speedometer reading incorrectly

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welshy
Posts: 34
Joined: 02 Mar 2004, 23:05
Location: United Kingdom
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speedometer reading incorrectly

Post by welshy »

Hello everyone,
A few weeks ago i had the speedo cable upper section changed in my Citroen zx td as i was having a matrix changed at the time and thought it was a good opp while the dash was out. Today i had the lower cable changed, but i noticed now, that on the speedometer on the dash, that the needle now sits well below the "0" miles reading, and as a matter of fact while i am doing 40mph, the speedo only reads 20 or there abouts. It wasnt a garage that did the job, but a mate.
Could someone please tell me whats envolved in getting the speedo neddle indicator to sit exactly at the zero setting, or in laymans terms,"how do i get the needle moved up"
cheers
tom
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AndersDK
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Post by AndersDK »

Tom -
A good rule of thumb is always investigating your latest "path" of work route.
It sounds to me as the cable has not engaged correctly in the gearbox end - as here the last work was done. But could also be on the rear of the instrument - possibly pressing in the drive dog - and slipping.
Or the opposite : barely catches the drive dog.
The speedo does not suddenly reads incorrectly - it will either indicate as usual - or completely fail. But cable problems may cause all kinds of niggles.
prm
Posts: 77
Joined: 21 Jul 2004, 06:43
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Post by prm »

Tom
As Anders has pointed out -- Speedos usually work or not.
Sounds like new cables could be possibly pressing against head unit. Check that drives enter gearbox and head unit as per original. There should be a slight end float on both sections when installed.
Are new cables the same length as old units and free from oil contamination??. Also, internal core right way round.
One point-- forgive me for mentioning it.
You weren't trying to alter mileage readings.
R
Peter
welshy
Posts: 34
Joined: 02 Mar 2004, 23:05
Location: United Kingdom
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Post by welshy »

Thanks guys,
and no, i wasnt trying to alter mileage readings, i wouldnt no were to start. The speedo was never really right since i got the car, it was always flickering rapidlay when driving and not giving a clear indication of speed, and this, i was told was due to wear and tear on the cables. When the new upper part was fitted, it was never connected back to the older part because it looked kinda worn at the time and i didnt want to chance it messing up the new cable, and there was no way i was takin the dash out again, so i will never really no if it would have worked !, So were would you look to fix the problem first ?
prm
Posts: 77
Joined: 21 Jul 2004, 06:43
Location: United Kingdom
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Post by prm »

No offence Tom
Have had to rectify problems with reversed speedos. Very similar fault.
You seem to be afflicted with the old BX problem -- flickering
speedo.
Separate the two sections and apply 3-in-1 type oil to the lower section inner core.- about half a tea spoon. Hold second section vertical, 3-4 drops and allow to drain through.
The flickering is usually due to any sharp turns on the cable, especially at the head unit. Sometimes reduces as speed increases. If you can obtain gradual turns and a reasonable straight exit from head, may reduce the problem.
Check that the new upper section inner hasn't drifted out from head unit whilst unconnected.
Peter
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