Section : Overdrive

Overdrive not engaging 

Posted By : Martin Neal, 04-Jan-2004, 06:39pm

• Overdrive not engaging 

  Posted By : Nigel Gibbins, 04-Jan-2004, 07:34pm

  Try the Canleys webby - it has a section about overdrive problems...
  
  http://www.canleyclassics.com/infodatabase.asp?top...
  
  take your pick....
  NiG

  • Overdrive not engaging 

    Posted By : David Styles, 05-Jan-2004, 10:55am

    have you checked your gearbox oil lately ?
    
    sporadic then stopping working can mean lack of gearbox oil.
    
    Especially if when you say sporadic, you mean, it stops working during a long run when it gets hot.
    
    I'd top up the gearbox oil first.
    

    • Overdrive not engaging 

      Posted By : Martin Neal, 05-Jan-2004, 02:34pm

      Well, it was topped up in August of last year, but the gearstick's been a bit stiff of late (I had put it down to the cold) Overdrive didn't engage properly from the start for a short period a few weeks back. It kept going in and out rapidly before i decided that whatever it was doing couldn't be good and swiched it 'out'. now it won't engage at all.
      
      I currently have her on ramps and axle stands to change the exhaust pipe and diff and I noticed the gearbox was very oily (on the outside) - a leakage methinks. A top up may well be in order.
      
      Also is there a way to test it without going for a long drive?
      
      Martin N
      73 Emerald Spit

      • Overdrive not engaging 

        Posted By : David Styles, 05-Jan-2004, 03:49pm

        "kept going in and out rapidly" doesn't sound like low oil.
        
        If I've got it right... its held in by oil pressure via a little pump !
        
        when the level gets low... there's not enough oil around for the little pump to keep the pressure up...
        
        the only reason I mentioned "long drive" is that when it gets marginal, and the oil gets hot... its hard for that pump to keep the pressure up as the oil goes all runny !
        
        unless its weirdly marginal and the pump can/can't/can... find oil... then usu it just cuts out once hot... until the oil is just way too low for it to find any...
        
        anyways.... just letting you know that the "in and out rapidly" sounds less like oil level to me.
        
        Still... can't hurt to top it up can it ?
        
        

• Overdrive not engaging 

  Posted By : Philip Wright, 04-Jan-2004, 08:54pm

  Hi there
  
  It sounds to me like a problem with the inhibitor switch, which only allows the o/d to be engaged in third and fourth gear. These are often covered in oil and lead a hard life, and often give problems on many cars [including mine]. The switch is identical to a reverse light switch, so if you have one of those around, it's a nice easy fix. Unfortunately the gearbox tunnel cover has to come out. The bracket which attaches the switch to the gearbox also bends and prevents the button on the switch from being depressed fully.
  
  Hope you get it fixed
  
  Phil - '74 Spitty