Cobra (re)build

  1. mylesdw

    mylesdw Member

    Messages:
    656
    New Zealand
    I have new heads to go on so snapped bolts would not be an urgent problem but at the moment I think most would just round off. I'm on the plus-gas method and will retry in a week or so.
     
  2. angellonewolf

    angellonewolf Member

    Messages:
    3,955
    Location:
    bristol england
    dont for get unscrew then a turn back tight a turn so say if you keep unscrewing all the crud gets to one point and threy get tight strip threads giving the turn back spreads the crud and then clean threads after you hope removed the parts that did undo
     
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  3. mylesdw

    mylesdw Member

    Messages:
    656
    New Zealand
    Went down to the local secondhand shop and picked up a handful of 7/16" sockets for 50c each including this sturdy 6-point one which I butchered (reduced the outside diameter) in the lathe to get the clearance needed. This got another three bolts out so four of the twelve left now - the awkward ones with really poor access.

    P1040039.JPG
     
    brewdexta likes this.
  4. Wallace

    Wallace Member

    Messages:
    6,099
    Location:
    Staines, Middlesex, England.
    Is the engine coming out to be stripped? If so, I would take the heads off with the manifolds on if possible and work on the bench.
     
  5. mylesdw

    mylesdw Member

    Messages:
    656
    New Zealand
    Not an option I'm afraid. It is a tri-Y design with the third Y down under the footwell.

    The pipes are one of the very few things on the car that I did not do myself. I just took it to a place down on the south coast and collected the car with the exhaust built and installed. I do begin to wonder how they got the pipes in and out - it's very tight!

    I've bought an 8-sided ring spanner on eBay and hope that this will help get one or two more.
     
    chris pruteanu likes this.
  6. CornishPete Member

    Messages:
    406
    Location:
    Huddersfield
    I'm sure when that vet/mechanic guy built a cobra it was about 10 grand or something like that, definitely less than buying a new fiesta! When did building a sumo cobra kit car cost £30k? I always fancied a gt40 but they're closer to £50k now!
     
    dobbslc likes this.
  7. Cal Member

    Messages:
    305
    Bristol, UK
    Induction nut heater.
     
  8. Cal Member

    Messages:
    305
    Bristol, UK
  9. mylesdw

    mylesdw Member

    Messages:
    656
    New Zealand
    Ran out of patience and cut the remaining bolts off with the grinder.

    I'm fighting with numerous things that I put together nearly thirty years ago without any real thought about how they would come apart again -

    1. To get the gear stick off I need to remove the carpet
    2. To remove the carpet I need to remove the roll hoop and strut
    3. The roll hoop is completely stuck in the chassis. I currently have the rear of the car hanging by roll hoop and an engine hoist with no sign of movement. I going with penetrating oil for the moment...
     
    Wallace likes this.
  10. Wallace

    Wallace Member

    Messages:
    6,099
    Location:
    Staines, Middlesex, England.
    Sometimes it’s fun going through an old project and finding your previous work! :D I’ve done it a couple of times, looked at bits and wondered what the heck I was thinking of at the time. For me, it was mostly down to lack of resources or equipment at the time.
     
    dobbslc likes this.
  11. mylesdw

    mylesdw Member

    Messages:
    656
    New Zealand
    Same with me, I have so much more space, knowledge and equipment now. I built the car in a single garage with only hand tools; the more I take apart the more it's turning into a big job!
     
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  12. slim_boy_fat

    slim_boy_fat Forum Supporter

    Can't you carefully cut the carpet round the other bits? :dontknow:
     
  13. mylesdw

    mylesdw Member

    Messages:
    656
    New Zealand
    I could but at the moment I'm keen to fix the many things that I know 'could be done better' and if I end up taking the body off, the roll bar has to come out.
     
    slim_boy_fat likes this.
  14. mylesdw

    mylesdw Member

    Messages:
    656
    New Zealand
    Removing this roll-bar is proving a real challenge. I have put huge force on it both with a hoist and with a scissor jack without the slightest success. I will try penetrating oil for a while; after that I will have to cut a large hole in the panel behind the seats so that I can get a grinder in there to cut it off. It is simply two large diameter stainless steel tubes pushed into steel sockets but it is well jammed.
     
  15. Cal Member

    Messages:
    305
    Bristol, UK
    Ratchet straps are your friend here.
     
  16. mylesdw

    mylesdw Member

    Messages:
    656
    New Zealand
    But what can I pull on? I have lifted the back of the car up by the roll bar and no movement; I would need something to anchor it to the ground.
     
  17. 8ob

    8ob Member

    Messages:
    3,682
    Location:
    moscow on thames
    No pics? A stainless rollbar hoop in a tight mild steel socket is probably never going to budge, that will be as good as welded after all these years. Can these sockets be got at with a thin disc? Was thinking a slice down two sides and try a wedge to open them up a tad, could always be replaced/sorted later on.

    Bob
     
    Woody.v8 likes this.
  18. Woody.v8

    Woody.v8 Blue gluer

    Messages:
    2,919
    Location:
    staffs
    Can you get at the sockets with a BFH, working around them to stretch the steel ever so slightly?
     
  19. Cal Member

    Messages:
    305
    Bristol, UK
    Sorry, I assumed that you were familiar with the trick to use a ratchet strap or straps to transversly load the hoops, we used to do this to get them in and out.

    I don't have a picture so I will try a text picture, hoping that the text format doesn't mess up, the theory is you use the ratchet straps to close the ends of the open loops and this brakes the loops natural expansion.


    HHHHHHHHHHHH
    H H
    H H
    H H
    H strap here H
    H H
    H H
    H strap here H
    H H
    SIDEWAYS LOAD ON THE BASE BREAKS THE FRICTION

    If that makes any sense at all?
     
  20. HopefullySoon

    HopefullySoon Member

    Messages:
    510
    Location:
    Heywood
    Not nessacerily to the ground but against its self .

    Rough idea of what I’m thinking is ratchet strap rear wheels / fab up onto a kind of structure

    ___^___

    Brace up , support and with what 8ob said should break free with some ratchet straps
     
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