Research Info: was: All bearings are not equal...

[hdavis]

>
>Henry has confirmed that the parts #s are the same not different like
>you say. I still say we got closer to the truth today. I am proud of
>that even if I was wrong.

So nobody gets confused - Arch is right the Timken order numbers are the
same. Tom is also right that there are additional numbers etched on the
spacer and races.

There lies the whole source of confusion. Timken says that they don't
"select" bearings. But the special ordering grooup does say that they will
match bearings. SO, what we have is a contraditction by Timken techies
about what they do (it really isn't a contradiction since they don't go
through all of the bearings to find matched sets - they do match them some
other way).

Arch found out that Timken says they don't select. Wes says he gets "the
cream of the crop" in an article. Maybe Wes' casual language is part of the
problem we've just uncovered.

I didn't notice the etched numbers until Tom pointed them out to me - I
just saw part numbers on the outside of the packing. I didn't notice the
numbers ont he bearings that were installed on the Palm Beach. But, sure
enough they're on the bearings going into my Royale.

I have to say that when Wes told me that they got special matched bearings
BUT Timken wouldn't assign a new part number I was first suspicious and
then cautious. I generally trust Wes' information, and understand that
Cinnabar has some legal considerations about modifications because they are
the GM licensee. My first concern was that I know how to determine a GMC
specified bearing from some off-the-shelf variety. Then I got interested in
the issues of bearing life - and that's how I discovered that Timken does
assemble special sets but doesn't change the basic part number.

Let's all remember that the questioning and search for facts that Arch and
others have done is part of what helps us keep the GMCs on the road. In 26
years the GMC has gathered a lot of myths - some good and some not so good.
I also appreciate Tom's strong reminders of why the Cinnabar bearings are
different and the engineering facts behind them.

I hope that this note keeps us from having any more confusion about the
Timken bearings - I'll post when I have more information.

Henry

Henry Davis Consulting, Inc / new product consulting
PO Box 1270 / product readiness reviews
Soquel, Ca 95073 / IP reviews
ph: (831) 462-5199 / full service marketing
fax: (831) 462-5198
http://www.henry-davis.com/ http://www.henry-davis.com

 

[thomas g. warner]

Henry one more fact worth noting. Cinnabar is not the only source for these
bearings, contrary to what Wes says. I checked several other sources and
found that Gateway also sells the special matched Timken bearing sets, and I
bought mine from there for $77 a set includeing the inner and outer seals.
As it turned out that was the price for just the regular bearing at my local
supplier. They are etched with the proper clearances. Note in one of your
previous e-mails that you noted that Timken had told you there were other
"customers" for the special bearings.

As Arch says "we are learning"

>
>>
>>Henry has confirmed that the parts #s are the same not different like
>>you say. I still say we got closer to the truth today. I am proud of
>>that even if I was wrong.
>
>So nobody gets confused - Arch is right the Timken order numbers are the
>same. Tom is also right that there are additional numbers etched on the
>spacer and races.
>
>There lies the whole source of confusion. Timken says that they don't
>"select" bearings. But the special ordering grooup does say that they will
>match bearings. SO, what we have is a contraditction by Timken techies
>about what they do (it really isn't a contradiction since they don't go
>through all of the bearings to find matched sets - they do match them some
>other way).
>
>Arch found out that Timken says they don't select. Wes says he gets "the
>cream of the crop" in an article. Maybe Wes' casual language is part of the
>problem we've just uncovered.
>
>I didn't notice the etched numbers until Tom pointed them out to me - I
>just saw part numbers on the outside of the packing. I didn't notice the
>numbers ont he bearings that were installed on the Palm Beach. But, sure
>enough they're on the bearings going into my Royale.
>
>I have to say that when Wes told me that they got special matched bearings
>BUT Timken wouldn't assign a new part number I was first suspicious and
>then cautious. I generally trust Wes' information, and understand that
>Cinnabar has some legal considerations about modifications because they are
>the GM licensee. My first concern was that I know how to determine a GMC
>specified bearing from some off-the-shelf variety. Then I got interested in
>the issues of bearing life - and that's how I discovered that Timken does
>assemble special sets but doesn't change the basic part number.
>
>Let's all remember that the questioning and search for facts that Arch and
>others have done is part of what helps us keep the GMCs on the road. In 26
>years the GMC has gathered a lot of myths - some good and some not so good.
>I also appreciate Tom's strong reminders of why the Cinnabar bearings are
>different and the engineering facts behind them.
>
>I hope that this note keeps us from having any more confusion about the
>Timken bearings - I'll post when I have more information.
>
>Henry
>
>Henry Davis Consulting, Inc / new product consulting
>PO Box 1270 / product readiness reviews
>Soquel, Ca 95073 / IP reviews
>ph: (831) 462-5199 / full service marketing
>fax: (831) 462-5198
>http://www.henry-davis.com/ http://www.henry-davis.com
>
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
"The beautiful Mohawk Vally"

 

[bdub]

A great idea John! And one that has recieved a little traffic here before.
I think our 'Gadget Guru' is working on a solution like this to add to his
AV-10 systems monitor. Isn't this correct Heinz?

