Avglas STC, FAA-PMA repair kits for approved Continetal carburetor heat boxes are now manufactured by McFarlane Aviation. The Teledyne/Continental carburetor heat boxes are made from brazed steel and are used on many of the older light aircraft.
McFarlane’s elastomer bearing is assembled with tension between the mating surfaces. This tension prevents micro-movement and its related metal erosion. The bearing contact area that transfers vibration motion from the heat box to the butterfly shaft is hundreds of times greater than that of the original needle bearing.