John, I'm with you. I try to make sure wheel bearings are made in an "old
school" country like Canada, US, Germany, Italy, England, Japan etc.
Although I don't have your experience in aircraft engines, I DO have plenty
of experience in motorcycle and aircooled engines, since the late 60's. I
steer clear of Chinese bearings as much as I can, as I've heard this all too
often. Interesting comment from a mechanic friend of mine from Mazda Canada;
"All our bearings are Japanese made, so we don't have warranty issues" I
don't know if that's true, but he is a master mechanic, and no fool. On the
other hand, I've got some EXCELLENT tools that are of Chinese/Taiwan
manufacture; their name is Craftsman !!!
Courtney

----- Original Message -----
From: "John Rodgers" <inua@CHARTER.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, July 30, 2009 8:52 AM
Subject: Wheel Bearing Problem Resolved

> Final Report
>
> After having new rotors and new bearings installed - and ending up with
> a loud whine right out of the chocks - the left front rotor was pulled
> and that new bearing was turned by hand. As it was turned it felt like
> sand was in the bearing. The bearing was cleaned and inspected closely.
> The rollers were pitted. . Not sure what caused this as I'm absolutely
> certain that bearing was immaculate when it was greased thoroughly with
> clean grease - and adequately greased as well. . I have greased hundreds
> of bearing of this type and know what I am doing. And - the bearings
> were definitely not over tightened  The only thing I could attribute
> this immediate failure to was some fault in the manufacturing process. I
> have never in all my career as aircraft mechanic - and part time Vanagon
> mechanic - encountered a wheel bearing failure almost right out of the
> box. This was the first time I have ever used a Chinese manufactured
> bearing, and can only attribute this failure to the manufacturing
> process. Though new, I replaced the bearings on both sides of the
> vehicle with new one's made in England. I hope they do not fail. Thus
> far they have worked fine with no further problem.
>
> As for the Chinese parts - could have been a fluke, the failure out of
> the box. I had that happen  with a $5000 aviation navigation unit once.
> But - I have jeweler/watchmaker friend who has told me that the Chinese
> made things  he sees in his trade reflect weaknesses in manufacturing
> processes - from measurements to alloying, hardening and surface
> treatments.
>
> Take it for what it's worth.
>
> John Rodgers
> 88 GL Driver