Front end judder

Come here to ask for technical help and advice
User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Front end judder

Post by Aircooled Johnnyo » 24th March 2018 - 8:26pm

Hi all
Driving my 72 Fasty and when I brake there is a juddering coming from the front of the car. I assumed it was warped brake discs, so I changed the front discs, pads and bearings. However it has made no difference. Any ideas? Also whilst checking out my fuel gauge sender I broke the filament wire, does anyone know where I can get some?

Cheers

John

User avatar
purplepeter
Posts: 2090
Joined: 8th August 2006 - 4:41pm
Location: Bath,Avon/Corsham,wilts

Re: Front end judder

Post by purplepeter » 24th March 2018 - 10:36pm

For the sender, have a read of this: viewtopic.php?f=26&t=11983&p=58827&hili ... ome#p58827

Check the top arms of Your front axle for movement- it's explained in the Haynes manual or search on here

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 24th March 2018 - 10:41pm

Cheers Peter
Great help as always
John

User avatar
broady_6
Posts: 1712
Joined: 13th January 2009 - 9:55pm

Re: Front end judder

Post by broady_6 » 25th March 2018 - 9:38am

as above plus have you had your wheels balanced?
The sultan of swing

gracie
Posts: 95
Joined: 2nd January 2011 - 7:38pm
Location: Lanark, Scotland

Re: Front end judder

Post by gracie » 6th April 2018 - 10:09pm

and check your steering damper

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 6th August 2018 - 1:34pm

Hi again.
Soooooo, still got the judders :( Have changed :- Front brake discs, pads, inner and outer bearings, front shock absorbers, the ball joints were new anyway, new steering damper. I have adjusted the steering box to remove a little bit of slack. Still have the judders.
At the weekend I removed the top arms to inspect. Hopefully the attached photos work, but the arms look okay to me, they measured 32mm on the inner bearing surface and 35 mm on the outer bearing surface, the dimple in the end of the rod looks fine as well. The car is slightly lowered on the front splines if that would make a difference? I have road tested with different (original) wheels which made no difference, and I cannot find any play in the tie rods or pitman arm. Is it worth removing the lower arms to check for wear? Anyone have a good front beam available? HELP!!!!! AAAAArgh.

Cheers
John


Image

Image

Image

Image

Image
Last edited by Aircooled Johnnyo on 7th August 2018 - 1:11pm, edited 1 time in total.

User avatar
broady_6
Posts: 1712
Joined: 13th January 2009 - 9:55pm

Re: Front end judder

Post by broady_6 » 6th August 2018 - 3:33pm

Cant help directly with the issue, but ive sorted your image links out. You have to click the share arrow then copy the embed code to get the direct image link rather than just copying the page web address.

Have you tried running it at stock height, and have you had a proper wheel alignment done? What makes you certain is the front? I had a pulsing brake pedal many years ago and it was oval brake drums at the back causing the problem. Dont forget the back brakes will engage before the fronts, so you could try a light press on the pedal and see if it shows any signs
The sultan of swing

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 6th August 2018 - 4:26pm

Thanks Broady

I hadn't even thought about the rear brakes. If I gently pulled the handbrake on whilst moving that would confirm the rears ok or not?
Could you also tell me what the part in the picture of me pointing is for? It just bolts in, but should it me in a certain position?

Cheers

John

User avatar
purplepeter
Posts: 2090
Joined: 8th August 2006 - 4:41pm
Location: Bath,Avon/Corsham,wilts

Re: Front end judder

Post by purplepeter » 6th August 2018 - 5:12pm

That holds the other end of the Torsion bar

User avatar
broady_6
Posts: 1712
Joined: 13th January 2009 - 9:55pm

Re: Front end judder

Post by broady_6 » 6th August 2018 - 5:48pm

Aircooled Johnnyo wrote:
6th August 2018 - 4:26pm
Thanks Broady

I hadn't even thought about the rear brakes. If I gently pulled the handbrake on whilst moving that would confirm the rears ok or not?
Could you also tell me what the part in the picture of me pointing is for? It just bolts in, but should it me in a certain position?

Cheers

John
It might do, gotta be worth a try. But with the hydraulics you would get more feedback through the pedal
The sultan of swing

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 6th August 2018 - 6:33pm

Righto

Cheers

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 6th August 2018 - 6:42pm

Pete
Why the odd shaped bracket thingy?

