Bad tach...should I go GI 275 EIS?

arnoha

arnoha

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arnoha
My A&P just declared my tach junk. I've got a steam gauge 172S. Looks like the a direct replacement SLI model is about $800 plus another $120 or so if I want to set the tach number to match the old one.

I've been toying with the idea of putting in an EIS of some sort for a while. The GI 275 wasn't an option until recently, but its features and price jump it to the head of the line. Anyone have experience with this yet?

I know the GI 275 is about $4,000. The engine kit is about $1000. The temp probe, should I want it, is around $500. I have no idea what labor would run...anyone know around how many hours an install should take?

I have CiES fuel senders already on this aircraft. I have a pair of G5's, but no temperature probe for them. Can the temp probe be shared? They seem to be different part numbers. Having a forest of temp probes on the aircraft seems silly. Even if I need different adapters, can the probe itself be shared?

EDIT: Guess another option is the EI R-1. $450, with no fee to set the tach time. But it's a 2" gauge, not a 3", which is a little annoying. Anyone have experience with this one?
 
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I'm guessing minimum $4000 install. My guess seems high to me, but install costs always seem high to me. You won't know for sure until somebody looks at your specific situation. @Jesse Saint

Temp probe can't be shared.
 
Find a used digital Horizon somebody's pulling because it's incompatible with electronic ignition.
 
arnoha said:
My A&P just declared my tach junk. I've got a steam gauge 172S. Looks like the a direct replacement SLI model is about $800 plus another $120 or so if I want to set the tach number to match the old one.

I've been toying with the idea of putting in an EIS of some sort for a while. The GI 275 wasn't an option until recently, but its features and price jump it to the head of the line. Anyone have experience with this yet?

I know the GI 275 is about $4,000. The engine kit is about $1000. The temp probe, should I want it, is around $500. I have no idea what labor would run...anyone know around how many hours an install should take?

I have CiES fuel senders already on this aircraft. I have a pair of G5's, but no temperature probe for them. Can the temp probe be shared? They seem to be different part numbers. Having a forest of temp probes on the aircraft seems silly. Even if I need different adapters, can the probe itself be shared?

EDIT: Guess another option is the EI R-1. $450, with no fee to set the tach time. But it's a 2" gauge, not a 3", which is a little annoying. Anyone have experience with this one?
Click to expand...

Had one of those (EI R-1) in my previous airplane. Worked great. Simple install. Easy to read even at 2"
 
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Chip Sylverne said:
Find a used digital Horizon somebody's pulling because it's incompatible with electronic ignition.
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Interesting option. Hadn't seen that one before. I see many on eBay for around $250.

Thank you. I'll keep it in mind, but there's a complication on my plane: it's a leaseback. The small price difference to the new EI unit will result in more than that amount of spurious squawks for the weird and kinda ugly Horizon unit.
 
Chip Sylverne said:
Find a used digital Horizon somebody's pulling because it's incompatible with electronic ignition.
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We have the P-1000 in our plane, it works just dandy and is easy to read. I'd bet you can find a good used one on ebay.
 
EdFred said:
Had one of those (EI R-1) in my previous airplane. Worked great. Simple install. Easy to read even at 2"
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Arrgh. I just looked and the 172S is not on EI's STC and AML. Does that pull this off the possible choices?

The damn AML hasn't been updated since 1997!
 
Email em, might just be filing some paperwork.
 
EdFred said:
Email em, might just be filing some paperwork.
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Yeah, maybe. Probably still wouldn't help me...it's a leaseback, so spending the extra $500 on the Superior one makes sense to get it back on line now instead of a month from now when the paperwork comes through.
 
arnoha said:
Interesting option. Hadn't seen that one before. I see many on eBay for around $250.

Thank you. I'll keep it in mind, but there's a complication on my plane: it's a leaseback. The small price difference to the new EI unit will result in more than that amount of spurious squawks for the weird and kinda ugly Horizon unit.
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Ain't weird and ain't ugly. The red warning led's in case of a mag failure is a beautiful, beautiful thing. So are precise mag drop readings. Operates 7-31 volts.
 
