question Zetor 7211 not charging

I replaced the external regulator a year ago when it failed. New battery 2 months ago. Battery seemed to be getting weak so I check charging. Not charging so I replaced the alternator last week. Still not charging. When I insert the key the battery light doesn't come on. checked that, and I have power on both sides of the bulb (one side is weaker than the other) like the tractor was running. defective alternator or regulator. any thoughts?

Hello Kevin,

actually it's like a good neighborhood here - if you're new, you first introduce yourself (or your technology/tractor) briefly in words and pictures before jumping straight into a technical question.


As for your question - if we had photos, we would know whether you installed an alternator with an integrated regulator or the classic one with a separate regulator.

You say you measured the charging voltage - how high was it, i.e. how many V?
Is the ground cable, the ground connection to the alternator and battery really OK?
What battery size (Ah) and type (AGM or normal) did you install?

The bulb must work to charge. Check the bulb on a battery carefully, they fail often and get bad connections. 12 volts on one wire, the other wire earths through the alternator until the engine is started.