Speedo sticking around 50mph

[Gapples]

Hi
Another speedo issue has raised its ugly head, its been working fine for over a year, once I started to use the car on a regular basis.
Yesterday though for whatever reason it decided to start sticking around 50mph.
I thought I was going a bit faster than 50mph on a dual carriageway so kept accelerating then suddenly the speedo jumped to 75mph.
Anyway it continues to stick at 50, even slowing down it will stick at 50 until down to about 25 to 30 and it will suddenly drop to the correct speed.
I can only think it's the speedo itself causing this, thought and advice welcome ?

[jimmi480]

Hi .
never herd of this before. interesting to hear about this. god luck man.

[dragonflyjewels]

Needle catching on peeling face perhaps ?

[dcwalker]

First suspect is needle catching on peeling face.

If the speedo face is in good condition with nothing for needle to catch on, I'd suggest that one of the two tiny clock springs behind the needle has broken - what you describe are some of the classic symptoms of that; it's an issue on one I'm repairing at the moment for a friend...

David

[Gapples]

Yes, my only thought was the needle catching the peeling face as that's just about right where the 50 mph is.

[brinkie]

Definitely the needle catching on something. The speedometer is driven by a PWM signal, which doesn't suddenly stop and jump. Peeling of the speedo face is very common and unfortunately I don't have any faces in miles left (tons of them in km of course), so your best bet is sourcing a non-peeling UK speedo and swap the faces. The very early (up to MY 1989) and the late ones (MY 1993/1994) usually don't peel, MY 1990-1992 usually do. Also the rev counter faces are peeling from those years, but revs don't come in either metric or imperial units so I have plenty of those
As a temporary measure, you could take the instrument cluster out, take the front off and blow the debris off with pressurised air, so the needle will run freely again.

[WRDendy]

There' also Murf's blue gauge faces available to download and print on the main site, at the bottom under 'Volvo 480 Fun Files': http://www.volvo-480-europe.org/volvo480/downloads.php

[WillC9303]

The very early (up to MY 1989) and the late ones (MY 1993/1994) usually don't peel

My 1993 MY cluster has started to started to peel around the odometer area, but it’s relatively mild compared to some I’ve seen.

[Gapples]

Definitely the needle catching on something. The speedometer is driven by a PWM signal, which doesn't suddenly stop and jump. Peeling of the speedo face is very common and unfortunately I don't have any faces in miles left (tons of them in km of course), so your best bet is sourcing a non-peeling UK speedo and swap the faces. The very early (up to MY 1989) and the late ones (MY 1993/1994) usually don't peel, MY 1990-1992 usually do. Also the rev counter faces are peeling from those years, but revs don't come in either metric or imperial units so I have plenty of those
As a temporary measure, you could take the instrument cluster out, take the front off and blow the debris off with pressurised air, so the needle will run freely again.

Thank you very much, my 480 is a 1992 1.7 es LE.
I didn't really mind the peeling, well until now, I rather thought it could be causing the problem.
Not to worry its fixable, one way or the other. What sort of job am I looking at to take this unit out ?

I'll keep a look out for a uk speedo face, thanks again for the information

[dcwalker]

May well be able to help you with a speedo face - let me check....

David

[Gapples]

May well be able to help you with a speedo face - let me check....

David

Thank you David, any help greatly appreciated

[dcwalker]

May well be able to help you with a speedo face - let me check....

David

Thank you David, any help greatly appreciated

I'll check when I'm back home this evening...

David

[dcwalker]

I do have a spare speedo face It's one which had a very small amount of peel which I have trimmed back flush and then black painted. You'd be hard pushed to tell once it's back behind the cluster clear plastic...

It's yours if you'd like it and you PM me your address.

David

[Gapples]

Thank you David, PM sent

[dcwalker]

Thank you David, PM sent

And replied