fot
[Top] [All Lists]

Re: [Fot] Differential Pre-load

To: Bob Kramer <rkramer56@gmail.com>
Subject: Re: [Fot] Differential Pre-load
From: "van.mulders.marcel--- via Fot" <fot@autox.team.net>
Date: Thu, 30 Jan 2020 13:50:40 +0100 (CET)
Cc: fot <fot@autox.team.net>
Delivered-to: mharc@autox.team.net
Delivered-to: fot@autox.team.net
References: <1883458790.6650892.1580378894276.JavaMail.zimbra@telenet.be> <ED053B9D-3B4A-4441-8A5D-A5DAC07EC58F@gmail.com>
Thread-index: vrg+HYIaTUIGAOPlNya5izC8nbi8eg==
Thread-topic: Differential Pre-load
--===============5437462671665531774==
        boundary="=_9c4593a5-0c1a-4c29-8e4f-d8c61f9ef32d"

--=_9c4593a5-0c1a-4c29-8e4f-d8c61f9ef32d
Content-Transfer-Encoding: quoted-printable

Hallo Bob, the stub axle and bearings were discoloured by the heat and the =
stub axle was literally broken off, I don't remember anymore where. I suppo=
se the inside threaded part was broken off.=20
The inspector at the MOT obviously didn't know that these wheel bearings sh=
ould have some free play, contrary to modern cars. My friend felt unsure ab=
out it and he didn't argue with the MOT inspector. He also did not undo the=
 tightening when he had left the MOT station=20
Marcel.=20


Van: "Bob Kramer" <rkramer56@gmail.com>=20
Aan: "van mulders marcel" <van.mulders.marcel@telenet.be>=20
Cc: "TeriAnn J. Wakeman" <tjwakeman@gmail.com>, "fot" <fot@autox.team.net>=
=20
Verzonden: Donderdag 30 januari 2020 12:59:14=20
Onderwerp: Re: [Fot] Differential Pre-load=20

Only a post mortem on the parts could tell for sure, but it is fun to specu=
late. If we take the inspector at his word and the wheel bearing was =E2=80=
=9Cloose=E2=80=9D, the question of why that condition existed should have b=
een answered before tightening down the hub. Either bearing could have alre=
ady sustained damage from misalignment and bringing damaged and scarred rol=
lers back to spec could quickly result in overheating and terminal failure.=
=20
That would not be fun.=20

Sent from my iPhone=20



On Jan 30, 2020, at 4:08 AM, van.mulders.marcel--- via Fot <fot@autox.team.=
net> wrote:=20





BQ_BEGIN


TeriAnn,=20
Some years ago, a friend of mine took his freshly restored TR4 to the MOT. =
There he was told he had to adjust the front wheel bearings. He tightened t=
hese there and then to pass the MOT and on the way home a stub axle broke o=
ff because the bearing had seized, luckily without too much damage : beside=
s the stub axle and brake caliper bracket, a wing had to be repaired.=20
Marcel=20

Van: "fot" <fot@autox.team.net>=20
Aan: "fot" <fot@autox.team.net>=20
Verzonden: Donderdag 30 januari 2020 10:16:08=20
Onderwerp: Re: [Fot] Differential Pre-load=20

On 1/30/20 2:11 AM, van.mulders.marcel--- via Fot wrote:=20

BQ_BEGIN

Barry, if that is true about the rollers/races, how do you explain the pres=
cripion about the front wheel bearings : you need to back off the stub axle=
 nut to get some play for the bearings?=20
Marcel=20

BQ_END
Likewise with Series Land Rover wheel bearings. Leave them tight and they q=
uickly die.=20
TeriAnn=20

BQ_BEGIN



Van: "fot" [ mailto:fot@autox.team.net | <fot@autox.team.net> ]=20
Aan: "fubog1" [ mailto:fubog1@aol.com | <fubog1@aol.com> ] , "Bob Kramer" [=
 mailto:rkramer56@gmail.com | <rkramer56@gmail.com> ]=20
Cc: "fot" [ mailto:fot@autox.team.net | <fot@autox.team.net> ]=20
Verzonden: Woensdag 29 januari 2020 19:02:55=20
Onderwerp: Re: [Fot] Differential Pre-load=20

Preload is more for the life of the bearings than the gears. You preload a =
bearing to take up manufacturing tolerances and account for the anticipated=
 (by the manufacturer of the bearings) wear during their life time. There d=
oes need to be some 'squeeze" between the bearing races and the rollers or =
the rollers will not roll in lubrication. If any of you have ever rebuilt t=
he rear outer suspension on old XKEs, the tapers roller bearing in the oute=
r wishbone pivots wear out because the wishbone only moves up and down a fe=
w degrees. The tapered roller bearings never fully rotate and cause the rol=
lers and race to pit. Roller bearing must roll 360 degrees around to surviv=
e. Preload makes them do that.=20

Barry=20

On Wednesday, January 29, 2020, 09:41:34 AM EST, Bob Kramer via Fot [ mailt=
o:fot@autox.team.net | <fot@autox.team.net> ] wrote:=20


