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Moritz Gauge Issue (Manifold Pressure)


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The Manifold Pressure Gauge on the Moritz cluster in my 2004 Ovation has quit.  My two main options appear to be upgrading my JPI 730 engine monitor to a 900 or installing an independent, primary Manifold Pressure Gauge.  

The installed cost of the independent gauge would appear to be about 10% of the cost of the 900.  There is room in the panel.

One risk of the independent gauge is what's next with the Moritz.

Any thoughts, comments, suggestions would be helpful.

Thanks

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Is it an absolute that the MP gauge itself is INOP or could it be the sending unit, a faulty wiring connection, etc.? I have an Eagle with the Moritz unit and each time I have had an issue with, what I thought was the gauges, turned out to be an issue back up stream like a wiring connection…

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1 hour ago, Aviator said:

The Manifold Pressure Gauge on the Moritz cluster in my 2004 Ovation has quit.  My two main options appear to be upgrading my JPI 730 engine monitor to a 900 or installing an independent, primary Manifold Pressure Gauge.  

The installed cost of the independent gauge would appear to be about 10% of the cost of the 900.  There is room in the panel.

One risk of the independent gauge is what's next with the Moritz.

Any thoughts, comments, suggestions would be helpful.

Thanks

I wouldn’t do the independent MP gauge. Once the Moritz gauges start failing it’s a domino effect.

All of your current JPI 730 CHT and EGT probes can be fed into the JPI900 or JPI 930. In fact I believe the connector on the back of the monitors are even compatible. An A&P can finish up an engine monitor install by installing the additional probes and wiring a lot cheaper than an avionics shop will do it and many owners assist in this project. @Aerodon can probably point you in the right direction.

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The MP gauge on the Moritz is a common failure point. We spent a lot of time trying to solve the problem and even used a Mooney schematic that utilized a replacement MP sensor. Nothing worked and 900 was installed. Having said that if you’re looking to save money used EI MP gauges are really cheap and there are tons of pulled Moritz head units rotting on shelves to solve problems down the road. 

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Second great memory award for MIm20c today!!! :)

There are even a few Moritz systems around here for sale lately…

JPI and EI have really good options for primary engine gauges…

JPI is more common…

EI is probably a better system… and has great customer support right on MS!

Garmin is coming up quickly with their EIS… and as a data collection device… the EIS is very powerful….

Best regards,

-a-

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16 hours ago, LANCECASPER said:

All of your current JPI 730 CHT and EGT probes can be fed into the JPI900 or JPI 930. In fact I believe the connector on the back of the monitors are even compatible. An A&P can finish up an engine monitor install by installing the additional probes and wiring a lot cheaper than an avionics shop will do it and many owners assist in this project. @Aerodon can probably point you in the right direction.

Are you sure about that?  JPI mentions that the 700 probes can be used to upgrade to a 730 or 830.   But I have not seen anything about using them for a 9xx.

OK, hear is what I found on Beech Talk:

"All of the CHT and EGT probes are the same and uses the same harness. You could just unplug the harness from the 700 and plug it into the 930. Here's the deal; per the STC you are supposed to change it all out. Seems crazy to pull out wires and replace them with identical wires, but that's what it says to do."

 

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7 hours ago, Pinecone said:

Are you sure about that?  JPI mentions that the 700 probes can be used to upgrade to a 730 or 830.   But I have not seen anything about using them for a 9xx.

OK, hear is what I found on Beech Talk:

"All of the CHT and EGT probes are the same and uses the same harness. You could just unplug the harness from the 700 and plug it into the 930. Here's the deal; per the STC you are supposed to change it all out. Seems crazy to pull out wires and replace them with identical wires, but that's what it says to do."

 

Common sense says that the harness and the wires that run through the fire wall can stay put. If the EGT probes have a lot of time switch them out where they mate up tp the harness near the cylinders. The CHT probes should be fine.

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As the quote states, the STC for the 9xx to be primary requires that you use the wiring and probes from the kit.  Even though they may be the same.

Up to you, your A&P, and your IA.  But technically, if you reuse the 7/8xx probes, your aircraft is not legal.

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11 hours ago, Pinecone said:

As the quote states, the STC for the 9xx to be primary requires that you use the wiring and probes from the kit.  Even though they may be the same.

Up to you, your A&P, and your IA.  But technically, if you reuse the 7/8xx probes, your aircraft is not legal.

If your IA makes you take the harness out and replace it with the exact same part number wire harness, it's not the wires I'd be concerned about replacing, it's the IA.

 

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15 hours ago, Pinecone said:

Even though the STC for the 9xx to be primary tells you that you have to change them?????

Perhaps one day when you actually take delivery of your airplane and start writing the checks you will understand how ridiculous it would be for any sane aircraft owner to pay good money to have the harness replaced with the exact same part number harness.

A great site to go to where they enjoy arguing about these types of things is Pilots of America. You would enjoy it over there.

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3 hours ago, LANCECASPER said:

Perhaps one day when you actually take delivery of your airplane and start writing the checks you will understand how ridiculous it would be for any sane aircraft owner to pay good money to have the harness replaced with the exact same part number harness.

A great site to go to where they enjoy arguing about these types of things is Pilots of America. You would enjoy it over there.

I understand that it makes no sense to do so.

But to be legal, you need to do so.

However, not sure if anyone could tell after the fact.

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On 7/28/2022 at 6:52 AM, Aviator said:

The Manifold Pressure Gauge on the Moritz cluster in my 2004 Ovation has quit.  My two main options appear to be upgrading my JPI 730 engine monitor to a 900 or installing an independent, primary Manifold Pressure Gauge.  

The installed cost of the independent gauge would appear to be about 10% of the cost of the 900.  There is room in the panel.

One risk of the independent gauge is what's next with the Moritz.

Any thoughts, comments, suggestions would be helpful.

Thanks

I have a used Moritz cluster and the manifold pressure transducer that I just pulled out of my 2000 ovation. Both were working fine when they were removed. If you’re interested, just make me an offer – I’d love to see them put a good use. Might be a good stopgap for you. They are listed under the used avionics group – I posted them a while back.

I also have the oil transducer which is why it’s in the picture as well. Cheers – Bob 

14186B3E-50FA-495E-A9BE-53338DC982DD.jpeg.b14bd83fb063a2ade28bbd3775d3f343.jpeg19DEC7AC-A56B-4B4D-8B71-AC097C54C576.jpeg.9cdfcfc13b029f7a6fd18ed1f95a65eb.jpeg

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11 minutes ago, jetdriven said:

for an altitude engine, is the ovation an altitude engine?

 

I think an "altitude engine" is one that is somehow boosted (as in turbocharged).  Also, in part 23 the requirement is "A manifold pressure indicator for each altitude engine and for each engine with a controllable propeller."  The emphasis is mine.  So, does that mean that a CAR3 airplane without turbocharger does not need a MP gauge?

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Let’s jump to the required equipment list in a handy M20R POH…

Hmmmm…

That’s odd, lots of dashes next to the Manifold Pressure!

Not required for anything…

but, it is possible to over MP your NA engine on cold days near SL…

Best regards,

-a-

:)

70C80D03-B57F-43EA-8614-7F8D9F3ECE53.jpeg

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  • 1 month later...

Well, it seems I am going to go the JPI or EI route.  Now my challenge is how to integrate into the panel on a 2004 Ovation.

I really do not want to put the unit on the right side out of my scan.  Suggestions and/or pictures of installations would be appreciated.

Thanks

IMG_20200428_103925.jpg

IMG_20200428_103932.jpg

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