Axle Wedges

Old Fogey UK
Old Fogey UK Expert Adviser
There's not much caster action in the steering on my '34 H.
The wheels don't straighten up from a turn unless I pull the wheel round - is this as it should be ?
According to the Procedure Manual, caster can be adjusted with axle wedges but doesn't explain in any detail how it's done - any tips please ?
The ROC lists these wedges in its members' parts list but they're sold out at the moment.
Are there any US or other sources for them ?
Alternatively, has anyone got the specifications for them so I could get some made up ?

Comments

  • These could be wedge shaped pieces metal that you install between the axle and the leaf spring to lean the axle back and give you more caster. The same type of thing is used on the rear end to change the pinion angle.
  • Old Fogey UK
    Old Fogey UK Expert Adviser
    54coupe said:
    These could be wedge shaped pieces metal that you install between the axle and the leaf spring to lean the axle back and give you more caster. The same type of thing is used on the rear end to change the pinion angle.
    I think you're right. Problem is where to get them and how to fit them properly.
  • 54coupe said:
    These could be wedge shaped pieces metal that you install between the axle and the leaf spring to lean the axle back and give you more caster. The same type of thing is used on the rear end to change the pinion angle.
    I think you're right. Problem is where to get them and how to fit them properly.
    Search "pinion angle shims"... I see them on amazon... four wheel drive suppliers sell them as well. Most modern applications have a wider spring than our Hudsons. You may have to narrow them. They come in various sizes, so you will have to decide how many degrees you want to change the king pin angle.
  • For fitting, you loosen the U-bolts so there is space between the axle and the spring. Then slide the shim in that space and tighten it down again. The locating pin in the spring will go through the shim and into the axle, keeping it located on the spring. I suggest loosening both sides, putting the shims in, then tightening both sides, that way you are not trying to twist the axle by doing one side at a time.
  • If I were doing it on my own car, I would only do 2-3 degrees, then drive it to see if I was happy with the change.
  • bob ward
    bob ward Senior Contributor
    The head of the spring centre bolt locates the axle to the spring, the amount of engagement is maybe 1/4". Adding a shim reduces that engagement and sometimes requires a new centre bolt with a taller head to maintain adequate engagement. DAMHIKT.
    And of course, its not impossible to install a 34/5 front axle back to front  :D
  • Geoff
    Geoff Senior Contributor
    And to increase positive caster the wedges have to go under the back of the spring mount.  I would recommend though that you get a wheel alignment done  first, instead of flying blind.  
  • Speedway Motors has axle wedges.
  • Old Fogey UK
    Old Fogey UK Expert Adviser
    Thank you all for the advice, especially Bob Ward for his private message.
     I think I may have been the architect of my own problem here.
    When I restored the car, I encountered all sorts  of Fred Flintstone fixes by the previous owner, including a large thick washer driven in under one side of the front axle.
    Apparently, this is a crude way of adjusting caster angle.
    In my ignorance, I knocked it out - it all goes to show that a lawyer assisted by a retired doctor aren't necessarily always the best people to restore an old car !
    Assessing which are the right wedges and installing them doesn't sound as easy as fitting new swivel pins and radius rod ends, so I'll be leaving the fix to the professionals in this instance.

  • terraplane8
    terraplane8 Senior Contributor
    I had some of these steel wedges I bought from the Railton Club fitted to my ‘33 Terraplane to see if it helped it to reduce wander, ie by creating more castor. But it didn’t make much difference apart from increasing steering effort a little at low speed so I removed them. They are easy to fit actually.
  • Old Fogey UK
    Old Fogey UK Expert Adviser
    I'm going to book the car in next week at the local old car specialist for a full steering geometry check to ascertain exactly what the problem is - and then I'm going to get him to fix it.