Some PMA holders are supplying you with only a lower cost Steel Ball Bearing for used in Goodrich Starter Generators where the CMM clearly MANDATES using a Ceramic Hybrid Ball Bearing. In more demanding Starter Generator applications, where steel ball bearings have not provided adequate service life and have been prone to repeated failures, the OEM has replaced the steel ball bearing 03-6009-23 with the ceramic hybrid 03-6009-25 and the 03-6010-18 with the ceramic hybrid 03-6010-19 through mandatory service bulletins and similar documentation. Like the OEM, Miraj supplies a Ceramic Hybrid PMA bearing for these more demanding applications - so why are other companies taking shortcuts and supplying a lesser product. As the leading PMA supplier of Starter Generator replacement parts, we cannot recommend or endorse this cost saving practice engaged in by some some competitors. If you have any doubt you are not being provided with a ceramic hybrid bearing ask the PMA holder to put it writing or contact Miraj for help in identifying these products.
Why are some PMA Holders supplying Steel Ball Bearings where the Goodrich CMM Calls for a Ceramic Hybrid?
A repair shop forwarded us a competitors set of FAA PMA starter generator bearings for further inspection and lab analysis. The subject bearing for Goodrich/APC starter generators are offered at a very AFFORDABLE price and the question that was asked was – How can these bearings that are the same size and somewhat similar in appearance be priced lower than the rest and, more importantly, are they of the same design and material quality as those offered by Miraj and other industry leaders? A summary of the inspection findings can be found below.
1. The PMA supplier of the AFFORDABLE bearing is actually utilizing a $7.00 Chinese Made Industrial Bearing available from almost any Indsutrialgrial/Agricultural bearing distributor. They actually tried to rub off the name of the manufacture from the seal itself - damaging the seal in the process. Why take the chance and install a $7.00 industrial bearing in your Starter Generator? We supply a precision US Made Abec 7 bearing for Starter Generator applications for a reason. Never settle for a lesser product to save a few dollars.
2. The subject industrial bearing utilizes only a low cost 250F degree rated Buna-N-rubber seal where the OEM and Miraj supply a bearing with Viton seals carrying a temperature rating of 550F. The PMA holder also utilized an industrial/consumer goods lubricant not used by any OEM or established industry aftermarket PMA holders. The use of an inferior seal and lubricant can lead to lubricant failure, overheat and premature bearing failure. Why take a chance with your customer's valuable equipment?
3. The PMA bearing utilized a ball piloted retainer/cage which is not the type preferred by the OEM's, Miraj and other industry leaders. This type of cage can lead to unacceptable levels of heat at high speeds, lubricant deterioration and premature failure.
A US PMA Holder Supplying Chinese made Industrial Bearings For Use In Starter Generators -
AFFORDABLE PMA's should never mean compromising on QUALITY!
PMA DESIGN, MANUFACTURE AND SALES