Stopping front wheel judder.

[Forumadmin]

Paul Rennie has asked we look at the Bradford front wheel judder problem at next weekend's Technical Days. Has anybody a solution to the problem please? Pictures, diagrams and write up would be great.

Apparently the Jowetteer or perhaps Flat Four has an article.

[george garside]

before considering anything else it is essential that the kingpins are spot on and that free play at the steering wheel is minimal ( factory 1/2 inch) so aim for no more than 1' inch! . The lock to lock movement should also be smooth with no tightness towards full lock.

The springs may need resetting as if they have sagged the caster angle will be wrong. A cure to this can sometimes be had by fitting wooden wedges between axle and spring. Tracking also needs to be spot on as do wheel bearings, trak rod and drag ling ends etc.

A steering damper can be fitted but it is arguable that if everything in the steering department is as it should be a damper will not be needed and for what its worth I never found one necessary even driving long distances at 45/55mph i.e. ''pied a plancher '' or whatever the expression is!

for those who wish to add a damper I understand that the one from a VW beetle ( the proper rear engine one!) will do the trick if connected between the track rod and chassis. I think they are available brand new from the numerous beetle specialists.

george

[David Kemp]

You probably don't have time but the New Zealand club did a very good article on Bradford steering issues, at the end of it claimed, the Bradford should steer like a period MG!
I can't unfortunately remember who wrote the article.

[Forumadmin]

Bradford Wheel Shimmy



In 1950 my Dad bought a brand new Bradford Drive away Chassis and built a very nice 4 door saloon body on it and this was our family car for 8 years (when he bought an immaculate low mileage Javelin which incidentally he had till he died). Very early in use he drove over a railway line and the Bradford shimmied terrifying and Dad thought the world had come to an end! He had the car straight back to the agents but it still shimmied in certain circumstances during his ownership. Therefore I can say and it has been my subsequent experience that it has nothing to do with worn kingpins, wheel bearings, tie-rod ends or steering box because as I say they did it from new! However it pays to have the correct set (curve) of the front springs as this controls the caster of the front wheels. Similarly wedges slipped between the axle and the springs can alter the caster. The only known cure that I know is to fit a Volks Wagon steering damper, one end to the axle using the hole opposite the brake compensator and the other end clamped to the tie rod. This however does make the steering just a little bit heavier. The funny thing is they don't all do it. I have driven my Bradford regularly now for around 22 years and I have never experienced a shimmy - touch wood!! Others will do it frequently while others on rare occasions. That's all I have to say.



Cheers,

Vic Morrison.

[Forumadmin]

Not a Bradford nutter but there are 2 schools of thought I understand.

1 Just get everything right upfront or fit a VW damper

Alan Stanley

[Forumadmin]

In October 1947 Jowett Issued a bulletin relating to 10hp cars with this problem. 10hp axles are essentially identical to the Bradford. This recommends fitting wooden packing wedges between the spring and the axle. These to be 1/8" tapering to zero and fitted with the 1/8" to the front to cure this problem. I know it is common on Bradfords and I believe this usually solves it. All Silentbloc bushes need to be in good condition.

Paul Beaumont

[Forumadmin]

Hi Keith,

The pics of the VW Kombi steering damper fitted to my Bradford Ute are in TOPIC the Gallery here. It is secured to a bracket fitted to the L/H U bolt and two clamps brackets (a bit of overkill one would do the trick) and a plate bolted to the track rod.

Mounting the steering damper in this position allowed it to be tucked up behind the front axle and to operate parallel to the track rod.

Prior to fitting the steering damper I had done all the usual things such as spring shackle bushes, king pins, steering box, axle wedges, and wheel alignment, the wheel wobble still occurred occasionally, but only on a bad road surface.

The steering damper has fixed the wheel wobble problem. The steering damper was purchased new from our local VW specialist for about $90.00(NZ)


Regards

John Wolf

[george garside]

[quote="Forumadmin"]Bradford Wheel Shimmy



In 1950 my Dad bought a brand new Bradford Drive away Chassis and built a very nice 4 door saloon body on it and this was our family car for 8 years (when he bought an immaculate low mileage Javelin which incidentally he had till he died).


Cheers,

Vic Morrison.[/quote]

Vic, Do you have any photos of your dads Bradford saloon and if so can you post them on here

george

[richard turner]

Don't forget to ensure that the silent bloc bushes are in good order.

[Jack]

All,

By silent bloc bushes are we talking about the bushes in the eyes of the leafsprings?

Just wanted to check. Are there polybushes available for these, and is this considered a good idea for the Bradford?

Jack.

[Forumadmin]

Note that Jack's Braddie already has the wedges under the front leaf springs, I think in metal.

[Keith Clements]

Hi Keith,

John Wolf has summed up the situation accurately. There seems to be a critical combination of speed and road surface which initiates the problem and without warning. I have found that at a speed of approx 25 mph on a rough road surface the problem can occur. I have not yet fitted a steering damper to my Bradford, but probably will. Having attended to the obvious things I have had the problem occur after a couple of thousand miles, while recently on the way to the ferry in Melbourne I had the problem occur after the first 10 miles. I travelled a further 530 miles without any steering problems.

My thoughts are:

1. reduce all wear in the suspension and steering systems.

2. set toe in

3. correct castor - this can change as the front springs settle

4. check front tyres for out of round - I have had this cause front wheel wobble - also have wheels and tyres balanced

5. to be certain of a complete remedy fit a steering damper.



from experience with another vehicle - not a Jowett - that while alI the factors mentioned are important I believe the fitting of a steering damper could be the most significant for a lasting solution to the wheel wobble problem.

regards,

Brian Hehir

[Jack]

Do we know what actually causes the wobble? Idle poking around the front end last night got me thinking that the leaf springs extending backwards (on the shackle) might cause the steering to be affected if driving over a rough surface - as the suspension travels up and down it gets into a rhythm of sorts and as that bounces it affects the steering. One or both sides could be moving backwards and forwards with the suspension travel and that would affect the steering wouldn't it? The bit I am trying to work out is why the wedges fixes the problem, but clearly there are many owners who have benefited from this.

Hopefully with mine having the wedges in place already this won't be an issue, but it does sound like we have a solution. New tyres and good balancing hopefully will ensure we are running as smoothly as can be expected!

Jack.

[george garside]

I agree that fitting a steering damper should eliminate the problem but it does smack a bit of treating the symptoms rather than the cause. In tens of thousands of miles with Bradfords I have never experienced the problem but the one and only Ten I ever owned was very good at 'wobbling' despite being fitted with wedges.

george

[ian Howell]

Jack posted : - why the wedges fixes the problem,

I think this is because inserting the wedges moves the point of contact of the tyres with the road, a little further back so increasing the 'castor' effect.

This might also make the steering a little heavier, so be careful.