IFB INFORMATION

IFB = Integral Front Bearing : Also commonly known as a 5th Bearing. A bearing mounted on the propeller end of a Corvair conversion engine to help support and absorb loads on the engine caused by the propeller.

Our Design = The reason our 5th bearing is called an integral front bearing is because we have integrated the propeller hub into the existing Corvair crankshaft. This procedure resolves many issues and simplifies the engine. Here are the Pros....

1. The Crankshaft becomes a one piece unit. Once the propeller hub is installed onto the crankshaft it is treated as one unit. This includes grinding, nitriding, polishing and installation. This eliminates the need for safety shafts and hub bolts. As a consequence it is a lighter assembly.

2. The thrust flange that carries propeller thrust loads is now located at the front of the engine, not at the rear. It is also larger is size.

3. The main bearing and seal are locally available at auto parts stores for replacement purposes and come in a variety of sizes.

4. The robust front housing is able to carry a very high load compared to any other 5th bearing design currently on the market. We will be able to use constant speed propellers on this design.

5. This design also allows us to extend the propeller forward slightly to allow lower cooling and cowling drag.

6. Because of its simplicity its cost is very reasonable and actually less than others on the market.

CONS....

1. Has to be initially assembled in-house. Because of the nature of the front housing, it needs to be align bored to the case in-house. Afterwards, the case can always be dissassembled and bearings changed without disturbing the alignment. It is a simple and low cost procedure. We typically have shortblocks ready to go.

2. This may be a negative to those who have front starter setups. The IFB will only work with our rear alternator and starter setup. However, this allows the use of a 32 amp alternator and a started setup that is easy to maintain due to off the shelf starter and ring gear. That is a PRO!

PICTURES OF IFB ASSEMBLY:

Crankshaft with CNC'd Hub installed and reground

Case with housing attached and crankshaft

Crankshaft and Camshaft installed into case half

A finished short-block all torqued and ready to ship

Noteworthy: The prototype of this 5th bearing design we made is still flying today. It first saw service in 2007 and has hundreds of hours on that airframe. Since then there have been several aircraft in service that are flying with the IFB Conversion with no failures to date. Because of its design it can be maintained on the filed with no need to return to Azalea Aviation. Due to its simplicity and cost effectiveness we decided some time ago that all our engines will come equipped with the IFB.

Picture of Our Spyder 100 HP IFB Corvair Conversion Engine installed on a Zenith 750 display. The IFB allows the use of our cooling plenums and makes a clean, simple installation possible.

This design has been Patent Pending. For more information about our IFB products or products in general please contact us directly at Azalea Aviation.