User avatar
purplepeter
Posts: 2090
Joined: 8th August 2006 - 4:41pm
Location: Bath,Avon/Corsham,wilts

Re: Front end judder

Post by purplepeter » 6th August 2018 - 7:38pm

Ask Dr Porsche!
I couldn't say for certain, but maybe it prevents movement of the arm below it, otherwise it's effectively a bloody big washer that'll take quite a lot of strain
You know the torsion bars cross each other?
Have You checked for lateral movement on the top arms?/ what state are Your thrust washers in?

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 6th August 2018 - 8:18pm

Good old Ferdi!
I detected a small amount of lateral movement, maybe 0.5 of a mm. I don’t know what to look for for thrust washer wear, any images I could compare?

User avatar
broady_6
Posts: 1712
Joined: 13th January 2009 - 9:55pm

Re: Front end judder

Post by broady_6 » 6th August 2018 - 8:40pm

Not something you can compare image wise. Its to be measured, ill post the info from my bentley manual when i get chance. what youve done is exactly how you would check for it though.

I believe the funny shape washer have a tab on the front which acts as a bit of lock to stop the bolt from undoing
The sultan of swing

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 6th August 2018 - 9:08pm

Cheers Broady

User avatar
Editor
Posts: 5466
Joined: 10th October 2004 - 8:52pm
Location: Pensford, Bristol
Contact:

Re: Front end judder

Post by Editor » 6th August 2018 - 9:37pm

If you grab the top of each front wheel and pull and push out and in, is there any slack? If so that can be taken up in the upper bar. There's an M8 bolt and lock plate on the the end, and the slack is caused by wear on the plastic wear plates.
Dave.

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 7th August 2018 - 12:26pm

This is a pic of the beam end/thrust washer?
Does this shed any light on the possible wear?
When I grabbed the wheel I couldn't feel any movement by the way.

John
[imgImageThrust washer by J Marchant, on Flickr[/img]

User avatar
purplepeter
Posts: 2090
Joined: 8th August 2006 - 4:41pm
Location: Bath,Avon/Corsham,wilts

Re: Front end judder

Post by purplepeter » 7th August 2018 - 1:43pm

Yes, that's it- there should be one each side of the beam
I use a chunk of fence post & a lump hammer on the passenger side top arm (Fence post gives you freedom to swing without whalloping the wing) to push all of the freeplay over to the drivers side, before tightening the little bolt.( less work/strain on the bolt & enables You to do the job without an assistant to check)
Then, obviously, get as much grease into the beam as possible.

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 7th August 2018 - 3:21pm

Pete

Do you think that the thrust washer (which I assume is the silver round part with the slots in it) is showing wear? Or any of the other parts in the pictures?

Cheers

User avatar
broady_6
Posts: 1712
Joined: 13th January 2009 - 9:55pm

Re: Front end judder

Post by broady_6 » 7th August 2018 - 4:00pm

That's thrust washer looks in good fettle, check the other side foe the same.

I will give you the book procedure for adjustment later. Peters approach is ok, but those washers can crack so id avoid hitting them if you can.
The sultan of swing

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 7th August 2018 - 4:04pm

Thanks everyone

John

User avatar
broady_6
Posts: 1712
Joined: 13th January 2009 - 9:55pm

Re: Front end judder

Post by broady_6 » 7th August 2018 - 5:51pm

Ive done them super large so you can download and zoom in.

Image

Image

Image
The sultan of swing

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 7th August 2018 - 7:17pm

Thanks Broady

User avatar
Aircooled Johnnyo
Posts: 112
Joined: 11th October 2012 - 8:07pm

Re: Front end judder

Post by Aircooled Johnnyo » 30th August 2018 - 8:54pm

Wellllll
Broady you are today’s genius.
Rear brake drums were out of round, new shoes and drums and she stops perfectly. Transformed the driving experience completely, thanks to everyone for your help and a gold star to Broady😀
On another note has anyone got an image of how the battery positive cable routes through the body to the starter motor. Mine goes through the floor pan and ou and over the rear axle, sounds wrong to me, surely it would chafe on the axle?

Thanks again

John

Post Reply