rev counter probs

[StevenJMorgan]

The rev counter on the standard instrument panel to my volvo 2030 is giving me probs.

When the engine is started the needle flickers then goes all the way over to maximum revs and stays there until the engine is turned off when it swings all the way back to the normal engine off position.

I am useless with electrickery but have removed and cleaned all connections from the back of the rev counter and from the back of the alternator where I 'think' the rev counter gets its readings from, but have had no joy!

any pointers??

 

[noswellplease]

Wish I could help as problem seems to be badly affecting your sleep patern....someone here is bound to come up with an answer for you

 

[VicS]

[ QUOTE ]
seems to be badly affecting your sleep patern

[/ QUOTE ] You should check the posters location before making comments like that. It may have been a touch early in the morning here but not in UAE.

 

[nicks]

Sometimes removing the rev counter and putting it in the airing cupboard for a couple of weeks usually works. I know this works if the digital display doesn't work. Failing that the rev counter gets its signal from the alternator, usually just one terminal.

 

[Billjratt]

The revcounter "reads" the frequency of the raw AC the alt produces. Did you change anything before it went bad ( pulley? try to think of everything that has hapened since it was last working properly). Does the alternator charge OK? (the same as it was before the probblem) . Is it intermittant or predictable.The rev counter will also have a voltage feed which you should verify as being 12 - 14.8 volts. Are the other instruments reading correctly? What does it read if the alt sense wire(s) are disconnected? If you switch on ign without starting the engine and waggle the cable looms does anything change?