C-172 Centurion Diesel, Engine Installation Overview

Cessna 172 Centurion Diesel - Installation Overview and Details

This airplane is being converted and was about four days from being done when we saw it.

The prop is from an outfit that does racing props and is well known in that part of the business (although at this point, late Saturday night after many hours of baby duty, I can't come up with the name). It is wood with a fiberglass coating, titanium leading edges, and show-only boots.

Behind it is the reduction gearbox. Right now they're replacing these at 600 hours, but they've also put them in a military application where they've gone far longer.

Under the engine at the lower set of blue hoses is the oil cooler, which sits where the original engine air filter was. The cabin heat runs off this.

The big white scoop at the upper middle of the picture with the single blue hose is the radiator. The engine is liquid cooled and uses a 50/50 mix of water and the blue antifreeze that goes in Mercedes-Benz and BMW products.

Here's a better look at the radiator. It's aluminum, and given that I've been burned many times by aluminum radiators, intercoolers and the like I took a pretty good look at it. It's a very nice piece of engineering, and I think it will hold up very well.

All the intake air from the left side of the engine winds up here.

Just to the left of the scoop is the coolant reservoir.

They claim that you should never have to add coolant, and to date that's been the case on all the existing conversions.

The oil dipstick is just to the left of the coolant reservoir But, allegedly they don't use oil either..

Here's a little closer look. The coolant reservoir is about dead center. The long pipe on the left is the intake manifold tupe with several sensors. The oil dipstick is between the reservoir and the manifold.

Here's the view from the right side. The big tube in the foreground is the engine air. What's noteworthy in this picture (and in the rest as well) is the attention to detail. Nothing is left to chance. Even the lowly tie wraps are set at very precise locations and all are clocked the same way. There's absolutely nothing left swinging in the breeze.

This is the turbo installation, just left of center. Note the vacuum control. I asked about this-it's controlled by the FADEC, and they've not had trouble with them.

This is the exhaust system. I got told that it was quiet, and this is proof. One piece of inconel pipe, bent around to a 180 and coming out of the original hole. No muffler, nothing. One less thing to wear out.

An electric fuel pump is on the firewall where the gascolator used to be.

Here's the back of the engine. It uses a serpentine belt to run all the accessories. These belts typically go 150k miles or better in cars, and in this installation they get done at the engine replacement so they should not be an issue.

One thing I was impressed with, and it's not evident here, is that you can GET TO THIS. The belt and its tensioner are out in the open, and the alternator looks as though it would take ten minutes to change once the cowl is off.

To the right and below is how the engine arrives for installation, and this is the same package used when it's replacement time as well. Everything is supplied new, from the spinner to the engine mount and including all accessories. They claim the engine swap is a 12 hour job, and most of that is wiring the FADEC computers (which are new, too.).

This is the same package, looking at it from what would be the propeller end.

The large scoop on the right is the intake for the radiator, and the smaller intake on the left is the intercooler.

The entire installation is very clean and appears well thought-out. There were three of these engines on the floor the day we visited, and all three were uniform down to the location and orientation of tie wraps.

The packing was impressive too. The parts for each task are packed together, so you don't have 1000 small parts spread out across the floor at one time. The conversion is labor-intensive (150 man-hours or so) but each mechanic I spoke with had high praise for the whole package. One was on his first conversion, and said that he found the instructions (furnished as a PDF) well written and easy to follow.