speed and tach work intermittently

[jdands]

I have a 99 seaswirl w/ 4.3 volvo penta. The speedometer works and then doesn't and the tach reads right and then wrong and then right again?

 

[MI_Thumb_2010]

Re: speed and tach work intermittently

Loose Ground Wire??

 

[big_b]

Re: speed and tach work intermittently

I would say lose ground/signal wire or even low voltage from battery/alternator.

Even a volt or two low can make some tachs read way off ...

CHeck wires and the charging system

 

[jdands]

Re: speed and tach work intermittently

Thanks much, will get back w/ results

 

[Silvertip]

Re: speed and tach work intermittently

The speedo is not electric so the issue with that is there is debris in the pitot or kink in the pressure tube that needs attention.