I think the main reason a specified amount of preload is required is that i=
t sets it up so that the bearings roll under mild tension. To tight and the=
 components slide over each other. Too loose and they cock in place. Withou=
t rolling, bearings will soon fail the same way a lifter that doesn't spin =
fails.=20

Bob Kramer=20


BQ_END


_______________________________________________=20
fot@autox.team.net=20

http://www.fot-racing.com=20

Archive: http://autox.team.net/archive http://www.team.net/pipermail/fot=20
arcel@telenet.be=20
_______________________________________________=20
fot@autox.team.net=20

http://www.fot-racing.com=20

Archive: http://autox.team.net/archive http://www.team.net/pipermail/fot=20
il.com=20

BQ_END



--=_9c4593a5-0c1a-4c29-8e4f-d8c61f9ef32d
Content-Transfer-Encoding: quoted-printable

<html><body><div style=3D"font-family: Verdana, Arial, Helvetica, sans-seri=
f; font-size: 10pt; color: #000000"><div>Hallo Bob, the stub axle and beari=
ngs were discoloured by the heat and the stub axle was literally broken off=
, I don't remember anymore where. I suppose the inside threaded part was br=
oken off.</div><div>The inspector at the MOT obviously didn't know that the=
se wheel bearings should have some free play, contrary to modern cars. My f=
riend felt unsure about it and&nbsp; he didn't&nbsp; argue with the MOT ins=
pector. He also did not undo the tightening when he had left the MOT statio=
n</div><div>Marcel.</div><div><br></div><hr id=3D"zwchr" data-marker=3D"__D=
IVIDER__"><div data-marker=3D"__HEADERS__"><b>Van: </b>"Bob Kramer" &lt;rkr=
amer56@gmail.com&gt;<br><b>Aan: </b>"van mulders marcel" &lt;van.mulders.ma=
rcel@telenet.be&gt;<br><b>Cc: </b>"TeriAnn J. Wakeman" &lt;tjwakeman@gmail.=
com&gt;, "fot" &lt;fot@autox.team.net&gt;<br><b>Verzonden: </b>Donderdag 30=
 januari 2020 12:59:14<br><b>Onderwerp: </b>Re: [Fot] Differential Pre-load=
<br></div><div><br></div><div data-marker=3D"__QUOTED_TEXT__">Only a post m=
ortem on the parts could tell for sure, but it is fun to speculate. If we t=
ake the inspector at his word and the wheel bearing was =E2=80=9Cloose=E2=
=80=9D, the question of why that condition existed should have been answere=
d before tightening down the hub. Either bearing could have already sustain=
ed damage from misalignment and bringing damaged and scarred rollers back t=
o spec could quickly result in overheating and terminal failure.&nbsp;<br><=
div>That would not be fun.<br><br><div dir=3D"ltr">Sent from my iPhone</div=
><div dir=3D"ltr"><br><blockquote>On Jan 30, 2020, at 4:08 AM, van.mulders.=
marcel--- via Fot &lt;fot@autox.team.net&gt; wrote:<br><br></blockquote></d=
iv><blockquote><div dir=3D"ltr"><div style=3D"font-family:'verdana' , 'aria=
l' , 'helvetica' , sans-serif;font-size:10pt;color:#000000"><br><div>TeriAn=
n,</div><div>Some years ago, a friend of mine took his freshly restored TR4=
 to the MOT. There he was told he had to adjust the front wheel bearings. H=
e tightened these there and then to pass the MOT and on the way home a stub=
 axle broke off because the bearing had seized, luckily without too much da=
mage : besides the&nbsp; stub axle and brake caliper bracket,&nbsp; a wing =
had to be repaired.</div><div>Marcel</div><hr id=3D"zwchr"><div><b>Van: </b=
>"fot" &lt;fot@autox.team.net&gt;<br><b>Aan: </b>"fot" &lt;fot@autox.team.n=
et&gt;<br><b>Verzonden: </b>Donderdag 30 januari 2020 10:16:08<br><b>Onderw=
erp: </b>Re: [Fot] Differential Pre-load<br></div><br><div><div class=3D"mo=
z-cite-prefix">On 1/30/20 2:11 AM,
      van.mulders.marcel--- via Fot wrote:<br>
    </div>
    <blockquote>
     =20
      <div style=3D"font-family:'verdana' , 'arial' , 'helvetica' , sans-se=
rif;font-size:10pt;color:#000000">
        <div>Barry, if that is true about the rollers/races, how do you
          explain the prescripion about the front wheel bearings : you
          need to back off the stub axle nut to get some play for the
          bearings?</div>
        <div>Marcel</div>
      </div>
    </blockquote>
    Likewise with Series Land Rover wheel bearings. Leave them tight and
    they quickly die.<br>
    TeriAnn<br>
    <blockquote>
      <div style=3D"font-family:'verdana' , 'arial' , 'helvetica' , sans-se=
rif;font-size:10pt;color:#000000">
        <div><br>
        </div>
        <hr id=3D"zwchr">
        <div><b>Van: </b>"fot"
          <a href=3D"mailto:fot@autox.team.net"; rel=3D"nofollow noopener no=
referrer nofollow noopener noreferrer" target=3D"_blank">&lt;fot@autox.team=
.net&gt;</a><br>
