Tach, now MP/FF gauge...when to give-in...

455 Bravo Uniform

455 Bravo Uniform

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455 Bravo Uniform
So I’ve had my tach placarded as reading 150rpm low during one of my annuals.

I scrubbed a flight yesterday due to the manifold pressure gauge now acting erratically, getting that looked at next week. That’s the Cessna dual gauge that also shows fuel flow on the right side.

So at what point do I just suck it up and install an engine monitor, that is the question...and I’m looking at a possible new prop at annual in August. $$$. Ouch.

Is there one gauge out there that just does RPM, MP, and FF? Or do they all also come with CHT & EGT functions? Or maybe I can put in separate digital replacements...

I’d rather not replace my analog gauges totally with a new “primary all replacement” as I like the redundancy in case a fancy screen goes dark (personal preference/opinion).

Don’t spend my money...
 
Go over to aerospacelogic.com and check out their gauges. I’ve got their Tachometer/Manifold Pressure Guage. It’s a good unit, easy to install. With that, you’d have to add a separate FF gauge.

I’m not sure you’ll find a Tach-MP-FF all in one without getting into a full engine monitor.


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I think your in JPI EM-730 (or equivalent) territory. You can keep the other stuff for reference and then your just need to keep your sticky notes on the "usual" difference between it and your old roundies.
 
455 Bravo Uniform said:
So I’ve had my tach placarded as reading 150rpm low during one of my annuals.

I scrubbed a flight yesterday due to the manifold pressure gauge now acting erratically, getting that looked at next week. That’s the Cessna dual gauge that also shows fuel flow on the right side.

So at what point do I just suck it up and install an engine monitor, that is the question...and I’m looking at a possible new prop at annual in August. $$$. Ouch.

Is there one gauge out there that just does RPM, MP, and FF? Or do they all also come with CHT & EGT functions? Or maybe I can put in separate digital replacements...

I’d rather not replace my analog gauges totally with a new “primary all replacement” as I like the redundancy in case a fancy screen goes dark (personal preference/opinion).

Don’t spend my money...
Click to expand...

put in aJPI and never look back. I would have never paid the money to upgrade until I flew with one. When I got my current Mooney it had one already in and I was swept off my feet. A worthwhile upgrade.
 
Time for a CGR-30P baby! Electronics International for the win! Or, do their separate electronic gauges. Roughly $450-$500 each plus install...
 
thomasdr72 said:
Time for a CGR-30P baby! Electronics International for the win! Or, do their separate electronic gauges. Roughly $450-$500 each plus install...
Click to expand...

I called EI. Though their FF gauge has an aux channel that can display MP (or many other single options), it’s not certified as a primary replacement for MP (or FF, which in my case is actually FP). Bummer, as that would have been a great solution.

“Experimental 182P, holding short, ready for departure...”
 
thomasdr72 said:
Time for a CGR-30P baby! Electronics International for the win!
Click to expand...

Your plane is speaking to you. I second the CGR–30P. My opinion you will get your money back in extended engine life will be on TBO managing accurate RPM, MP, CHT, EGT altogether.
 
MBDiagMan said:
put in aJPI and never look back. I would have never paid the money to upgrade until I flew with one. When I got my current Mooney it had one already in and I was swept off my feet. A worthwhile upgrade.
Click to expand...

Which do you have? I'm going 900 or 930 depending on panel space next year.
 
455 Bravo Uniform said:
I called EI. Though their FF gauge has an aux channel that can display MP (or many other single options), it’s not certified as a primary replacement for MP (or FF, which in my case is actually FP). Bummer, as that would have been a great solution.

“Experimental 182P, holding short, ready for departure...”
Click to expand...

I think maybe you asked the wrong questions... Their CGR-30P Premium looks like it should be usable as primary for all of the above: https://iflyei.com/product/cgr-30p-premium/

In any case, they do make good individual gauges if you want to go that direction, too.

