Overdrive inhibitor switches

[GT6boy]

I wonder if i'm alone in wondering if the quality of the OD inhibitor switches is temperature sensitive? :-/
My J type OD has already had one replacement switch fitted as a precaution, but that now is exhibiting the same potential for going open circuit/OOA on long hot runs?
I've fiddled with the adjustment and got it as corase as I can, but its a fine line between that and the actuating arm failing to sweep across the round switch surface and impacting on its side.
You can get it too work whilst mobile, by gentle manouvering of the gear lever, but then once the drive trian is cold- its back to working normally! :X

[Paudman]

Possibly a short in one of the wires, aggravated by heat?

[tiggrr1]

Bruce is your gearbox tunnel insulated on the underside with the bitumen/silver foil type of stuff.

My mate Gaz was having all sorts of over drive issues, old crumbling wiring and it also turned out that the inhibitor switch was being shorted out by the foil on the underside of the gearbox cover insulation material.

[GT6boy]

No silverbacked NASA insulation, just good old fashioned fibreglass in a clear polythene bag 8).
Not aware of any wiring shorts- it is definitely the case that the gear lever extension arm isn't depressing the 'tit' sufficiently. A little manipulation of the gear lever and the 'tit' works until you let go of the gear lever. It never fails like this when the whole transmission system is cold, only when it is sufficiently hot from a good run- but then not always: it's very disappointing when it happens.

[Tim Bancroft]

Examine the ball bearing in the switch and ensure it is totally round.

I had exactly the same problems, solved by fitting a new switch and enlarging the holes in the bracket that the switch mounts on where it bolts onto the gearbox extension.

If doing a trip of any duration (RBRR, 10CR etc), I always carry a spare switch!

[GT6boy]

I'll get a spare switch Tim. I fancy doing a resistance test on the new switch and then gently heat it up and see if that makes any difference to its operation.

[Hugh]

I think I have the same problem with my O/D but it's slipping even when cold and much worst when hot but only above 3500 rpm :-/

[rotoflex]

timbancroft61 wrote:

Examine the ball bearing in the switch and ensure it is totally round.

I replaced one that did not let the ball bearing all the way out any more.  
It was a years-old switch, so there may be some issue related to design that is not new.

[StagNL]

908 wrote:

I think I have the same problem with my O/D but it's slipping even when cold and much worst when hot but only above 3500 rpm :-/

Similar to my OD woes a year ago.  Engine thrust bearing was completely gone.  OD slipped only after 15 mins of driving and usually when accelerating hard or out of corners.

Julian

[Hugh]

699 wrote:

Similar to my OD woes a year ago.  Engine thrust bearing was completely gone.  OD slipped only after 15 mins of driving and usually when accelerating hard or out of corners.

Julian

Fooking hell what size job is that going to be seems like a plauge of gearbox problems have been sent upon us GT6 suffers :-/ If I wanted a car that wouyld keep having faults that I would have to repair all the time I would have bought a Rover ;D :X

[Hugh]

Have fixed the o/d problem it was the switch wires worn through causing a short circut , so repaired the wires and put extra insulation over the whole cable. Drove car and all is working perfect so I got of light  :)

[Lord Sorbington]

http://www.youtube.com/watch?v=lV9Gc39o_tY

[Hugh]

sorbs wrote:

http://www.youtube.com/watch?v=lV9Gc39o_tY

What the fook has this to do with an o/d switch problem  :-/

[GT6boy]

908 wrote:

Have fixed the o/d problem it was the switch wires worn through causing a short circut , so repaired the wires and put extra insulation over the whole cable. Drove car and all is working perfect so I got of light  :)

Well done Hugh :).
Mine was exhibiting the temperature related vaguries again yesterday(mad). I'll nip th etunnel cover off in due course. The horn gave up the ghost too, but that was merely a high resistant connection on the output from the horn relay :).

[Lord Sorbington]

908 wrote:

What the fook has this to do with an o/d switch problem  :-/

A repaired overdrive is cause for celebration and what better way to celebrate than through the medium of music?

You can now use maximum overdrive whenever you wish.

[Hugh]

sorbs wrote:

A repaired overdrive is cause for celebration and what better way to celebrate than through the medium of music?

You can now use maximum overdrive whenever you wish.

;D ;D ;D

[thescrapman]

908 wrote:

What the fook has this to do with an o/d switch problem  :-/

I thought it was going to be this

http://www.youtube.com/watch?v=lJmBPCYt5LY

Well you probably haven't, yet.

[Hugh]

908 wrote:

;D ;D ;D

;D ;D ;D now I get it

[Hugh]

thescrapman wrote:

I thought it was going to be this

http://www.youtube.com/watch?v=lJmBPCYt5LY

Well you probably haven't, yet.

His lordship I get his ;D
  but I do not get yours  it's been done already (think)(think)(shhh)(shhh)(shhh)(shhh)(shhh)

[thescrapman]

908 wrote:

His lordship I get his ;D
  but I do not get yours  it's been done already (think)(think)(shhh)(shhh)(shhh)(shhh)(shhh)

Well, Bruce has not yet removed his tunnel, so he has not seen anything yet, that may give him a clue as to what the problem might be, yet.

Ah, whatever.

Colin

[ferny]

Surely this makes sense?

http://www.youtube.com/watch?v=oHg5SJYRHA0

[Hugh]

ferny wrote:

Surely this makes sense?

http://www.youtube.com/watch?v=oHg5SJYRHA0

This one I get as it was my era but I was never a fan of Rick ( well not in public c )

Colin I now after watching your clip again get what you were saying  ;)

As his lordship is a fellow Salopian I am more on his wave plusx he might have me put in the stocks ;D

Think I will put on track 11 of my new Matt Monro CD to toast my o/d victory :)

Thanks Chaps Hugh

[TimW]

908 wrote:

Have fixed the o/d problem it was the switch wires worn through causing a short circut , so repaired the wires and put extra insulation over the whole cable. Drove car and all is working perfect so I got of light  :)

I wonder who told you it was the wire in the gearstick? ;)

Glad it's fixed.  nice one

[Hugh]

339 wrote:

I wonder who told you it was the wire in the gearstick? ;)
Glad it's fixed.  nice one

Thanks mate  :)

[TimW]

908 wrote:

Thanks mate  :)

see you Monday?