Rick - exactly, except you missed out the crucial bit. The manual says to
put too many shims in to create too much endfloat, tighten the nut, measure
the end-float, then reduce the shims "to get the correct the end-float".
I.e. you end up with end-float. You cannot have end-float *and* pre-load.
Some applications may well call for pre-load. The MGB requires .002 to .004
end-float.
PaulH.
http://freespace.virgin.net/paul.hunt1/
-----Original Message-----
From: REwald9535@aol.com <REwald9535@aol.com>
To: paul.hunt1@virgin.net <paul.hunt1@virgin.net>; mgs@autox.team.net
<mgs@autox.team.net>
Date: 31 March 1999 04:16
Subject: Re: pulling out the spacers in the front hubs
>Paul,
>If you tighten the nut on the end of the axle to 70 Ft. Lbs. I can tell
you
>for certain there will be no endfloat. (unless you have superman doing the
>checking)
>so where does the end float referred to in the manual come from and why
>doesn't the wheel lock up when torqued this tight?
>If you have a wheel bearing laying around pick it up and look at it. If
you
>hold the inner race stationary you will notice a small amount play in the
>axial direction in the outer part of the bearing (caused by clearances in
the
>cage). Now go wipe all that grease off you hands.
>When an MG front hub is assembled it goes something like this. The inner
>bearing is against the shoulder on the axle stub then comes the spacer,
then
>shim(s) then the outer bearing, washer then the nut. When torqued down the
>nut presses against the washer which presses against the outer bearing
which
>presses I sure you get the idea. As I said at the beginning of this post
when
>torqued to 70 Ft. Lbs. there will be NO endfloat in THIS part of the
assembly.
>The endfloat comes from the play inside each bearing. By adjusting the
amount
>(thickness) of shims in the pack you can adjust the amount of endfloat and
the
>amount of preload on the bearings. Look at the procedure in the manual, it
>tells you to put too many shims in to create excessive endfloat, measure
the
>endfloat and adjust the pack accordingly. If you were to take out too many
>shims the endfloat would be non extant and the preload excessive causing
>premature bearing failure. If the endplay is excessive the preload will be
>low causing vibration in the brakes, and once premature bearing failure.
In
>this case adjusting endfloat provides a way to preload the bearings
correctly,
>kinda neat actually. As once set up correctly as long as no parts are
>replaced (or lost) any idiot can repack the wheel bearings and get it
right.
>I hope that this clears up any confusion.
>Rick Ewald
>
>
>In a message dated 3/30/99 10:58:18 AM Pacific Standard Time,
>paul.hunt1@virgin.net writes:
>
>> The Leyland Workshop Manaul and Haynes are quite clear in respect of the
>> MGB, there should be an end-float of .002 to .004, not a preload.
>>
>> PaulH.
>> http://freespace.virgin.net/paul.hunt1/
>>
>> -----Original Message-----
>> From: REwald9535@aol.com <REwald9535@aol.com>
>> To: paul.hunt1@virgin.net <paul.hunt1@virgin.net>; mgs@autox.team.net
>> <mgs@autox.team.net>
>> Date: 30 March 1999 07:24
>> Subject: Re: pulling out the spacers in the front hubs
>>
>>
>> >Paul,
>> >Conical bearings need some (not much) pre loading. There are several
ways
>> to
>> >do this. MG used a spacer and as you mentioned a torque of 40-70 Ft
Lbs.
>> >With the spacer and correct shims fitted this gives the correct pre
load
>on
>> >the wheel bearings. Other makes have a different way of skinning the
same
>> >cat. My company (Volvo) on 240's have the technician torque the wheel
>> >bearings to 30 Ft. Lbs. and spin the wheel to center the bearings, then
>> loosen
>> >the nut 1/2 turn and retorque to 11-15 inch Lbs. this also pre loads
the
>> >bearings to the correct amount. Either way the idea is to remove the
slop
>> and
>> >not to over load the bearings which would cause a premature failure.
>> >Rick Ewald
>> >67 MGB
>> >
>> >In a message dated 3/29/99 12:30:42 PM Pacific Standard Time,
>> >paul.hunt1@virgin.net writes:
>> >
>> >> As well as the spacer and shims, when tightened to the correct torque
of
>> >> 40 - 70lb ft, strengthening the axle shaft they also stop any
tendency
>> for
>> >> the inner races to spin on the axle. The correct shims will give an
>> >> end-float of .002 to .004in, not a loading of 11 to 15 in lb.
>> >>
>> >> PaulH.
>> >> http://freespace.virgin.net/paul.hunt1/
>> >>
>> >> -----Original Message-----
>> >> From: Karl Shultz <karl.shultz@ibm.net>
>> >> To: MG List <mgs@autox.team.net>
>> >> Date: 26 March 1999 05:20
>> >> Subject: pulling out the spacers in the front hubs
>> >>
>> >>
>> >> >Hello MGers,
>> >> >
>> >> >Hope all is well with you getting your assorted brit cars ready for
>the
>> >> >warm season. I'm coming along myself - I've replaced the brake
lines
>> >> >(which looked as old, if not older, than the entire 73 B itself),
the
>> >> >heater control valve (with a gasket now) some hoses, and made some
>> hacks
>> >> >into the electrical system whose effectiveness seems to vary day to
>> day.
>> >> >
>> >> >Anyhow, I took a trip to Flying Circuis Cars in Durham, NC.
They're a
>> >> >Brit car specialist where I buy my parts. So I go to buy shims for
>the
>> >> >front hubs (which rattled about horribly) and a guy came in from
the
>> >> >garage area telling me something interesting. I'd like to bounce
this
>> >> >off the group, it seems odd.
>> >> >
>> >> >He said that the big spacer, and the accompanying shims, could be
>> >> >installed in the trash can rather than the hub. "Conical bearings
can
>> >> >accept the load themselves no problem; people used to think you had
to
>> >> >make perfect contact between the bearing housings with those shims,
>but
>> >> >all the cars we work on, we just pull all that stuff out.
>> >> >
>> >> >Odd, no? I tried it. The hub can be put together and adjusted up
>just
>> >> >fine without all this stuff. But concerned for the longevity of
the
>> >> >bearings (they say "made in england," so they must be as old as the
>car
>> >> >too...) I haven't really finalized the work.
>> >> >
>> >> >Any thoughts on this odd suggestion?
>> >> >
>> >> >--
>> >> >Karl Shultz
>> >> >95 Integra GS-R, black, loud
>> >> >73 MGB, orange, only marginally drivable
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