Chip Sylverne said:
Ain't weird and ain't ugly. The red warning led's in case of a mag failure is a beautiful, beautiful thing. So are precise mag drop readings. Operates 7-31 volts.
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Sorry, that came out rougher than I intended. It looks fine to me, and seems to work well. I'm just channeling my inner renter. Experience has taught me that different without really obvious benefit (like my G5s) gets a plane less interest and fewer renters. Either way, I appreciate you bringing this one to my attention. May not be the right answer for this plane, but might be a good answer for my next plane, which will likely be personally owned.
 
arnoha said:
Arrgh. I just looked and the 172S is not on EI's STC and AML. Does that pull this off the possible choices?

The damn AML hasn't been updated since 1997!
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Have you considered a CGR-30P or EDM900?
 
N1120A said:
They fixed that
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Really! Can the fix be retrofitted, or is it just on new units? If it's a retrofit, that's great news. One day I'm going to get a Surefly, and keeping my Horizon would be a bonus.
 
Really the value proposition is about how much your own money is worth to you, and how much you'll enjoy that GI 275.

You can replace a basic tach in a fixed-pitch prop airplane pretty easily. An "EIS" replacing an analog tach in an airplane like a C-172 offers little in the way of enhanced safety or utility -- my litmus test, usually, for panel upgrades. All you really need is a needle pointing to the correct RPM.

A multi-probe engine analyzer is always a very nice tool to have installed. It was one of the first upgrades in my Twin Comanche many years ago. Not sure I'd want to figure out a way to integrate the GI 275 as part of my scan knowing that I'd have to page over to the engine management page with a small RPM indicator on top. Might be more value in simply installing a multi-probe engine monitor/analyzer and leaving the tach the way it is?
gi-275-eis.jpg


That's mighty small for a tach... is it really an improvement? You'd have to be the judge on that.

I'd estimate $10k+ installed for that package. It's not a small job.
 
And just to add something, there's something to be said for having things because you want them. It's not really possible for me to "justify" airplane ownership in the first place, but I've owned one or more at significant expense for nearly 20 years. If you want it, and the enjoyment exceeds the value of the cash remaining in your pocket, get it.
 
Chip Sylverne said:
Really! Can the fix be retrofitted, or is it just on new units? If it's a retrofit, that's great news. One day I'm going to get a Surefly, and keeping my Horizon would be a bonus.
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It can apparently be retrofitted.
 
Regarding the EI R-1 tach, I never liked those much, the way the LEDs and digits bump in "discrete lumps" as you're trying to tweak RPM. RPM is one of those, to me, where an analog needle (or screen presentation of same) is more appropriate. But, then, I'm old enough to be an analog guy anyway, to each his own. And, not intended to be a slam on EI whatsoever, they make great products.
 
Aircraft Quality Instruments repairs mechanical and electronic tachometers...less than $200. Flyaqi.com
 
asicer said:
Have you considered a CGR-30P or EDM900?
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Yeah, those were the models I was most interested in prior to the announcement of GI 275 EIS, mostly the CGR-30P. The CGR-30P is a little cheaper, by about $1000, but the instrument selection is more limited. Spec'ing it out results in fewer other gauges leaving the panel. It's the same form factor, so the same issues with size and the screen is older and lower resolution. The EDM900 has a bigger screen, which is nice. Similar price. It's still tempting, as it has similar function to the GI 275, but a bigger screen. The Garmin has the advantage of blending into the panel better, interfacing with my mostly Garmin panel better, and being easier to use.
 
Doug Reid said:
Aircraft Quality Instruments repairs mechanical and electronic tachometers...less than $200. Flyaqi.com
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Yeah, not sure why a repair option wasn't presented to me by the A&P. I shall ask. If that's really just $200, that's a clear winner.
 
Ryan F. said:
Really the value proposition is about how much your own money is worth to you, and how much you'll enjoy that GI 275.

You can replace a basic tach in a fixed-pitch prop airplane pretty easily. An "EIS" replacing an analog tach in an airplane like a C-172 offers little in the way of enhanced safety or utility -- my litmus test, usually, for panel upgrades. All you really need is a needle pointing to the correct RPM.

