Mahindra Alternator / Rev counter

[DaveB275]

Just had to replace the alternator, but now the new one is fitted, the rev counter doesn't work until very high revs, when it just moves off zero.

Have I done something stupid when fitting, or is this a sign of anything in particular?

Tractor is a Mahindra FS2542EUR. Not that common here in UK, and there are no dealers / limited parts backup.

Appreciate any advise.

 

[JerryK]

Just a wild guess, but either the new alternator is not good.... or, just the wrong alternator. Extreme belt slipping would do it, too... but you would notice that it was not charging and probably see smoke and/or hear it. Good luck, Jerry.....

 

[dickfoster]

Just had to replace the alternator, but now the new one is fitted, the rev counter doesn't work until very high revs, when it just moves off zero.

Have I done something stupid when fitting, or is this a sign of anything in particular?

Tractor is a Mahindra FS2542EUR. Not that common here in UK, and there are no dealers / limited parts backup.

Appreciate any advise.

What is the voltage at idle and at high RPM? That's where I'd start.

 

[DaveB275]

Thanks for replies. Voltage shows about 14.5V on idle, and pushing 16V at higher revs.

Have emailed the alternator supplier, but no response.

 

[dickfoster]

NO NO NO NO. 16V is not good at any RPMs. Stop and correct before you burn out some expensive electronics. You only need 14 something even at high RPMs. 16 volts will destroy the battery at least in very short order. Something is haywire with voltage regulator in the new alternator. DO NOT RUN the engine until this has been corrected.