Not only that, but a critical alignment is that the
Cam drive shaft must be absolutely in line with
the vertical centre line of the dynamo armature,
and that the dynamo bearings - especially the top
one, are in no way worn. If either are oyt then
there will me a "wobble" when rotating and the
resulting fatigue stresses will soon cause the
coupling to break - if not worse.
You will probably also need shimming spacers
to ensure that there is no bending in the coupling
due to vertical misalignment, and do this after also
ensuring that the two coupling yokes are exactly
parallel horizontally and correctly aligning
when they rotate
This seemingly simple fitting is in fact something
that needs graet care and not a little skill.
Whilst it's all apart, fit a modern oil seal to the
lower end of the cam drive housing if there's not
one there already, to stop the dynamo filling
with oil. Afterwards do not forget to oil the
dynamo bearings periodically ! <G>
Clive
Oxford UK
==========================
----- Original Message -----
From: "Hiro Nishio" <hiro@octagongarage.com>
To: "'Bill Tantau'" <bill707@earthlink.net>; "'Terry Sanders'"
<taterry@pacbell.net>; <mg-mmm@autox.team.net>; <DB35PA@aol.com>
Sent: Thursday, November 06, 2008 1:00 PM
Subject: RE: unusual occurance
> Hi Don,
>
> I have fixed such problems several times in the past.
> When you set up the cam bevel gear, the coupling must not be stretched nor
> pressed,
> otherwise it sometimes breaks.
> If you are not lucky enough, drive fork breaks.
>
> Good luck,
> Hiro
>
> -----Original Message-----
> From: owner-mg-mmm@autox.team.net [mailto:owner-mg-mmm@autox.team.net] On
> Behalf Of Bill Tantau
> Sent: Thursday, November 06, 2008 3:35 AM
> To: Terry Sanders; mg-mmm@autox.team.net; DB35PA@aol.com
> Subject: Re: unusual occurance
>
> Hi Don!
> Since we don't hear of this sort of failure very often ,if at all, I'd
> suspect
> some sort of installation anomaly - or - material failure. A close
> inspection
> of the bits should tell.
> Bill Tantau
>
> -----Original Message-----
>>From: Terry Sanders <taterry@pacbell.net>
>
>>Don, don't be discouraged. The factory file on my NA sez that the
>>coupling
>>broke in Banbury during its maiden voyage from the factory to the dealer
>>in
>>northern England!
>>They sent a mechanic to fix it....I have his report from Jan 1935.
>>Terry in Oakland
>>
>>--- On Wed, 11/5/08, DB35PA@aol.com <DB35PA@aol.com> wrote:
>>From: DB35PA@aol.com <DB35PA@aol.com>
>
>>Recently gave PA 1823 one of her longest runs to-date... about 80 miles.
>>When I fired her up Sat AM to go to local Monthly MG Club meeting, was
> greeted
>>
>>by a loud knock which rose and fell with RPM. BIG sinking feeling in
>>stomach!
>>
>>Later, we determined the knock to come from the top end and found the
>>flexible coupling on the vertical to have broken through one of the 4 bolt
>>holes.
>>
>>New part on the way from S&V but curious... has anyone else ever suffered
>>the same? Do I have something cranked down too hard? I have done a lot of
>>work
>>
>>in this area from the time it swallowed the brass distributor drive gear,
>>rebuilding dynamo after cutout stuck...and addressing oil leak down the
>>cam
>>drive.
>>
>>Thoughts about coupling failure? Just fatigue after 74 years?
>>Thanks
>>Don B.
>
> /// unsubscribe/change address requests to majordomo@autox.team.net or
> try
> /// http://www.team.net/cgi-bin/majorcool
> /// http://www.team.net/mailman/listinfo
> /// Archives at http://www.team.net/archive/mg-mmm
> /// Send list postings to mg-mmm@autox.team.net
>
> /// unsubscribe/change address requests to majordomo@autox.team.net or
> try
> /// http://www.team.net/cgi-bin/majorcool
> /// http://www.team.net/mailman/listinfo
> /// Archives at http://www.team.net/archive/mg-mmm
> /// Send list postings to mg-mmm@autox.team.net
/// unsubscribe/change address requests to majordomo@autox.team.net or try
/// http://www.team.net/mailman/listinfo
/// Archives at http://www.team.net/archive/mg-mmm
|