6 replies to this topic

[kiwi-lilj]

Hi all,

 

My speedometer has been playing up for a while and now finally failed me on a WOF check today. It first would come up as you accelerated alright but when you slowed down it was very slow to return. Now when you go for a drive it comes up to about 40mph and then gets stuck there for the duration of the drive, once it’s parked up it does slowly return to 0mph.

 

The odometer appears to still be working so I don’t think it’s the cable, anyone have any clues?

 

 Thanks 

 

 

[Bruiser]

Hiya Blair, not a torana, but probably similar..
My commodore speedo was acting the dick for a while, being jerky. Just sticky, obviously.
So I pulled it out to un-stick it and ended up buggering the clock spring and even the needle itself.
If you have a crack at it yourself, watch out
They are super delicate bastards and my carefullest obviously wasn’t careful enough
Mine goes to the instrument specialist next time

[sibhs]

Hi Blair, my speedo used to jump around so I changed cable, it was better but still not perfect. When I got the speedo serviced it was so much better.

 

Marty

[shadey1963]

Could be the grease /lubricant going hard? Happened on a Torana I had, cleaned it regreased and all good.

[kiwi-lilj]

Thanks for the replies,

 

 I remembered that I had GTR cluster stored away so I pulled the speedometer out and slipped it into my cluster. I thought this is good, fix the speedometer and the car will actually go faster seeing how this one goes up to 120MPH. So I took it for a test drive, the speedometer started working initially but then started dancing around quite violently, but that was short lived as it suddenly dropped down to zero. While I can’t be certain because the speedometer didn’t work I don’t think the car had become any faster either.

 

So I pulled the cluster out again and the cable, the cable had broken down the gearbox end. The broken cable had only done about 500 miles so something funny happened.

 

So I sent my original speedometer off to an instrument specialist and ordered another new cable, jammed it all back in there and it works like it’s brand new. So happy days LIL J is back out there struggling to keep up with the traffic.

[sibhs]

Good result Blair. Thanks for update.

 

Marty

[RallyRed]

No expert at all, but -

I think the old school speedos in Toranas work by the gearbox spinning the cable.

So -

The spinning cable a the dash end, rotates and causes an eddy current/magnetic field type thingo, that produces a torque and acts on the actual speedo mechanism, to make it rotate  ( against a fixed spring?) so that it goes up to the correct reading.

My limited understanding would then be  -

1 Jerky operation , probably cable.

2 Sticky operation, probably within the speedo itself.

 

Happy to be wrong.