My (wife's) 2009 xdrive35d

[robnitro]

I don't believe it's pressed on.

I'm doing mine next week.
E12 torx iirc, 40Nm and then 120degrees according to rheingold.
There's a window under the car to hold the flywheel some how.
There's another point near the starter but seems like a pita to get to.

[sgrice]

Interesting that back on post #58 daytonatrbo said: "Today, it threw a charging error while driving and EVERYTHING threw an error a moment later. The steering got stiff, the OBC threw an error for high engine temp, then one for dynamic control."

In hindsight, the steering issue was a tipoff to check the harmonic pulley. This link gives a discusssion/view of the issue.

Good luck with the repair. It would be great if you could document the steps/challenges to the repair. I suspect that many of us will have to deal with this is as our cars age.

[daytonatrbo]

In hindsight, it was a huge indicator.

At the time, I assumed that the other issues were due to the severe low voltage.

On the e38, the servotronic steering goes haywire with low battery voltage, and the 5Vref that all of the sensor run on can rapidly degrade. It seemed entirely possible to me that the issues were all battery voltage related.


Obviously that was a poor assumption.

I've also never had a harmonic failure, even on 30 year old vehicles, so it wasn't even on my radar.

[robnitro]

What makes these cars a pain is that battery control module. On a normal car you can tell that the alternator is working just by measuring voltage at idle with everything switched off and then lights heater defroster fan on. A huge drop gives it away. But in your case, the balancer was on the edge of failing, surprised it didn't just flat out fail! That's why on e90post the trend has been to replace it preventatively, because it also drives the water pump, but still better than the tdis with water pumps driven by the timing belt!

[daytonatrbo]

Yeah, I think it's been failing a while. Not long before I bought the car, the battery and starter were replaced, leading me to believe they may have been chasing a weak electrical issue. Too bad they replaced the battery with the wrong size and it's not an AGM, so I'll have to replace it soon too.

Fortunately the pulley ultimately failed while I was just driving around the block.

When I got to work on the car, I found chunks of rubber in the plastic belly pan. It still took a while to dawn on me what I was looking at.

[robnitro]

You are fine with the non agm. I've been using a group 65 battery since last year without issues. Only time I had a problem it was because my Bluetooth obd adapter wasn't going into sleep mode, giving the battery drain message. When my injector 5, 6 were going bad, the battery had no problem with multiple cranks... As usual the bmw software complained but it still cranked fast.

On diesels, what matters most is AH capacity, or Reserve minutes. My battery has 150rc which roughly translates to 88ah. The autozone h8 agm battery is 160rc with 95ah

If you are worried, code the battery size and type using ista/p, Carly, or ncsexpert

[daytonatrbo]

The discount brand battery that currently resides in mine is only rated 70Ah

___________________________


The last decision I need to make is whether I want to keep the cheapo reman alt (which actually seems like a really well done reman, for only about $120) ordrop my OEM alternator back in and return the reman.

I'm tempted to keep the reman and rebuild my OEM alternator myself and put it back in down the road

[daytonatrbo]

Originally Posted by sgrice

Good luck with the repair. It would be great if you could document the steps/challenges to the repair. I suspect that many of us will have to deal with this is as our cars age.

Removing the pulley ended up being a breeze. I just completed that part. And now I'm thinking I should have ordered the 4 bolts, even though they look very hard and not like the typical torque to yield stuff. I may check with my local dealer and at least give them that business.



I raised the vehicle and dropped the plastic shield under the transmission. I already had the forward shield out, and I already had the cooling fan and AC belt off. I popped the accessory belt back off.

I used a small piece of soft wood on top of a small bottle jack into the inspection window on the bottom of the bell housing.





With just a very small amount of pressure, the wood block provided all the holding required to remove the 4 bolts. They were not so tight you couldn't take them loose with a standard 3/8" ratchet and an E12 torx type socket.




The pulley is a bit heavy, and you need to hold it before you remove the last bolt, as it would fall right off the front of the crank.

You can see here, it has utterly and completely failed. I could turn the pulley by hand while holding the center.




And here's the missing bit of rubber!




Also, I had planned on replacing both belts (I really need to do the idler/tensioner pulley too) so I had picked up this Lisle Stretch Belt remover off Amazon, and I made a tool for a 1/2" drive socket that keys into the cross snap inside the crank pulley to rotate the pulley as needed for the lisle tool. You flip the tool over to install the belt.


I think it will work fine once the pulley isn't slipping
_____________________________

Just found the online TIS thread and found this:

11 23 Vibration damper (SCR) 1AZ Harmonic balancer to crankshaft
Tightening Torques
Type Thread Tightening specifications Torque

M57T2 / TOP M10x86 12.9 Replace bolts
1. Jointing torque 40 Nm
2. Angle of rotation 120 °

[robnitro]

At 40Nm+120 degrees I doubt they are TTY, but I did order 4. Which dampener did you go with?

70Ah should be fine in your climate especially if you don't do a lot of short trips. Some guy near me had a TDI with a cheapo honda grp 35 battery without problems. They're 1.9L but 20:1 instead of our 16.5:1 compression!

AGM doesn't offer too many benefits over a good quality flooded battery either. They're more sensitive to heat but since our batteries are roasting under the hood, BMW fit them for a longer service life. I still have my old agm and you can pop the caps and add a bit of water if you want to try to revive it. Even then, it's probably fine as it is because you had a charger issue.

[daytonatrbo]

I would tend to agree about the bolts. Even after spending $7 a piece on them, I'd rather had the peace of mind that the pulley won't decide to fly off because of my cheapness.

I ordered the febi from ECS, I decided not to use FCP, as lately they have been having a lot of shipping issues when it comes to my orders.


We do get the odd week of -20°F weather every once in a while.

But short trips aren't even possible where we live. Most of our destinations are about an hour away. Even the grocery store.