A multi-probe engine analyzer is always a very nice tool to have installed. It was one of the first upgrades in my Twin Comanche many years ago. Not sure I'd want to figure out a way to integrate the GI 275 as part of my scan knowing that I'd have to page over to the engine management page with a small RPM indicator on top. Might be more value in simply installing a multi-probe engine monitor/analyzer and leaving the tach the way it is?
gi-275-eis.jpg


That's mighty small for a tach... is it really an improvement? You'd have to be the judge on that.

I'd estimate $10k+ installed for that package. It's not a small job.
Click to expand...

Ryan F. said:
And just to add something, there's something to be said for having things because you want them. It's not really possible for me to "justify" airplane ownership in the first place, but I've owned one or more at significant expense for nearly 20 years. If you want it, and the enjoyment exceeds the value of the cash remaining in your pocket, get it.
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Yeah, I figured $10K+. I've had basically the same advice that an EIS on a 4-cyl fixed pitch makes little sense. But...I've also had several engine issues that could have been caught earlier, possibly, by data logging. Since last overhaul, three cylinders have been replaced (one twice). Fuel injectors have fallen apart. P-leads have broken three or four times. Had a magneto fail. Would having an EIS help with all of these? Probably not, but particularly with the cylinder failures I could have a hope of determining why and what corrective action to take to avoid it in the future. I still don't know why those cylinders lost compression. (As in, zero or near zero. This was not a case of barely dropping below 60 and replacing to be conservative.)

Still, probably not pulling the trigger now. Maybe when the engine is overhauled in 300 hours.
 
Get a used tach or repair the one you have. If buying used make sure the hours are recorded correctly. IF/WHEN you get a full blown engine monitor just set that to the actual aircraft time you add up.
 
arnoha said:
Yeah, those were the models I was most interested in prior to the announcement of GI 275 EIS, mostly the CGR-30P. The CGR-30P is a little cheaper, by about $1000, but the instrument selection is more limited. Spec'ing it out results in fewer other gauges leaving the panel. It's the same form factor, so the same issues with size and the screen is older and lower resolution.
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I personally like that the EGT/CHT graph is on the main page of the CGR-30P vs down in the menu of a GI275. Renters may prefer the opposite, though.

arnoha said:
Yeah, I figured $10K+.
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I've been quoted ~20 hours.
 
arnoha said:
The CGR-30P is a little cheaper, by about $1000, but the instrument selection is more limited. Spec'ing it out results in fewer other gauges leaving the panel. It's the same form factor, so the same issues with size and the screen is older and lower resolution. The EDM900 has a bigger screen, which is nice. Similar price. It's still tempting, as it has similar function to the GI 275, but a bigger screen. The Garmin has the advantage of blending into the panel better, interfacing with my mostly Garmin panel better, and being easier to use.
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The Garmin sounds like a great solution for you then. The EDM900 is really in a different product category, IMO - The big square screen means cutting your panel, which means it's going to be more expensive. The CGR-30P was going to be my other suggestion, it's really nice for replacing a 3 1/8" tach. But it sounds like the Garmin's differences are worth the price difference to you, so it kinda sounds like your decision is made!

arnoha said:
Yeah, I figured $10K+.
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I think you might be able to come in under that. We were quoted $8200 (haven't gotten the bill yet, but the shop stuck to their quote last time) for the ADAHRS+AP version, where the instrument is more expensive. You'll need the sensor kit and installation may vary somewhat, but I bet $10K would do it.

I've had basically the same advice that an EIS on a 4-cyl fixed pitch makes little sense. But...I've also had several engine issues that could have been caught earlier, possibly, by data logging.
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I would disagree that it makes little sense. If used properly, a good engine monitor with data logging can be used both for trend monitoring and prediction of issues like you're talking about, as well as diagnosis after it happens. If I had a plane on leaseback, I'd put a logging monitor on it before I let anyone else fly it!

Still, probably not pulling the trigger now. Maybe when the engine is overhauled in 300 hours.
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While that may save you a little $$ on installation because things will be apart already, I would suggest you do it now so that you can get a baseline of data logged BEFORE the overhaul. We're already 100 hours over TBO and just put in a new engine monitor for that very reason.
 
flyingcheesehead said:
The Garmin sounds like a great solution for you then. The EDM900 is really in a different product category, IMO - The big square screen means cutting your panel, which means it's going to be more expensive. The CGR-30P was going to be my other suggestion, it's really nice for replacing a 3 1/8" tach. But it sounds like the Garmin's differences are worth the price difference to you, so it kinda sounds like your decision is made!