Ravioli said:
I think your in JPI EM-730 (or equivalent) territory. You can keep the other stuff for reference and then your just need to keep your sticky notes on the "usual" difference between it and your old roundies.
Click to expand...

The EDM 700 and 800 series are not primary replacements - You need the EDM-900 to serve as a primary instrument. That is another option here.

Given @455 Bravo Uniform 's desire to have individual instruments, the Aerospace Logic stuff makes a lot of sense. $1830 for one tach and one combined fuel & manifold pressure. Nice.
 
flyingcheesehead said:
The EDM 700 and 800 series are not primary replacements
Click to expand...

If he's not removing the current, he doesn't need to put in one that is "also" primary.

Perhaps I worded my suggestion poorly.

From the original post:
455 Bravo Uniform said:
I’d rather not replace my analog gauges totally with a new “primary all replacement” as I like the redundancy in case a fancy screen goes dark (personal preference/opinion).
Click to expand...
 
flyingcheesehead said:
I think maybe you asked the wrong questions... Their CGR-30P Premium looks like it should be usable as primary for all of the above: https://iflyei.com/product/cgr-30p-premium/

In any case, they do make good individual gauges if you want to go that direction, too.



The EDM 700 and 800 series are not primary replacements - You need the EDM-900 to serve as a primary instrument. That is another option here.

Given @455 Bravo Uniform 's desire to have individual instruments, the Aerospace Logic stuff makes a lot of sense. $1830 for one tach and one combined fuel & manifold pressure. Nice.
Click to expand...

This is what I called them about:
https://iflyei.com/product/fp-5l-fuel-computer/

Thanks for the info on Aerospace Logic, I had no idea.

Only difference I see is that my gauge shows FF even though it’s a FP gauge (the only “issue” being that the Aerospace gauge only shows FP). I like the gauge calibrated to show FF.

9BD59E4C-D7DB-46C8-9287-5D25854BF773.jpeg
 
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The gage pictured shows fuel flow. Almost all fuel flow gages are calibrated to fuel pressure. The gage only indicates fuel pressure at the extreme lowest and highest ends of the gage...not actually calibrated for pressure anywhere else on the gage. The 24 is gph, not psi.

If you are interested, AQI, Aircraft Quality Instruments, repairs gages...give them a call if you wish.
 
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Clarified for @Salty

I believe @Mtns2Skies should have/had the same stock gauge in his Skywagon (IO-470-F?).

Thanks @Doug Reid and everyone who responded here.

A&P getting the costs and timing of repair vs refurb. Burnin’ summer flying days...and IR training.
 
I've got an MVP-50 which displays just about everything and will flash a big yellow (or red) light in front of you if any of them exceed limits.
 
MBDiagMan said:
put in aJPI and never look back. I would have never paid the money to upgrade until I flew with one. When I got my current Mooney it had one already in and I was swept off my feet. A worthwhile upgrade.
Click to expand...

930. Love it!
 
A common misconception (NOT helped by the manufacturer) is that the original gauge that we all rely on to show us fuel flow Isn’t actually a fuel flow gauge. It is actually a fuel pressure gauge that taps a sensing line off of the flow divider—but it happens to have a calibrated scale that shows the fuel flow rates that should correspond to the pressure range sensed at the flow divider.

However, there are many problems with this:
#1: if you have a partially blocked injector(s), then it will show an erroneously high flow reading (higher pressure than normal at the flow divider).
#2: if you have replaced your injectors with an aftermarket “tuned” set (GAMI), than your flow Scale is likely not correctly calibrated anymore either...

Now think of you the pilot might respond to scenario #1, maybe running the engine too lean at high power settings?

Either way, installing an instrument that actually show you the real flow has been the first recommendation I’ve given every owner I’ve helped. (It’s actually more important than a bar graph analyzer, IMO). Statistically, you are at a higher risk of running out of gas than cratering your engine... (Don’t get me wrong, an engine analyzer is the very next thing I’d install)...

V/r,

-Dana
 
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