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Engine Monitors

Part 1 of Engine Monitor Installations

Not all Engine Monitor installations are equal. A quality installation should be installed utilizing installation practices that are compatible with the surrounding compartments and the environment located within. The finished product should at minimum meet or exceed the OEM design criteria. Portions of this installation are protected from environmental elements inside the Aircraft Cabin, however, other portions are installed throughout the exterior Airframe and Engine compartment.

Special consideration due to the various surrounding areas should be taken into account but quite often don't, therefore installation practices will vary. Facilities specializing in Avionics can do a very clean installation under the Instrument Panel but tend to fall short regarding areas throughout the exterior Airframe and Engine compartment. The installer needs to consider vibration, movement, Turbo and Exhaust heat damage. Contamination from Fuels and Oils need taken into consideration. Additionally, solvents used for 100-hr Inspection cleaning and on-going maintenance, including major components or complete Engine replacement has it's effects over time. This items often lead to damaged wiring and premature failure of Probes and detailed components within the Engine Compartment. Your average Mechanical A&P, on the other hand, might utilize good practices within the Engine compartment. When it comes to Panel wiring however, fall short with things such as expansion loops and proper installation techniques lacking the quality crimping tools that are often found in the specialized Avionics shops. Very few A&P mechanics and Avionics Technicians are familiar with MIL-W-5088 [S/S by SAE-AS50881] that is utilized by all the Aircraft manufacturers in some form when your Aircraft was initially manufactured.

In fact, until recent years the FAA itself hasn’t given much thought to wiring standards until the introduction and rewrite of FAA AC43.13-1B. You can view various examples on the "Photos" link of proper and some “improper” installations found on various Aircraft.

With my involvement with such organizations as CPA (Cessna Pilots Association), CPS (Cessna Pilots Society) and other Cessna groups over the years as well as Manufacturers such as JPI, EI and Insight, I find that likely 90% or more of the Engine Monitor Failures or problems can be attributed back to installation errors.

A pilot will spend an equal value of the Aircraft itself with Glass Flight Displays and GPS features tied into an Auto-Pilot. These retrofit Aircraft could circumnavigate the Globe precisely, nearly without Pilot interface. It never ceases to amaze me that they have given no thought, nothing in regards to Engine Management to assure you can actually get there!

How much should I budget?

I found myself in a similar circumstance asking these questions with my 182Q. Initially I wanted to upgrade to a JPI EDM-830 which would have sufficed. Truth be told, the 830 is all that I really “needed”, however, I wanted to do something with the Instrument Panel as well. I was replacing the Center Stack with newer Avionics, modern Intercom System, XPDR and GPS so there was going to be extensive wiring behind the Instrument Panel. Either way I was removing obsolete equipment. With the old equipment removals there would be a "hodge-podge" of empty holes that would need covered somehow from Loran, ADF, old “GEM” Engine Monitor and a stand-alone Fuel Computer.

My MP was always off by 1” or more and RPM varied from 75-100 RPM at various engine settings The Factory CHT “single value” was useless and EGTs were non-existent. My Fuel Gage's “worked”, best I could tell. Flying in turbulence those wandering needles were a bit more uncomfortable to bear in unfriendly terrain then the ride itself.

In addition, I wanted full Fuel Computer management tied into the GPS. The parameters started to narrow down my path a bit more.

The Pilots Panel itself was going to remain mostly intact as finances would not allow a complete glass panel upgrade and really not necessary. Autopilot would be a higher priority versus Flight Instruments. For the time being, other then layout and overhauling those instruments, it would have to suffice.

Lastly, Joe Polizzotto from JPI made me an offer on a new EDM-930 that I couldn’t refuse, so it was obvious what direction I was going with this. Co-pilot side retrofitted with Panel Wedge for new Display complete and realignment of Pilots Panel instrumentation with a custom fabricated Aluminum Powder-coated Panel.

What Engine Monitor is best?

The best unit is one with good product support and that fits your budget and needs.

Choosing an installer that is familiar with the product line and experience with installations will help to keep the installation cost at a minimum. Don’t bargain hunt, such as “used” equipment. This often leads to a sub-standard installation that will have short longevity or frequent failures that eventually lead to dissatisfaction with the unit in the long run. I see many “Owner Installations” of new equipment or utilizing the "cheapest bidder" on a very limited budget that fall into this category.

The price of new equipment versus used is not nearly that much in comparison to installation cost.

Complete EFIS Systems

Today there are several new options with all-inclusive EFIS Systems that combine Engine Management with Flight Displays.

When choosing this type of system you are limited to the manufacturers functionality, probes and sensor systems.

Where should I install it?

I always try and get the Owner to install the engine monitor display in clear Pilot view, Primary scan. If you haven’t flown behind one of these units it is often difficult to imagine the utility of this additional equipment. I often tell Pilots that flying without an engine monitor is like going from a constant speed Prop to a fixed pitch Prop or retractable gear to fixed gear. It is very obvious that “something” is missing!

Quite often one has a legacy bar graph stand-alone unit on the Co-Pilot panel which they basically ignored over time. These units were 1st-2nd generation and were useful during that time period when utilized. However, these early designs were nowhere near as functional as the information presented in the current production units today. There used to be overlapped screens, switching channels or “step” buttons making these quite cumbersome to operate while flying the Aircraft.

Every individual manufacturer had their own “secret code” to unlock advanced features. Today most of these are an all-inclusive view on main screen. Direct Pilot view is of upmost importance to utilize the information displayed.

Don’t fall into the trap of “It will be less installation time if we just replace the legacy unit in the Co-Pilot Panel”. Out of sight, out of mind comes to mind when I see a modern display installed in the Co-Pilot Panel to cut back on installation cost. You will never be able to utilize the benefits of this equipment if it is out of view. The larger Primary Displays may be the exception to that rule, however, now we are seeing a trend to downsize these displays. I will discuss this further later on.

How long does it take to install an Engine Monitor?

A quality installation of a standard 6-Pt Engine monitor with Fuel Flow by an experienced installer should take between 2-3 days. Panel location, instrument relocation, options, etc. can vary these times. Two days is about standard for a Display and a basic EGT-CHT 6-point system. Some of the additional features can get a bit more complex and this adds time.

Note: These times vary from one manufacturer to the next. Some units have “non-standard” receptacles and attachments that are non-aviation, therefore, tooling and readily available supplies will not be standard. This may add to average installation times as well. The connectors and additional boxes utilized by some manufacturers also will add to installation cost as finding areas to accommodate such may take relocation of other equipment.

How much should I budget?

This varies with the type of unit, location and additional work included at time of installation.

Click on PHOTOS for the “Engine Monitor Installations” link showing various transducer and module installations. This will show a few “proper” techniques I have utilized over the years and some “not-so” favorable techniques in the “Unusual Findings” link I have found when opening an Engine compartment.

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