I think you might be able to come in under that. We were quoted $8200 (haven't gotten the bill yet, but the shop stuck to their quote last time) for the ADAHRS+AP version, where the instrument is more expensive. You'll need the sensor kit and installation may vary somewhat, but I bet $10K would do it.

I would disagree that it makes little sense. If used properly, a good engine monitor with data logging can be used both for trend monitoring and prediction of issues like you're talking about, as well as diagnosis after it happens. If I had a plane on leaseback, I'd put a logging monitor on it before I let anyone else fly it!

While that may save you a little $$ on installation because things will be apart already, I would suggest you do it now so that you can get a baseline of data logged BEFORE the overhaul. We're already 100 hours over TBO and just put in a new engine monitor for that very reason.
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Are you sure the panel needs to be cut for the EDM? I know it can be flush mounted, but it's round behind the panel and I believe it can be surface mounted. My G5s are the same...surface mounted.

Thanks for the info. My thinking is similar to yours, but...$10K or that region is a lot of money for what it is a small gain, ultimately. There's another gain, too...loss, actually. I'd drop some pounds from the gauges I could lose. And I could sell some of them.

Oddly, I could eliminate almost everything on the left, except that none of them have a clock! Not a big thing, but a bit annoying as my clock is also my ammeter and volts and OAT, which every other EIS covers. So it would be nice to lose.

EDIT: note, this is a vacuum-free plane, after the G5.
 
arnoha said:
Are you sure the panel needs to be cut for the EDM? I know it can be flush mounted, but it's round behind the panel and I believe it can be surface mounted.
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Ah, I was confusing the 900 and the 930. The 900 is really more like their 800 series only primary, the 930 and 960 are significantly larger. Technically even a 930 can be mounted in a 3 1/8" hole, but you need one with a lot of room around it which is pretty uncommon.

arnoha said:
Oddly, I could eliminate almost everything on the left, except that none of them have a clock! Not a big thing, but a bit annoying as my clock is also my ammeter and volts and OAT, which every other EIS covers. So it would be nice to lose.
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Well, if you have another instrument hole getting freed up somewhere, the Mid Continent MD93 is a very nice product, the flying club bought a plane that has one:

md93.jpg


But if you're buying a $10,000 tachometer, why not a $25,000 clock? :D

G3XTouch.jpg

(Along the bottom of the display, in the center, in case you missed it!)
 
flyingcheesehead said:
Ah, I was confusing the 900 and the 930. The 900 is really more like their 800 series only primary, the 930 and 960 are significantly larger. Technically even a 930 can be mounted in a 3 1/8" hole, but you need one with a lot of room around it which is pretty uncommon.

Well, if you have another instrument hole getting freed up somewhere, the Mid Continent MD93 is a very nice product, the flying club bought a plane that has one:

md93.jpg


But if you're buying a $10,000 tachometer, why not a $25,000 clock? :D

G3XTouch.jpg

(Along the bottom of the display, in the center, in case you missed it!)
Click to expand...

Oooh, I want that so much. I cannot justify it in the least for 172, but yeah...

As for the clock, that's a nice choice. Didn't realize that one existed. If I didn't already have 5 USB charging ports in the panel, it'd be even more tempting. Still, at $700 for a clock, I'd probably just leave the existing clock in place.
 
Oh, last item...anyone have experience with getting a ferry permit with an inop tach? Looks like if I'm doing anything other than a straight replacement, I'll likely need to go elsewhere. Would the FAA require something like a laser tach aimed at the back of the prop?
 
arnoha said:
IFR countdown clock to keep the plane IFR legal. Though it's possible that it exists and I missed it.
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FAR 91.205(d)(6) "A clock displaying hours, minutes, and seconds with a sweep-second pointer or digital presentation."

Doesn't say anything about countdown. CGR-30P has a clock and it displays hours minutes and seconds.

I suppose there's an argument to be made that a Davtron M803 doesn't satisfy that since it doesn't display seconds except when in timer mode.

