View Full Version : Is it the alternator?

October 28th, 2017, 08:07
Hi, a few weeks ago my battery gauge started dropping off and then would come back up, last night on my way home from work this happened 1. Check engine light came on, 2. ten mins later battery gauge at zero, 3. 2 minutes later speedometer dead and rpm needle danced for a bit and died, 4. oil temp up to max and lights fading and windscreen wipers dying
All this tells me its the alternator but my worry is what damage have I done
Would the water pump stop working hence the high temp
I jump started it today and it starts fine but no charge, it ran for 2 minutes and the temp was again up to max
Could it be just some pulley problem
Any and all help appreciated

95 Cherokee XJ 2.5 TD

October 28th, 2017, 20:35
sounds like the alternator, high temp idk about. check your coolant, otherwise you should be fine. 2 minutes running isnt going to heat an engine up to a point that would damage it unless fluids arent present.
other than that your battery might be shot from not charging, i had to replace mine a week later and that was after having it charged up at interstate.

October 29th, 2017, 03:55
Battery out and charging, hope it takes. Gonna check coolant now. New alternator coming on Tuesday. Thank you for the help. High temp was the reason I sought help, hope it's just coolant or lack thereof
Have a great weekend

October 29th, 2017, 05:27
Check the water pump shaft and the idler pulleys.

October 29th, 2017, 07:42
Ok checked pulleys and they appear secure, Is it possible the alternator seized and stopped the waterpump working. The waterpump was replaced last December

October 29th, 2017, 07:45
Should the copper brushes move on the alternator freely without the engine running? They don't

October 29th, 2017, 09:17
Should the copper brushes move on the alternator freely without the engine running? They don't

If you're talking about the copper windings which are visible on the outside of alternator, no, they remain stationary while the armature inside the alternator which is attached to the pulley rotates. One side of the armature shaft "rides" on a set of spring-loaded brushes (basically little metal blocks with wires attached to them.) These brushes should only move towards the armature shaft under spring pressure as they wear.

October 29th, 2017, 09:25
Yes I was talking about the visible copper windings
Thank you