Re: Bad vibrations

[Dave Biggs <D.Biggs@domain.elided>]

Dean Lewsam wrote:
> 
> Dear Stag Digest Members,
> I have just got my car back after being off the road for 6 months or so
> having a full engine rebuild. I must say it is great to be back on the road
> and all initial indications as to the work performed are positive!!
> 
> But back to an older problem......
> 
> When I first purchased my 76 Stag, I noticed it has quite a noticeable
> vibration (more seemingly from somewhere in the drive train) at speeds over
> 100km/h (not really noticeable from 0-80km/h). After some initial
> inspections we did most of the obvious things such as wheel balance (front
> and rear) and new tyres. This did not cure the problem. I then had the tail
> shaft out serviced and rebalanced. It was apparently "out" requiring some
> minor work before refitting. This however has not cured the problem. I
> replaced the fan which was missing half a blade (hell these things are
> expensive to replace!!) thinking this may be the cause. I have also had the
> rear axle splines replaced to correct a typical Triumph twitch. But still
> the vibration persists. I know that the steering linkages are not A1 and
> this is maybe the next step. I have also had the rear wheels checked that
> they are "in round" and they appear O.K. I would welcome any suggestions
> from members of the digest as to practical next steps to correct the
> problem. I was wondering if rear wheel alignment may have anything to do
> with causing a vibration such as this. Someone else also suggested that
> rear brake drums occasionally can go out of round (and hence cause
> vibrations) and if anyone has had any experience or knowledge of this I
> would be most interested.
> 
> Any suggestions, comments welcome !!

Dean,

A thought that crossed my mind is whether the rear shocks/springs are
past their best and allowing the rear suspension to oscillate up and
down just at certain speeds/frequencies.

Regards,

Dave.
-- 
	Dave Biggs                       
	Senior Design Engineer 	
	Fujitsu Telecommunications Europe Ltd, 
	Birmingham Business Park,Solihull Parkway, Birmingham, B37 7YU.
	mailto:D.Biggs@domain.elided  tel: 0121 717 6094  efax: 0121 717 6014