          <b>Aan: </b>"fubog1" <a href=3D"mailto:fubog1@aol.com"; rel=3D"nof=
ollow noopener noreferrer nofollow noopener noreferrer" target=3D"_blank">&=
lt;fubog1@aol.com&gt;</a>, "Bob Kramer"
          <a href=3D"mailto:rkramer56@gmail.com"; rel=3D"nofollow noopener n=
oreferrer nofollow noopener noreferrer" target=3D"_blank">&lt;rkramer56@gma=
il.com&gt;</a><br>
          <b>Cc: </b>"fot" <a href=3D"mailto:fot@autox.team.net"; rel=3D"nof=
ollow noopener noreferrer nofollow noopener noreferrer" target=3D"_blank">&=
lt;fot@autox.team.net&gt;</a><br>
          <b>Verzonden: </b>Woensdag 29 januari 2020 19:02:55<br>
          <b>Onderwerp: </b>Re: [Fot] Differential Pre-load<br>
        </div>
        <div><br>
        </div>
        <div>
          <div class=3D"ydpcdfacf56yahoo-style-wrap" style=3D"font-family:'=
helvetica neue' , 'helvetica' , 'arial' , sans-serif;font-size:13px">
            <div dir=3D"ltr">Preload is more for the life of the bearings
              than the gears. You preload a bearing to take up
              manufacturing tolerances and account for the anticipated
              (by the manufacturer of the bearings) wear during their
              life time. There does need to be some 'squeeze" between
              the bearing races and the rollers or the rollers will not
              roll in lubrication. If any of you have ever rebuilt the
              rear outer suspension on old XKEs, the tapers roller
              bearing in the outer wishbone pivots wear out because the
              wishbone only moves up and down a few degrees. The tapered
              roller bearings never fully rotate and cause the rollers
              and race to pit. Roller bearing must roll 360 degrees
              around to survive. Preload makes them do that.</div>
            <div dir=3D"ltr"><br>
            </div>
            <div dir=3D"ltr">Barry</div>
            <br>
          </div>
          <div id=3D"ydpf5f47a82yahoo_quoted_0792558679" class=3D"ydpf5f47a=
82yahoo_quoted">
            <div style=3D"font-family:'helvetica neue' , 'helvetica' , 'ari=
al' , sans-serif;font-size:13px;color:#26282a">
              <div> On Wednesday, January 29, 2020, 09:41:34 AM EST, Bob
                Kramer via Fot <a href=3D"mailto:fot@autox.team.net"; rel=3D=
"nofollow noopener noreferrer nofollow noopener noreferrer" target=3D"_blan=
k">&lt;fot@autox.team.net&gt;</a> wrote: </div>
              <br>
              <br>
              <div>
                <div id=3D"ydpf5f47a82yiv1894590979">
                  <div>
                    <div dir=3D"ltr">I think the main reason a specified
                      amount of&nbsp; preload is required is that it sets i=
t
                      up so that the bearings roll under mild tension.
                      To tight and the components slide over each
                      other.&nbsp; Too loose and they cock in place. Withou=
t
                      rolling, bearings will soon fail the same way a
                      lifter that doesn't spin fails.
                      <div><br clear=3D"all">
                        <div>
                          <div class=3D"ydpf5f47a82yiv1894590979gmail_signa=
ture" dir=3D"ltr">
                            <div dir=3D"ltr">Bob Kramer</div>
                          </div>
                        </div>
                        <br clear=3D"none">
                      </div>
                    </div>
                  </div>
                </div>
              </div>
            </div>
          </div>
        </div>
      </div>
    </blockquote>
    <br>
 =20
<br>_______________________________________________<br>fot@autox.team.net<b=
r><br>http://www.fot-racing.com<br><br>Donate: http://www.team.net/donate.h=
tml<br>Archive: http://autox.team.net/archive http://www.team.net/pipermail=
/fot<br>Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/van.m=
ulders.marcel@telenet.be<br></div></div>___________________________________=
____________<br>fot@autox.team.net<br><br>http://www.fot-racing.com<br><br>=
rchive http://www.team.net/pipermail/fot<br>Unsubscribe/Manage: http://auto=
x.team.net/mailman/options/fot/rkramer56@gmail.com</div></blockquote></div>=
<br></div></div></body></html>
--=_9c4593a5-0c1a-4c29-8e4f-d8c61f9ef32d--

--===============5437462671665531774==
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________
fot@autox.team.net

http://www.fot-racing.com

Archive: http://autox.team.net/archive http://www.team.net/pipermail/fot



--===============5437462671665531774==--

<Prev in Thread] Current Thread [Next in Thread>