no idea, it just the way they did it- they were always fitted bipolar caps and later were fitted with polypropelene caps. I have worked on hundreds of the 9000 chassis and they have always been like that
they fail because they fail, just a common fault - thats why later models had the polypropelene caps fitted and they never fail. You should get a fair few years of operation with a standard bipolar cap so don't worry too much
they fail because they fail, just a common fault - thats why later models had the polypropelene caps fitted and they never fail. You should get a fair few years of operation with a standard bipolar cap so don't worry too much