12 replies to this topic

[sh4ne]

Hi, hoping someone can point me in the right direction on this one.

 

1999 1.3 Mpi Mini Mayfair

When driving at a consistent speed the mini feels like it is going to shake itself apart!

I thought the suspension was the cause but now I am leaning towards the engine itself as the culprit?

 

The engine will idle perfectly well, no issues

On acceleration upto speed - say 50mph there are no issues, the pull is very strong.

Now, if I want to remain at 50mph, so at a consistent speed, the car starts to shake - it feels like a front to back shake and not a side to side. The steering wheel has a little bit of a judder but this does not match the overall shake.

 

I hope that makes sense, so on acceleration to any speed the mini feels great, the issue is if I want to remain at a constant speed (any speed) it will feel as though the car is going to shake itself apart!

 

If you need anymore info let me know :) 

 

I just need to know where to start looking.

[nicklouse]

wheels need looking at, balance, egged tyres, wheel nuts present and the trackrod ends and ball joints.

[nicklouse]

and then the radius arms for wear.

[sledgehammer]

as above , check tyre pressures , are side walls ok , has it been curbed recently ? 

 

I would swap front tyres to rear 

 

I have found nylon ply tyres go like this on hot days when you stop , they leave a flat spot which can cause vibration for a while after

 

& as above again - grease everything up that has a nipple (on the car)

[sh4ne]

Thanks for the super quick responses - OK will start with suspension parts.

I originally suspected this but with my ride out last night it seemed odd that its only noticeable when at a constant speed.

 

I guess all the suspension components are under pressure when accelerating so not so apparent?

 

I will investigate further and feedback... :)

[nicklouse]

no, look at the wheels first.

[absx2]

As nicklouse said, its almost certainly wheel related be it wheel balance,flat spots in the tyres, bent rims etc them follow with checking for blown shocks worn suspension parts and if the car is new to you check for badly cast discs and rear drums.

I had a badly balanced pair of front tyres fitted and it would make the bonnet shake from side to side at 50 MPH.

I also had a badly cast genuine Rover rear drum that effected the wheel balance at around 50 MPH it was a very low mileage one lady owner car that had clearly not been over 50 from new. having balanced the wheels several times and blaming the machine discovering the REAR drum finally solved the issue. Bit of a strange one that.

[psychobob]

if all else fails, it might be worth looking at your engine mounts and steady bushes? if its smooth under acceleration, but then shaking front to back, it could be the top steady? i'd deffo look at the wheels/suspension first though.

[ukcooper]

Jack each wheel up in turn on the Subframe, spin the wheel round fast as you can by hand and see if there's anything out of shape.

while each wheel is up , make sure there no wires or anything sticking out the rubber ( it will slice your hand open if thee is). and feel for any lumps bump.

Check wheel for wobble hand at 12 o'clock 6 o'clock, pull at 12 o'clock push at 6 o'clock and vice Vera see if there is any movement. Then same @ 1/4 past and quarter two..

Play with ya nuts.

Good working practice....MAKE SURE THE JACK IS SECURE WHEN YA WOBBLE THE WHEEL. preferable with the spare wheel under a solid point of the car so if it ever drop it drops on the wheel not on ya legs.

[Spider]

I recall not long ago a similar problem coming up with one of these. The Guy who owned it was a Mechanic (and a good one!) 35+ years experience and very good with Minis, but this had him stumped and took some time to narrow it down.

 

Listing what he did;-

    Balance Wheels (F & R)

    Check wheels for Bends and cracks

    New Tyres

    New Disc Rotors and then had them balanced

    New Wheel Bearings

    New Drive Flanges

    New CVs

    New Engine Mounts

    New Engine Steadies

    New Ball Joints

    Check Steering Arms for tightness

    New Subframe Mounts

    Flywheel Balanced (getting desperate now!)

    New Steering Rack - which appeared to cure it, buy was temporary, but gave more of a hint

    I think there were a handful of other things tried too

 

This was over a few months

 

Eventually, he swapped out I think it was the LH Hub for a borrowed used one and it was cured. Now we never did get to find out what it was with that Hub and why it did it.

 

I gotta admit, it really had me stumped and frankly, still does.

Edited by Moke Spider, 22 July 2016 - 07:52 PM.

[sledgehammer]

Eventually, he swapped out I think it was the LH Hub for a borrowed used one and it was cured. Now we never did get to find out what it was with that Hub and why it did it.

 

I gotta admit, it really had me stumped and frankly, still does.

 

my money is on bearing not seated correctly - in that case

 

will show under load - but maybe not when the wheel is unloaded ie on a jack

Edited by sledgehammer, 22 July 2016 - 08:07 PM.

[sh4ne]

Thanks for all the comments, I have loads to get on with.

Will start with the simplest - get the wheels checked and go from there...

 

Will post back with my progress and hopefully resolve :)

[tiger99]

Good abvice above. If all these checks do not find the cause, check your subframe mounts. Actually you should probably check them anyway. If they are the standard rubber type it is not unlikely that one or both of the toeboard mounts are broken.