Register now to get rid of these ads!

Oops, broke it again.

Discussion in 'HA/GR' started by spanners, Aug 15, 2021.

  1. spanners
    Joined: Feb 24, 2009
    Posts: 1,224

    spanners
    Member

    Spanners had to get the spanners out again. Local racing has been cancelled again because of the 'you know what virus' so I thought I'd do some driveway testing. A couple of spirited runs to check out the new mesh screens I made for the carby intakes. Wasn't happy with them so I deleted them and it made a huge difference. Put the racecar back into the trailer and had arranged to get the certification done in a couple of weeks. When I spoke to the certifier he told me to make sure the kill switch actually killed the engine. Back out to the trailer, fired the car up and found it didn't kill the engine. No excessive revs were used in the testing.
    Changed the alternator wire and hit the starter. Horrible internal clunk. Changed the starter, wouldn't turn the engine. Rolled the car out of the trailer and into the shed. Pulled the plugs and engine wound over. Plugs back in, hit the starter, it fired and locked. Pulled the sump and everything looked good until I rotated the flywheel by hand.
    DSC_0356.JPG
    Matching bookends! Good thing it didn't happen at full song. No debris in the sump but due to state wide lock down I can't get another crank ground so I changed out the dead engine and put the spare in. Shit happens.
     
    Lil32 and Crosley like this.
  2. Crosley
    Joined: Mar 3, 2001
    Posts: 1,047

    Crosley
    Member
    from Aridzona

    A common failure point on the crankshaft?
     
  3. Old6rodder
    Joined: Jun 20, 2006
    Posts: 2,523

    Old6rodder
    ALLIANCE MEMBER
    from SoCal
    1. HA/GR owners group

  4. spanners
    Joined: Feb 24, 2009
    Posts: 1,224

    spanners
    Member

    Yes, it's the Archilles Heel of the Holden Grey. They never did like being over revved. The speedway blokes used to break heaps of them but mostly due to the constant on-off the throttle. I'm starting to wonder if my problem is the very light flywheel I'm running. Mind you, this engine has done over 120 passes since the last broken crank, doing something it wasn't designed for so I can't complain.
    Yes, they are a cast crank. There was a place over here that would build billet cranks for these old engines but the price tag was around the $2,000 mark, way too much for my retired pockets.
     
    Lil32 likes this.

  5. Old6rodder
    Joined: Jun 20, 2006
    Posts: 2,523

    Old6rodder
    ALLIANCE MEMBER
    from SoCal
    1. HA/GR owners group

    Was the cast crank turned down? Cast cranks don't much like having the surface removed, sometimes gives'em improved fracture starting areas.
     
  6. spanners
    Joined: Feb 24, 2009
    Posts: 1,224

    spanners
    Member

    Yes, but only 10 thou for bearings. Where they break is no. 6 journal through the oil gallery.
     
  7. BS!
    Joined: Mar 17, 2010
    Posts: 142

    BS!
    Member

    Ouch. Are you running a girdle or main bearing bridges at all? What do you rev yours too?
     
  8. spanners
    Joined: Feb 24, 2009
    Posts: 1,224

    spanners
    Member

    No girdle or bridges. Quite often sees 6500 but has been known to run off the dial if I miss a gear.
     
    Lloyd's paint & glass likes this.
  9. BS!
    Joined: Mar 17, 2010
    Posts: 142

    BS!
    Member

    Hahaha glad I’m not the only one who has done that
     
  10. THE FRENCHTOWN FLYER
    Joined: Jun 6, 2007
    Posts: 3,642

    THE FRENCHTOWN FLYER
    Member
    from FRENCHTOWN

    Do you have a vibration damper on the snout? If not that will help, even if you have to adapt one from a similar engine.
     
  11. spanners
    Joined: Feb 24, 2009
    Posts: 1,224

    spanners
    Member

    Yes, there's a Ross Racing harmonic balancer on the snout. These engines only have 4 mains so they were never designed for this sort of punishment. They usually break through the oil gallery. In an ideal world I'd love to have the money to have a forged crank made but I'd have to sell both testicles plus an arm and a leg to do it.
     
    Crosley likes this.
  12. THE FRENCHTOWN FLYER
    Joined: Jun 6, 2007
    Posts: 3,642

    THE FRENCHTOWN FLYER
    Member
    from FRENCHTOWN

    With hand controls fitted up you only need one hand to drive.
     
  13. twenty8
    Joined: Apr 8, 2021
    Posts: 304

    twenty8
    Member

    And the weight savings may gain you a few hundredths............:D
     
  14. spanners
    Joined: Feb 24, 2009
    Posts: 1,224

    spanners
    Member

    I like your thinking but with only one leg I'll go around in even more circles than I do now. As for the testicles, what to scratch when pondering?
     
    Old6rodder likes this.

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.