An odd Job at work

[tomsutton529]

We got a call the other day from an elderly gentleman in the north west area wanting to buy a bit of kit for vibration analysis, once we told him the price he asked about a day rate for us to come and have a look at the job..

The job in a pre world war Rolls Royce that is vibrating when the car get to 40Mph..

I am fully capable at having a go at looking for a resonance issue with the body, unbalance in either a drive shaft or crank shaft...

Just wondering if its someone on here or they know this person.. I am not trying to follow up on a job, it just sounds damn interesting.

 

[gordon stephenson]

Unbalance in Tyre,Wheel wobble, propshaft etc,, I had a mates car to look at for vibration years ago, one of the fan blades had been shed, he was over the moon with such an easy fix,

 

[gaz1]

vibration through steering wheel is also unbalance of tires another an egg in the tire wall can also cause vibration ive seen it both in the front tyres and also in the back tyres

 

[the snooper]

i would be looking at propshaft and wheels, engine and gearbox mounts, forget anything engine related as it would still do it whilst stationary

 

[Kent]

Drive it under 40 then?

 

[MrFluffy]

Maybe send malcom a pm to nudge him, he dabbled or worked professionally as a vehicle NVH analysis engineer and was posting a few years back about comissioning a old NVH analysis computer. Malcolm as in the main man btw!

 

[Tigman]

Take it out for a good test , pick up the misses and the family and have a jolly !

 

[tomsutton529]

Cheers guys.

 

[jordan1]

Sounds like UJ joints.

 

[tomsutton529]

It sounds like it could be anything to be honest. He sounds like a clued up chap, I am more than capable of taking the correct readings, in the right places and doing the right analysis as that is my job and I have a few years experience of working on cars, if anything needs balancing we have the kit in the workshop to get it done.. from what ive been told about the job it sounds more like a resonance issue, but its what is causing the resonance is the issue. it could be something as simple as very low level unbalance in a driveshaft that at 40MPH matches the resonate frequency of some part of the body he has over engineered, by that I mean by some freak of physics he has added more strength to an area that has altered the natural frequency of that area and brought it closer to the frequency of the unbalance...

 

[octo0072000]

i had a problem with old cross ply tyres on a landrover called setting
starting from cold felt like wheels out of balance/round but no, jack it up cold spin wheel tyre out of round all four drive for about 5 miles no problems all round again
something to do with the tyre carcase setting/settleing
changed tyres never another problem

 

[tomsutton529]

i had a problem with old cross ply tyres on a landrover called setting
starting from cold felt like wheels out of balance but no, jack it up cold spin wheel tyre out of round all four drive for about 5 miles no problems all round again
something to do with the tyre carcase setting
changed tyres never another problem

That's interesting.

 

[octo0072000]

That's interesting.

the answer came from goodyear tyre rep odd to drive then ok after 5 or more miles this was summer so no idea what winter would have been like