5.9 altenator question

[Stuntmanmitch]

I can't find a thread addressing this, especially on my phone but...

Tc2000 5.9 160 amp leece Neville altenator died, replaced with a Wilson but the tach wasn't working. I took it off and moved the wire to match how it looked on the previous altenator but now the batteries aren't getting any juice.

I read a thread where someone cut a wire on the back of the altenator to solve this but I'm not trying to do I can't undo

Getting a jump to get to my overnight spot, I try to upload pics of both altenators tomorrow

[Stuntmanmitch]

Upon further review, after starting with a boost shortly in to my drive the tach was working. Maybe the batteries didn't get enough juice last night or worse are no good now? Voltage was really low before I could replace the old unit.

[Booyah45828]

Did you not charge the batteries after replacing the alternator? Alternators really aren't designed to charge up dead batteries. Doing so can hurt both the alternator and batteries.

They're meant to charge back up the little bit of power used for startup, and supply the power demands while the engine is running.

Some alternators don't create power at idle either. You have to either be rev'd up, or driving for them to work, maybe that's your issue as well.

[Stuntmanmitch]

I had them on a charger for a few hours. I drove 20-30 mins today and yesterday. I don't think they are holding a charge. Seems they don't have enough cold crank amps. I'm probably going to pick some up tomorrow.

[Stuntmanmitch]

Tensioner needed replacing too, had to work today, will see if that was the issue with the batteries. Today was the first time I felt comfortable driving normal and not nursing the bad tensioner. Not looking forward to 2*200$ for batteries but whatever.

[Native]

Check around, you should be able to get a group 31 battery for under $100.00.

[Stuntmanmitch]

Bad battery or batteries. Replaced both today. Stayed with 8d 10$ more for 1425cca. (390$ total after core).