

[PaulB]

BTW, the 830 (and probably 730 as well) have prompts on the buttons to tell you what they are now...helps a little

Thats a huge bonus.  I have to keep a cheat sheet in my plane for the 700.  I always hit the wrong one and have to start over.  Very frustrating.

[ArtVandelay]

Thats a huge bonus.  I have to keep a cheat sheet in my plane for the 700.  I always hit the wrong one and have to start over.  Very frustrating.

Glad I'm not the only one, the manuals come with 2 page Quick Reference Guide in the back, so get an electronic copy, print it out and laminate, instant cheat sheet, but there is an error in Step 4 of transfer data in memory, should be LF instead of Step, even they get confused.

[dcrogers11]

You might have your avionics shop check for pricing as there was a couple of factory rebates that I was able to get from JPI on the 900 and I'm not replacing or updating from their older eqquipment.  With OSH in full swing, there may be others as well.  I can't wait to see what I've been missing with my 50 year old tech here in a month when mine is up and flying.   

Don

[jlunseth]

I have the 930, we removed all the factory gauges and put the 930 on the pilot side panel.  Removing the factory gauges  created plenty of room.  I would highly recommend putting it on the pilot side.  With all the gauges consolidated (with the sole exception of vacuum, which the JPI's don't handle) and in the instrument scan, it has saved my bacon a couple of times.  When something goes wrong and a factory gauge tells you, it has taken awhile for you to get around to the gauge, so the problem has had a chance to grow.  With the engine monitor gauges in your scan, you see incipient problems immediately and can do something about it.  I have had two such incidents, one a loss of oil pressure and the other a failur of the alternator.  Both times I saw the problem immediately.

 

If you don't fly IFR/IMC, then it would probably not be as critical to know of issues.

 

You might look at the EI MVP-50.  I love my JPI, but the only thing that is not great is the fuel gauges.  It is not the JPI's fault, the problem lies with the accuracy of the senders in the tank.  EI offers a much more accurate sender, not cheap, and when I looked into it I was told it may or may not work with the JPI so I never got those senders.  The factory senders are a pain, and not very accurate.  I would look at the EI monitor if I had to do it over again, if only to get accurate fuel readings.  The MVP-50 also reads out vacuum.  It would be really nifty to have that in your scan in IMC, rather than perched over on the far right, as far from the pilot as possible.

 

The sensors that come with an engine monitor and all different from the sensors installed on you engine, they are better and more accurate, and most must be installed with the monitor.  The cost of the installation will be roughly equal to the cost of the monitor.  The redlines cannot be modified, you will be asked to provide a copy of your POH and they will use the values from the POH to set the redlines.  My JPI has a few values for which the manual does not have a redline, such as fuel pressure, and for those values you could probably negotiate with JPI or EI for what you want.  No negotiation is possible on the redline values in the POH though, the unit would then not be certified as primary.

 

I have to say, it was a real relief to get rid of the factory strip gauges.  In my aircraft they were all over the panel, and many were tucked under the top of the panel where they were not very visible.  They were not very good, or very accurate, just a sort of general notion of what the respective values were.

[Bob_Belville]

I have the 930, we removed all the factory gauges and put the 930 on the pilot side panel.  Removing the factory gauges  created plenty of room.  I would highly recommend putting it on the pilot side.  With all the gauges consolidated (with the sole exception of vacuum, which the JPI's don't handle) and in the instrument scan, it has saved my bacon a couple of times.  When something goes wrong and a factory gauge tells you, it has taken awhile for you to get around to the gauge, so the problem has had a chance to grow.  With the engine monitor gauges in your scan, you see incipient problems immediately and can do something about it.  I have had two such incidents, one a loss of oil pressure and the other a failur of the alternator.  Both times I saw the problem immediately.

 

...

The sensors that come with an engine monitor and all different from the sensors installed on you engine, they are better and more accurate, and most must be installed with the monitor.  The cost of the installation will be roughly equal to the cost of the monitor.  The redlines cannot be modified, you will be asked to provide a copy of your POH and they will use the values from the POH to set the redlines.  My JPI has a few values for which the manual does not have a redline, such as fuel pressure, and for those values you could probably negotiate with JPI or EI for what you want.  No negotiation is possible on the redline values in the POH though, the unit would then not be certified as primary.

...

I put my 930 in the right side panel. And I think that is where it belongs. There is an annunciator sub panel right above the Aspen, very much in the primary scan, that routinely shows RPM & MAP but flashes any alarms like low Oil pressure or electrical system discharge. When the JPI was installed the fuel level sensors were sent to Lock Haven and were reconditioned. They are now very accurate from about 10 gallons to empty. The M20E has only one fuel level sensor per side and the float is pinned to the top of the tank when the tank is full so gauges will not show a lower level until the sensor can move.

[fantom]

I put my 930 in the right side panel. And I think that is where it belongs.

True for YOU, your plane panel space, and your impressive avionics. I'm sure you agree it's not where the monitor belongs for all models or all pilots, Bob.

Thanks to all for the detailed and even handed reviews.

[Bob_Belville]

True for YOU, your plane panel space, and your impressive avionics. I'm sure you agree it's not where the monitor belongs for all models or all pilots, Bob.

Thanks to all for the detailed and even handed reviews.

Gary, sure, I was just offering another opinion based on different experience. My point was/is that "flight engineer" information is not primary for aviate/navigate/communicate so there is nothing on the left panel I would relegate to the outfield to make way for the 930, as wonderful as the 930 is. I am fascinated by the EDM and look at it a lot, but not very often when I'm hand flying the plane.

[Marauder]

Gary, sure, I was just offering another opinion based on different experience. My point was/is that "flight engineer" information is not primary for aviate/navigate/communicate so there is nothing on the left panel I would relegate to the outfield to make way for the 930, as wonderful as the 930 is. I am fascinated by the EDM and look at it a lot, but not very often when I'm hand flying the plane.

Me on the other hand, I'm a nervous hypochondriac and want it right in front of me!

[Bob_Belville]

Me on the other hand, I'm a nervous hypochondriac and want it right in front of me!

That panel ain't s 1955 Buick Roadmaster! The right side is still practically under your nose. My 696 is further away than the 930 and still easy to operate... with my left hand.    

[N601RX]

As long as you have a warning light or buzzer I don't see a problem with it being on the right side. The only time I've had a problem the warning light got my attention immediately and I looked at the engine monitor to see what the problem was.