any DIYs on replacing the alternator on an 08 E70 with 4.8i

[gregg3gs]

Haha... I've experianced the same "Awesome" when I replaced mine.

Think this way: when some alternators fail they reduce the amount of current and voltage produced. Its the spark, generated by voltage and amperage that drived the ignition. This is also a reason why some people put a bigger alternator to replace their small units.

Just saying.

[MW3Designs]

I am about to embark on a alternator replacement in my 4.8, came across this post searching, but am unable to find any other good diy info.

[Nanniepoo]

Bumping as I'm looking for torque specs for the install.

N62 with 220 amp alt.

[Bmwfvr]

This has the tightening torques

https://www.newtis.info/tisv2/a/en/e...-parts/GUMKp5R

Sent from my SM-G955U using Xoutpost.com mobile app

[Nanniepoo]

Originally Posted by Bmwfvr

This has the tightening torques

https://www.newtis.info/tisv2/a/en/e...-parts/GUMKp5R

Sent from my SM-G955U using Xoutpost.com mobile app

Is the idler pulley really 80 Nm? That seems really high

[Nanniepoo]

Originally Posted by Bmwfvr

This has the tightening torques

https://www.newtis.info/tisv2/a/en/e...-parts/GUMKp5R

Sent from my SM-G955U using Xoutpost.com mobile app

Re reading that and that might be for the alternator pulley.

There's conflicting info everywhere. Even TIS conflicts itself for the tensioner.

42 Nm here: https://www.newtis.info/tisv2/a/en/e...lement/5w2memI

And 22 Nm here: https://www.newtis.info/tisv2/a/en/e...ent/1VnYumS8Y8

That first link says 90Nm for idler.

[rbryantaz]

Originally Posted by Nanniepoo

Re reading that and that might be for the alternator pulley.

There's conflicting info everywhere. Even TIS conflicts itself for the tensioner.

42 Nm here: https://www.newtis.info/tisv2/a/en/e...lement/5w2memI

And 22 Nm here: https://www.newtis.info/tisv2/a/en/e...ent/1VnYumS8Y8

That first link says 90Nm for idler.

Torques should be based on the bolt grade and size and if it is dry or lubricated...


I sell replacement INA pulleys Tensioner pulleys for the 4.8i and recomend the following:
The new Alt/WP/PS pulley is torqued to 40ft*lbs (55N*m) dry for the M10 bolt (which is actually conservative). 42Nm should be tight enough but 22 seems too loose... If it was supposed to be 22 then they would have used an M8 bolt like the AC tensioner.

https://www.boltdepot.com/fastener-i...ed-Torque.aspx

The alternator on the 4.8i actually isn't a bad job once you remove the belt and the fan. I did one in a couple of hours a few weeks back when diagnosing a sweak. Sadly it was the stupid HT pulley from ECS that was manufactured with the incorrect offset. I don't recommend that part!

As a result I now have a low mileage (5k miles) Valeo 180amp alternator that I need to sell now if anyone needs one...

-Rich

[Nanniepoo]

Yeah I finished pretty early yesterday. It really wasn't too bad