"Twitchy" rear end

Post by **paulhumphries** » Mon Feb 05, 2007 4:55 pm

I notice on powering out of a roundabout sometime there seem to be what I can only describe as rear wheel steer.
It's the only part of my Minors handling that is unpredicable.
It doesn't feel like shocks but I might be wrong.
What is the problem ?
Is it spring wind up ?
Can if be cured and if so how ?

Thanks.

Paul Humphries.

Post by **Innovator** » Mon Feb 05, 2007 5:19 pm

i do not know a definite answer but this thought process may help.....

It could be many things. Though to get rear wheel steer the outer loaded wheel will have to toe out. This could be a geometry problem, ie under roll the axle doesnt move straight up and down but in an arc.
Spring wind up on the outer wheel would make the spring effectively shorter causing toe in. Unless of course the inner wheel spring winds up.

Under roll the outer spring will compress, making it longer and the inner spring unladens making it shorter........could this be a problem?

I have experienced a delayed reaction from the rear without a panhard rod when changing direction suddenly.

Is your probelm under long steady cornering or under transients (ie changes)?

John

Post by **chickenjohn** » Mon Feb 05, 2007 6:25 pm

Try checking your tyre pressures, this seems to be the only thing (low tyre pressure in some tyres) that has ever given my cars strange handling.

Post by **jonathon** » Mon Feb 05, 2007 7:12 pm

Check your rubber axle pads are in good condition , the axle plates themselves are not corroded and that your U bolts are all tight. Obvious front and rear shackle bush check, and ahackle plates should be checked for wear. I go along with John re tyre pressures and John B re springs,maybe one side is worn more than the other or if welding has been done to either front or rear hangers, have these been sited in the correct position. A simple remedy for axle or spring wind up is a set of radius arms. PM me for details if you need them on this last point.

Post by **rayofleamington** » Mon Feb 05, 2007 7:21 pm

What is the problem ?

frost?
diesel spill on a damp road?

Post by **paulhumphries** » Mon Feb 05, 2007 7:32 pm

Actually there seems to be a slight list more to one side than another so I think I should investigate in case a spring is broke.
I only really notice the strange handling on the one, small, roundabout.
I come up hill and then go 3/4 of the way around before exiting.
I'd had it happen with other, far more powerful, RWD cars when pushing them too hard / fast / overloaded in boot etc on sharp turns but this is happening at low speed.
I also find that it's easy to spin one of the rear tyres when turning right from a standstill but not left !

Paul Humphries.

Post by **Peetee** » Mon Feb 05, 2007 8:22 pm

I also find that it's easy to spin one of the rear tyres when turning right from a standstill but not left !

That's the differential doing it's trick. It drives one wheel in preference to the other when on a slippery surface (I'm not sure but I think it's the drivers side that spins first).

The roads are really manky at the moment. My 7.5 tonner will oversteer when empty on some roundabouts. there is so much spilt diesel and oil that has not been washed away for two weeks and occasionally gets damped by cool mornings and moisture from overhanging trees.

Post by **Chris Morley** » Tue Feb 06, 2007 1:35 am

It's quite easy to fishtail a standard Minor in the wet, especially if the rear tyres are a bit worn, or if they are under-inflated. However it should behave itself as soon as you ease off the pedal . Same goes for axle tramp - be gentle with the accelerator when it's wet.

Post by **bmcecosse** » Tue Feb 06, 2007 10:33 am

Probably worn bushes and/or broken spring leaves - or more worryingly - rusty floor allowing the front of the spring to wander about as the floor flexes. Check it all out!

Post by **paulhumphries** » Tue Feb 06, 2007 7:40 pm

bmcecosse wrote:Probably worn bushes and/or broken spring leaves - or more worryingly - rusty floor allowing the front of the spring to wander about as the floor flexes. Check it all out!

Haven't checked anything yet but am 100% certain it's not hangers etc breaking away for the floor - all original and unwelded

Paul Humphries.

Post by **Willie** » Tue Feb 06, 2007 9:02 pm

Hope you are right, 'never been welded' usually means that it is about to fall to bits.

Post by **chickenjohn** » Wed Feb 07, 2007 8:46 am

paulhumphries wrote:
Haven't checked anything yet but am 100% certain it's not hangers etc breaking away for the floor - all original and unwelded

Paul Humphries.

You can only be sure about this by removing all the underseal in those areas. The sticky black stuff is use to hide all sorts of horrors and bodges.