870 Tachometer Problem

[JD5210]

My neighbor asked me to take a look at the tachometer on his 870. At idle the tachometer just about pegs itself and bounces around at the 3,000 RPM mark increasing the tractor RPMs just moves it closer to being pegged. While I did not remove the cable it looked good. There is a squealing noise, sounds more like it is coming from the tachometer.

Thought I would do some research before taking things apart. Looking at JDparts the cluster does not appear to be a sealed unit.

Has anyone had this experience with the tachometer on a 870/970/1070? Does anyone know what it looks like inside the cluster does the tachometer have gears or something else? Is if far to say it is not electronic?

Thanks in advance for any help.

 

[ndgregor]

My neighbor asked me to take a look at the tachometer on his 870. At idle the tachometer just about pegs itself and bounces around at the 3,000 RPM mark increasing the tractor RPMs just moves it closer to being pegged. While I did not remove the cable it looked good. There is a squealing noise, sounds more like it is coming from the tachometer.

Thought I would do some research before taking things apart. Looking at JDparts the cluster does not appear to be a sealed unit.

Has anyone had this experience with the tachometer on a 870/970/1070? Does anyone know what it looks like inside the cluster does the tachometer have gears or something else? Is if far to say it is not electronic?

Thanks in advance for any help.

Did you ever dig into this tachometer? I am having a similar issue on a John Deere 1070 and am debating taking the instrument cluster out and seeing what all is wrong. Is it difficult to do?

Thanks for the help,
Nick

 

[JD5210]

Must I admit did not believe it nor would I have believed if I had not seen it, but once it warmed up outside it started to work ok.

Sorry I can not be more helpful.