Bouncing Speedometer

[maston]

Hi All,
A bouncing speedometer, is the problem likely to be a worn/duff cable or could it also be an earthing problem at the back of the speedometer ?
Also where can I get a new one for my 390, easy to fit ?
Many Thanks

[wooly350i]

Me too, it's probably the cable or even a tooth missing off the gearbox end although I stand to be corrected, it's worse up to about 30mph but it doesn't stop the car going so it hasn't been a priority but I will read with interest.

[RCK974X]

Seen this a few times, and can be the speedo cable is 'gunked up' with old grease etc, so is sticky and doesn't turn evenly. May be worth taking out of car, removing inner cable and washing out with petrol/solvent, and then a bit of WD40 or equiv for reassembly. DON'T regrease cable (that's what I've been told anyway)

[adam quantrill]

If you do this then pull out the worm gear from the box too in case it is worn, while you are there.

If it's knackered then you will need the same colour drive.

[Jack Valiant]

Totally agree with the above had this issue with mine couple of years ago, took it out good clean and lub job done

Ian you have seen mine fella …. apart from when you were in the back of the seat as we were pulling away in the Gredge!

Chris

[smash]

Never mine the bouncing - mine shows 80 when the GPS tells me 100!

It's about as useful as the petrol gauge, lol!

[mk2 24v]

If you don't find any kinks in the speedo cable and do take it out to clean up as suggested, 3in1 oil is meant to be very good for the cables I'm led to believe

Or even just a dash of gearbox oil even

[maston]

smash said:

It's about as useful as the petrol gauge, lol!

Is that supposed to work then ??? , thought it was just for show

Thanks for all the replies everyone

[Wedg1e]

My old speedo cable had a kink in it where someone had cable-tied it to a chassis rail to keep it away from the exhaust. The speedo used to flutter slightly, it doesn't do so with the new cable I had made for the cruise control transducer.

[GOG440]

maston said:

Is that supposed to work then ??? , thought it was just for show

Thanks for all the replies everyone

I can make mine go from empty to full just by putting the handbrake on!
I think my mate the auto electrician has some work to do lol