Edit: BTW, a GPS can substitute for a clock:
https://www.faa.gov/about/office_or...2016/nkugba - (2016) legal interpretation.pdf
 
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asicer said:
FAR 91.205(d)(6) "A clock displaying hours, minutes, and seconds with a sweep-second pointer or digital presentation."

Doesn't say anything about countdown. CGR-30P has a clock and it displays hours minutes and seconds.

I suppose there's an argument to be made that a Davtron M803 doesn't satisfy that since it doesn't display seconds except when in timer mode.

Edit: BTW, a GPS can substitute for a clock:
https://www.faa.gov/about/office_org/headquarters_offices/agc/practice_areas/regulations/interpretations/data/interps/2016/nkugba - (2016) legal interpretation.pdf
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Perhaps... but read it carefully:

"Your second question asks if an installed appliance that has a clock presentation will suffice for a clock. Another installed appliance with a permanent clock display that meets the requirements of§ 91.205(d)(6) that displays "hours, minutes, and seconds with a sweep-second pointer or digital presentation," is adequate for the purposes of this regulation."

In other words, a "page" the pilot may navigate to somewhere on the "GPS" such as a Garmin 430 or GTN 650 won't cut it. However, the G1000's display, or G3X, etc. with a permanent clock display, would suffice.
 
asicer said:
FAR 91.205(d)(6) "A clock displaying hours, minutes, and seconds with a sweep-second pointer or digital presentation."

Doesn't say anything about countdown. CGR-30P has a clock and it displays hours minutes and seconds.

I suppose there's an argument to be made that a Davtron M803 doesn't satisfy that since it doesn't display seconds except when in timer mode.

Edit: BTW, a GPS can substitute for a clock:
https://www.faa.gov/about/office_org/headquarters_offices/agc/practice_areas/regulations/interpretations/data/interps/2016/nkugba - (2016) legal interpretation.pdf
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Interesting. That's what I get for running from memory instead of actually reading the regs. Also, nicely done remembering the Davtron model that is in my plane. I hadn't mentioned it in the thread, but you have it right.

So the question remains, as per @Ryan F. , does it count as permanent if it's on the main page but could be paged off of it? Either way, the CGR-30P doesn't work, as it appears the clock is optional as a main page function. I would like 7 primary gauges and the CGR-30P can only do 5, and that's not counting a clock. (L Fuel, R Fuel, Oil Pressure, Oil Temp, Fuel Flow, Volts, Amps...and RPM, but that doesn't count as one in CGR's count.) Interesting for the Davtron, as the timer functions can definitely be paged off of, but it counts as "permanent" somehow...but a GTN650 does not. Go figure.

The EDM is looking better and better. I'm surprised to learn, well, first how low the pixel counts are on everything and that the older EDM has the highest at 640x480. The well regarded GI-275 is only 480x433 (though on a much smaller display, so higher DPI, but alternately, round, so the total pixel count suffers). The G5 is a paltry 320x240. My search-fu is not rapidly finding the CGR resolution, but probably worse than the GI-275 in the same form factor.
 
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arnoha said:
So the question remains, as per @Ryan F. , does it count as permanent if it's on the main page but could be paged off of it?
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I think you just answered your own question, no?
 
arnoha said:
Also, nicely done remembering the Davtron model that is in my plane. I hadn't mentioned it in the thread, but you have it right.
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Thanks, but being a steam gauge 172SP it wasn't particularly difficult. :)
 
Ryan F. said:
Perhaps... but read it carefully:

"Your second question asks if an installed appliance that has a clock presentation will suffice for a clock. Another installed appliance with a permanent clock display that meets the requirements of§ 91.205(d)(6) that displays "hours, minutes, and seconds with a sweep-second pointer or digital presentation," is adequate for the purposes of this regulation."

In other words, a "page" the pilot may navigate to somewhere on the "GPS" such as a Garmin 430 or GTN 650 won't cut it. However, the G1000's display, or G3X, etc. with a permanent clock display, would suffice.
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By that definition, wouldn't it be the case that a Davtron M803 cannot be used as an IFR clock?

The M803 has a "page" the pilot may navigate to somewhere on the appliance (the pages being "UT", "LT", "FT", "ET") and does not have a "permanent" clock display.
 
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