metal tyre valve caps -- beware

Discussion in 'Tech/Mech General' started by Euromobil, Jan 23, 2010.

  1. Euromobil

    Euromobil Read Only Funster

    Joined:
    Jun 23, 2009
    Messages:
    76
    Likes Received:
    0
    Location:
    hampshire
    thought I would treat the car to a set of shiny ali valve caps to tart it up a bit. Looked really nice, ' til I went to check tyre pressures after the bad weather.

    Plus gas---WD40---heat----mole grips--- nothing would shift them, the salt had corroded the caps to the valve stems. In the end I filed a groove through so I could soak with penetrating oil overnight, so back to plastic for me.
     
  2. old-mo

    old-mo Funster Extra Special Life Member

    Joined:
    Oct 16, 2008
    Messages:
    12,715
    Likes Received:
    38,574
    Location:
    Dorset
    Next time try smearing a bit of vaseline on the thread before screwing them on.. :thumb:

    Happened a couple of times on my M/bikes,, and no I did not practice what I preach.. :Doh:

    Do now though.. :thumb:
     
  3. pappajohn

    pappajohn Funster Life Member

    Joined:
    Aug 26, 2007
    Messages:
    29,455
    Likes Received:
    16,884
    Location:
    YO11 2BD
    never really gave that a thought....

    a light smear of grease on the valve threads would stop it happening.

    the ally wheels on my pickup 'stuck' to the hubs in the same way.
    a 2lb lump hammer and block of wood eventually released them.
    now they have brake grease smeared on the 'mating' surfaces.
     
  4. Euromobil

    Euromobil Read Only Funster

    Joined:
    Jun 23, 2009
    Messages:
    76
    Likes Received:
    0
    Location:
    hampshire
    Next time try smearing a bit of vaseline on the thread before screwing :


    Great idea , but what about the valve caps:
     
  5. derekfaeberwick

    derekfaeberwick Read Only Funster

    Joined:
    Dec 1, 2007
    Messages:
    1,131
    Likes Received:
    7
    Location:
    Berwick
    The local scrots don't have a problem removing them.

    Truck and trailer, all over the country, there they were, gone!:Angry:


    The bar stewards like them on their bikes! [​IMG] that's what they need!:Cool:
     
  6. VMax666

    VMax666 Read Only Funster

    Joined:
    Nov 26, 2009
    Messages:
    172
    Likes Received:
    1
    Location:
    Knutsford
    Aluminium + Salt = Corrosion
    Same reason Aluminium fittings on brake lines for road bikes are a no-no.
    The engines on Brit bikes used to suffer, steel frame/ alloy engine and salt are not compatible unless you fit a sacrificial anode. I am sure someone will know the electrochemical formulae.....:Smile:
    VMax
     
  7. warwick

    warwick Read Only Funster

    Joined:
    Sep 16, 2008
    Messages:
    113
    Likes Received:
    0
    Only steel caps should be used on steel valves, they are more expensive but are compatable.
     
  8. pappajohn

    pappajohn Funster Life Member

    Joined:
    Aug 26, 2007
    Messages:
    29,455
    Likes Received:
    16,884
    Location:
    YO11 2BD
    can you ellaborate please...
    plastic caps, being inert, are standard fit the world over by every car manufacturer today. with perhaps the odd exception on luxury motors.
     
  9. NEV3

    NEV3 Read Only Funster

    Joined:
    Feb 11, 2008
    Messages:
    30
    Likes Received:
    1
    Location:
    North East Wales
    I too had this problem on the wifes Smart car (our toad) last winter (2008/2009).
    Tried to check tyre pressures and ended up having to replace all four valves due to corrosion induced by road salt. Garage mechanic then advised me "never ever fit alloy caps to standard metal (brass, steel etc) valves.(electrolosis he said). The valve caps were the right colour you see! The scrotes only tried to nick em in the summer months!

    NEV3
     
Loading...

Share This Page