>When the assembled axial clearance gets below minimum (0.002) it gets hot
>which makes the clearance even less (is that right?). So the temp
>signature looks like:
>
> *
> *
> *
> *
>****
>
>
>
>Whereas a bearing with greater than 0.003 probably looks like:
>
> * * *
> *
> *
>****
>
>
>Instead of taking the bearings apart to check them could we just
>monitor the temp signature? Are all failures preceded by this kind of
>heat signature?
>
>--
>"I do whatever my Rice Krispies tell me to..." John said, from inside a
>1974 Glacier.
>
>

 

[heinz wittenbecher]

>A great idea John! And one that has recieved a little traffic here before.
> I think our 'Gadget Guru' is working on a solution like this to add to his
>AV-10 systems monitor. Isn't this correct Heinz?

Have to find some sensors first
However, I do have a gadget that measures temperature accurately by simply
pointing it at the surface to be measured.

I plan to devise a manual recording scheme for now, i.e. once or twice a day
right after pulling into a rest area so that there is minimum natural
cooldown and by following the same sequence each time it may give me the
forwarn I'm looking for.

Of course that's all theory for now

It would stand to reason that a bad bearing would be hotter and retain that
heat long enough to measure.

Heinz

>
>

>>When the assembled axial clearance gets below minimum (0.002) it gets hot
>>which makes the clearance even less (is that right?). So the temp
>>signature looks like:
>>
>> *
>> *
>> *
>> *
>>****
>>
>>
>>
>>Whereas a bearing with greater than 0.003 probably looks like:
>>
>> * * *
>> *
>> *
>>****
>>
>>
>>Instead of taking the bearings apart to check them could we just
>>monitor the temp signature? Are all failures preceded by this kind of
>>heat signature?
>>
>>--
>>"I do whatever my Rice Krispies tell me to..." John said, from inside a
>>1974 Glacier.
>>
>>
>
>

 

[john dolan]

This whole thing is quite a bit clearer and more factual now. I think
some credit should be given to the guy with enough guts to raise the
question (this time) and really define the perimeter of the subject
matter. A good question take some reasearch and knowledge too...

> GMCers Don't take this the wrong way, I'm not trying to start
> something...this time I'm looking at a build up of almost 200
> messages and I can't be sure of who said what, but someone said
> they may have the same number or look the same. >>>

> My question is: How do we know this to be fact ? If Timken has
> ABC printed on a bearing, who do we know at Timpken that has
> told us that Cinnibar gets good ones and Mikey's Bearing Shop
> gets an inferior bearing. Don't throw things, guys, just askin' .

> MikeBeaton
> NS

I even learned something this time (and moved a message from my Out box
to my Hold box) and I am glad I did, because we also learned that
Off-Net-Communication (Henry's) can help in a situation like this. I
think we came to a firm conclusion punctuated by Arch saying ~ OK you
guys proved it, and for that, I give him a lot of credit. (and it
underlines the fact that the best bearing set for us is a set that has
been matched with the proper spacer so that the assembled axial clearance
is not too tight... not less than 0.0095). And thanks to Tom for being
persistant, otherwise this would still be in limbo with more folks buying
the cheapest timkens they could find, where numbers on the bearings
matched.

There is just one thing haunting me about this, I've re-read the article
twice and I can not find the part where Wes says he gets the cream of the
crop from Timkin. I know defending Wes seems to fall to me (and I don't
even know or particularly like the guy). Would somebody enlighten us on
this?

- --
I do whatever my Rice Krispies tell me to..." John said, from inside a
1974 Glacier.

 

[john dolan]

That should be "not less than 0.0095 unassembled axial clearance"...
- --
"I do whatever my Rice Krispies tell me to..." John said, from inside a
1974 Glacier.

 

[john dolan]

When the assembled axial clearance gets below minimum (0.002) it gets hot
which makes the clearance even less (is that right?). So the temp
signature looks like:

*
*
*
*
****

Whereas a bearing with greater than 0.003 probably looks like:

* * *
*
*
****

Instead of taking the bearings apart to check them could we just
monitor the temp signature? Are all failures preceded by this kind of
heat signature?

- --
"I do whatever my Rice Krispies tell me to..." John said, from inside a
1974 Glacier.