VTT Crank Bolt Capture install guide

[buster84]

Originally Posted by Imperial328i

I did not remove the belt from the pulley. The pulley has nothing to do with timing, so no worries there. I initially did not release belt tension, but as I backed the bolts out I noticed there was a lot of tension still applied to the pulley and it was making it hard to get the bolts out. I would get one loose enough to remove with my fingers, then move on to loosen another. When I went back to take the bolts out by hand some were tight again, as the pulley had shifted and was now pulling against that bolt.

This job is very easy from the top, just a little uncomfortable, but if you're a practiced mechanic it's no problem.

I guess the more i think about it, the pully with no bolts would just spin and wouldnt affect the hub at all and im not sure what i was thinking earlier when i said that, lol. The bigger concern would be an unaligned belt that could end up shreding or worse shreding and getting pulled into the crank hub (known problem on many bmws).

[Mintsopoulos]

Im really tempted to do this since the car will be in the air for the next week or so getting new wheels/tires. I am just a little worried about the pulley slipping/falling off.

[buster84]

Originally Posted by Mintsopoulos

Im really tempted to do this since the car will be in the air for the next week or so getting new wheels/tires. I am just a little worried about the pulley slipping/falling off.

I wouldnt be. Originally i was thinking that the belt tention could cause the pully to want to turn while the engine is off causing the hub to slip, but the more i thought about it that would be impossible since the amount of torque required for that to happen is way over the 500tq levels and doesnt seem possible from just the small amount of torque being put on the hub from the harmonic balencer.

Here is a good video showing what it looks like when you remove the harmonic balencer and how the crank hub pully is unaffected. Start at the 4min mark on the video.

[MINERALGREY_F80M3]

Originally Posted by buster84

I wouldnt be. Originally i was thinking that the belt tention could cause the pully to want to turn while the engine is off causing the hub to slip, but the more i thought about it that would be impossible since the amount of torque required for that to happen is way over the 500tq levels and doesnt seem possible from just the small amount of torque being put on the hub from the harmonic balencer.

Here is a good video showing what it looks like when you remove the harmonic balencer and how the crank hub pully is unaffected. Start at the 4min mark on the video.

Great vid!

I tried going from above as mentioned by Imperial328i but got scared of like you mentioned something falling catastrophically lol but NOW I feel confident taking your time this can be done!

[MasterYous]

Originally Posted by MINERALWHITE_F80M3

Great vid!

I tried going from above as mentioned by Imperial328i but got scared of like you mentioned something falling catastrophically lol but NOW I feel confident taking your time this can be done!

You should definitely try it. Even if your pulley comes off, you can release tension on the belt and fix it, as many DIYers here have done.

I took extra pains to make sure my pulley did not move. These extra pains are detailed in my writeup, but to summarize:
- work very slowly, use bare hands so you get a good feel inside the hub
- kitty corner approach
- loosen all bolts (kitty corner fashion) first but keep them fastened
- have someone on standby to hold the pulley if needed
- remove one bolt at a time - make sure you have loosened them enough so you can do this by hand
- immediately apply loctite to the first two new CBC bolts and insert them /carefully/ in kitty corner - hand tighten, do not torque them
- continue with other bolts also with same approach
- once all bolts are in proceed to torque to spec, in kitty corner fashion

your pulley will probably not come loose if you are super careful.

[k9lovr]

Originally Posted by Imperial328i

I did not remove the belt from the pulley. The pulley has nothing to do with timing, so no worries there. I initially did not release belt tension, but as I backed the bolts out I noticed there was a lot of tension still applied to the pulley and it was making it hard to get the bolts out. I would get one loose enough to remove with my fingers, then move on to loosen another. When I went back to take the bolts out by hand some were tight again, as the pulley had shifted and was now pulling against that bolt.

This job is very easy from the top, just a little uncomfortable, but if you're a practiced mechanic it's no problem.

If you wouldn't mind I may reach out to you when I go to install mine in a few months. Appreciate the insight since you have already done one.

[Imperial328i]

Originally Posted by k9lovr

If you wouldn't mind I may reach out to you when I go to install mine in a few months. Appreciate the insight since you have already done one.

Of course, I love talking shop with my Bimmerpost boys.

[MINERALGREY_F80M3]

+1 for doing this from above with simply removing the intake! Big thanks to OP and Imperial328i if you take your time and are good with just “feeling” things out it doable. I released the tension on the belt and had no fear the pulley would move. Hell I did this last night, alone with a flashlight and a few beers and it took me an hour and a half.

