Wanted to thank every one for their advice with my hub/shaft/key problems, have done about 100 miles with no breakdowns!

The rear of my car seems to be very unstable and seems to be steering by its self, it's had to describe the sensation but if you drive round an island and gently accelerate the car suddenly lurches over and feels as if the rear end has started to slide.

Any suggestions?!

Also is their any rule of thumb to setting the tightness of the front mount for the torque tube


Iain

Iain, I had a similar experience with a vintage car many years ago. It turned out to be the new at the time remould tyres which flexed on corners to the extent that the symptoms that you are experiencing were evident. Might have been too little pressure?
Dave

thanks Dave,

rear tyres were new about 100 miles ago and have about 25 psi in at moment

Book I have says 22psi

Hello Iain, what you describe sounds like normal Austin Seven ride quality.
The problem is caused by the fact that the rear axle is located only by the springs, which lengthen and shorten indepentantly due to humps and hollows in the road or the attitude of the body. This gives rear wheel steering, something usually found only on expensive modern cars! It can be very disconcerting at first but you soon get used to it and drive along see-sawing the wheel in the manner seen in old films.

Regards
Brian

Iain what make and size are the tyres?
Chris

it's quite a dangerous lurch as you turn in, if it was in my m3 i would be going for a dose of opposite lock and preparing for a sideways moment.

Are there any parts that ware on the axle like bushes that could be exaggerating this effect.


I am in the process of soaking the friction damper bolts in wd40 so i can tighten the rear dampers up a bit as soon as i can turn them.

one bit of info that may help is that if I brake when rolling backwards if feels as if the axle pushed the brakes on harder

using logic rather than any actual experience, would that not suggest that its the front axle that is moving, since if rolling backwards increases braking and its not something like the pads grabbing then the rear axle would move and move towards the driver, loosening the brake cables, but the front axle moving would move away from the driver, tighten the cable and increase braking. Just a thought.

After talking to a friend who drives a very fast vintage car with stiff springs and read the relevant parts of the Austin Seven Companinon. I have recently bound my rear springs with sash cord to stiffen them up and it has transformed the ride (no more bottoming) and handling (much more predictable. I was surprised to find that it took 12 metres (of a 12.5 metre) length to do each spring.

The heading to this topic makes me think you have reached the right conclusion already, namely there isn't much!

Andy B's logic is, I think, correct (though my brain hurts when I try to visualise what is happening) but you might get the "brakes on going backwards" phenomenon if you have a stretched or broken brake return spring.

Further to Julian's comment, I would advocate spring binding if you have the opportunity because it increases "interleaf damping" and mitigates any tendency of the main leaf to flex sideways. I would be inclined to wrap the finished job in Denso tape (greased bandage) to try and keep the water out.

Regards, Stuart

Hi Everyone,

Re spring binding with sash cord. Have a look at a recent lot offered for sale on eBay - Item No. 220168156056, see 4th photo down, 1st column - a very neatly cord bound rear spring, the front spring's had similar treatment. Are there instructions about to show how this particular lacing style is achieved?

Jeff

Stuart,

Thanks for the tip about Denso Tape, I'm off the plumbers/builders merchants right away.
Best wishes

Whereabouts in the Austin Seven Companion did you find an article about binding springs with sash cord, Julian?

John