Saved $$$ by DIY and saved time thanks to Imperial328i

Cheers!

[Imperial328i]

Originally Posted by MINERALWHITE_F80M3

+1 for doing this from above with simply removing the intake! Big thanks to OP and Imperial328i if you take your time and are good with just "feeling" things out it doable. I released the tension on the belt and had no fear the pulley would move. Hell I did this last night, alone with a flashlight and a few beers and it took me an hour and a half.

Saved $$$ by DIY and saved time thanks to Imperial328i

Cheers!

Another crank bolt officially captured

[Cboy]

Originally Posted by MINERALWHITE_F80M3

+1 for doing this from above with simply removing the intake! Big thanks to OP and Imperial328i if you take your time and are good with just "feeling" things out it doable. I released the tension on the belt and had no fear the pulley would move. Hell I did this last night, alone with a flashlight and a few beers and it took me an hour and a half.

Saved $$$ by DIY and saved time thanks to Imperial328i

Cheers!

How are you torquing it down? Does a 3/8 torque wrench fit? What brand is yours?

[Imperial328i]

Originally Posted by Cboy

How are you torquing it down? Does a 3/8 torque wrench fit? What brand is yours?

I've got a cobalt 1/2" drive that goes up to like 200 or 250 foot pounds. Fit just fine.

[Cboy]

Originally Posted by Imperial328i

I've got a cobalt 1/2" drive that goes up to like 200 or 250 foot pounds. Fit just fine.

So you used a 1/2" and torqued it to 25ft lb?

[Imperial328i]

Originally Posted by Cboy

So you used a 1/2" and torqued it to 25ft lb?

Yes sir

[M2_MEDUSA]

Great write up mine goes in after my 1,200 mile break in service

[Eric SS]

I went ahead and did this yesterday. I don't have particularly large hands or forearms and there was no way that I was going to be able to do this from the top with the fans in place. I tried for about 10 minutes before i finally gave up. I consider myself to be a very proficient mechanic and do all of my own work on my cars.

So, I ended up going from the bottom. It's a lot of tedious removal of items but pretty easy. I also recommend dropping the oil cooler and cleaning out above it like OP mentions. Mine had a ton of debris and cigarette butts lodged up there. It's 3 bolts and takes literally 30 seconds to drop.

I was able to use a 6pt 8mm socket instead of an E5 reverse torx bit and it fit perfectly fine to remove the OEM CH bolts.

In regards to the belt, my hub was starting to move a little so I used a T55 bit on my 1/2 drive socket in the tensioner and lodged it under the radiator hose to remove most of the tension. That seemed to do the job. I then put in 2 bolts with the VTT CBC without Loctite to make sure it stayed in place while I threaded in the other bolts with Loctite. I then removed those and put Loctite on them and put everything back together.

Thanks to OP for a good writeup.

[marauder1]

So I did this install method. Took me 2-3 hours as I really took my time with tightening the bolts back up to do it evenly. Barely need to remove anything and there's plenty of space.

[Twistm4]

Just go to hardware store and get some studs that will fit and as you loosen one bolt or two put 3 studs in the holes. Slip CBC over the stud holes, put a couple bolts back in then take the studs out.

Super easy and makes sure pulley wont move.

[icegrill]

Originally Posted by Twistm4

Just go to hardware store and get some studs that will fit and as you loosen one bolt or two put 3 studs in the holes. Slip CBC over the stud holes, put a couple bolts back in then take the studs out.

Super easy and makes sure pulley wont move.

Awesome idea!

[Bluer2]

Originally Posted by buster84

I wouldnt be. Originally i was thinking that the belt tention could cause the pully to want to turn while the engine is off causing the hub to slip, but the more i thought about it that would be impossible since the amount of torque required for that to happen is way over the 500tq levels and doesnt seem possible from just the small amount of torque being put on the hub from the harmonic balencer.

Here is a good video showing what it looks like when you remove the harmonic balencer and how the crank hub pully is unaffected. Start at the 4min mark on the video.

would it be a good idea to install the crank seal guard at the same time as the crank bolt capture? would you recommend the crank seal guard?

[F80RN]

Subbed for later reference.

[marauder1]

It's not terrible if it slips. You remove the carbon brace, and front intake. Then using a T50 rotate the tensioner out of the way and use an allen key or something to hold it in place. Do your install then release the pin in the tensioner.

[Twistm4]

I just did this job last night for a friend. We noticed the VTT CBC wouldn't slip over the bolt. It wasn't even close. We ended up having to file a bit off two sides to get it to go on. Just a heads up if it doesn't fit try filing it a bit.