Why use a method that you can't torque the VANOS hub bolts to spec?

[sapote]

This method allows using a normal torque wrench on the hub bolts:

Condition: Crank at TDC compression stroke on the last CW rotation, cams are timed by bridge pin, VANOS removed with solenoid plate loosen or removed from it.

1) turn the hub full CW
2) insert spline shaft to the hub by turning the shaft no more than 1 tooth CCW as needed, and only insert to 1/4 or 1/3 deep. Torque 2 opposite bolts to 10 Nm then back out 1/4 turns, leave all other bolts threaded but loose.
3) Use the 2 long top bolts to hold the vanos with a used gasket (loosen or remove the solenoid plate already) to the head, then reach in and connect the pistons to the spline shafts using the left-hand-threaded connectors.
4) evenly torque down all the vanos to head bolts to spec taking care not to cock the vanos to prevent jamming the pistons in their cylinders.
5) Check cams timing with bridge pin. If good goto step next step. If out of timing then the hub bolts are too tight in step (2) causing hub not able to rotate against sprocket and ended up turning the cam instead, then repeat from step (1).
6) reach in and torque as many hub bolts as possible by open end wrench to snug.
7) remove all vanos to head bolts, then try to pull it forward and disconnect the left-hand-threaded connector. Remove vanos off.
8) replace with new gasket (I reused the same old gasket and it's OK), torque down all hub bolt to spec 14 Nm with torque wrench
9) install vanos per step (3 and 4) above.
10) Rotate crank 4 turns, stop at TDC on CW rotation. Check cam timing with bridge pin. If good then finish up other parts.

You should have no fear running the engine after this, as all the bolted were torqued to spec. The crowfoot tool is not as accurate since the bolt is off center from the torque wrench.

[Cubieman]

Thanks for taking the time to post this.

[r4dr]

If I remember the Beisan procedure right, you can get to the top bolt or two with a regular torque wrench, no problem. I torqued those to the spec, then felt how snug this was with an box wrench, and did the hidden ones based on that. Figured it was good enough.

[Cubieman]

If I remember the Beisan procedure right, you can get to the top bolt or two with a regular torque wrench, no problem. I torqued those to the spec, then felt how snug this was with an box wrench, and did the hidden ones based on that. Figured it was good enough.

On the intake side you can get a torque wrench on the upper most bolts during Beisan procedure. I am going to give this alternative method a try, now its just a matter of trusting my CDI torque wrench. I really need to just buy a techangle.

[sapote]

If I remember the Beisan procedure right, you can get to the top bolt or two with a regular torque wrench, no problem. I torqued those to the spec, then felt how snug this was with an box wrench, and did the hidden ones based on that. Figured it was good enough.

With the Vanos installed, do you really have enough room for using a torque wrench and socket? The torque reading maybe off if the socket and drive are not in line with the bolts.

[r4dr]

With the Vanos installed, do you really have enough room for using a torque wrench and socket? The torque reading maybe off if the socket and drive are not in line with the bolts.

It's been a while, but unless we're talking about different bolts (and we could be), I think Beisan has you tighten them, then back them off slightly. Then the VANOS gets reinstalled (covering the hub) and the bolts are tightened down for good. So when the VANOS was off, I torqued them to spec, felt them with the box wrench, then slightly loosened them to reinstall. Tightened them back by hand after the VANOS was back on.

[sapote]

It's been a while, but unless we're talking about different bolts (and we could be), I think Beisan has you tighten them, then back them off slightly. Then the VANOS gets reinstalled (covering the hub) and the bolts are tightened down for good. So when the VANOS was off, I torqued them to spec, felt them with the box wrench, then slightly loosened them to reinstall. Tightened them back by hand after the VANOS was back on.

This pic shows the said 6 hub bolts to be torqued to spec after VANOS installed to the head. You don't have enough room to torque the EX hub bolts with a standard torque wrench, and using crowfoot is not accurate because the bolt is off center from the torque wrench drive. I suggest to to torque these bolts to spec with the VANOS removed.

[heinzboehmer]

This pic shows the said 6 hub bolts to be torqued to spec after VANOS installed to the head. You don't have enough room to torque the EX hub bolts with a standard torque wrench, and using crowfoot is not accurate because the bolt is off center from the torque wrench drive. I suggest to to torque these bolts to spec with the VANOS removed.

Crowfoot wrenches are fine and shouldn't be any less accurate than a standard socket, as long as you do the math for the change in geometry and set your torque wrench appropriately. But agreed, taking the VANOS off does allow you to torque the bolts in a more straight forward way.

[sapote]

I edited the first post to include the torque spec for the hub bolts during pretension the hub (10Nm then back out 1/4 turns) and the final torque 14 Nm to all hub bolts.

[Cubieman]

So per beisan the left/right hub bolts are tightened and backed off 1/4th turn while the top two vanos/head mounting bolts are only hand tight, then the vanos is pressed fully onto the head, bottom 3 vanos/head bolts are installed and torqued as well as the top 2 vanos/head bolts that were just previously hand tight are torqued.

After this the remaining hubs bolts are tightened by hand to 10.5ft lb.

Per your procedure the splined shafts are only installed 1/4 to 1/3 of the way into the hubs and the left/right hub bolts are tightened/backed out 1/4 turn. Isn't that different from Beisan in that when tightening the left/right hub bolts (per Beisan) the vanos/head top mounting bolts are threaded in hand tight thus I would *think* the splined shafts would be further than 1/4th to 1/3rd of the way into the hubs.

I guess I am just pointing out that your procedure MAY have the splined shafts sticking out of the hubs further vs. Beisan.

I may be wrong here and am not saying anything is wrong with your procedure at all(yours is closer to TIS than Beisan) but I just wanted to ask about that.

[Slideways]

Using a crowsfoot wrench is what is recommended on the TIS and the torque before backing off a 1/4 turn is 14nm. The final torque is also 14nm.

I would not deviate from the Beisan or TIS instructions.

[sapote]

...I guess I am just pointing out that your procedure MAY have the splined shafts sticking out of the hubs further vs. Beisan.

More is better. Seriously it's not matter so much as long as the the spline shafts are not bottomed out on the hub when the vanos is not bottomed out on the head. Give them a gap of 3mm minimum should be enough.

[sapote]

Using a crowsfoot wrench is what is recommended on the TIS and the torque before backing off a 1/4 turn is 14nm. The final torque is also 14nm.

I would not deviate from the Beisan or TIS instructions.

1) Tool 117200 is not a crowfoot adapter. It's an accurate digital torque wrench. BMW would not recomment to torque anything this critical using a crowfoot adapter with torque wrench.
2) Beisan instruction says to torque these hub bolts to spec by feel, not using any torque wrench at all. Still think it is a precise method?
3) I just visited TIS site and here is the pic of the pretension torque spec on the bolts: 10 Nm and not 14 Nm then back out 1/4 turns. Where did you get your Tis instruction?

4) We don't have tool 117200 as Tis instruction called for, nor have other tools with compress air to move the pistons as instructed; therefore deviate from Tis instructions and develop a method for DIY is not a bad thing. Why Tis doesn't use a standard torque wrench with 10mm socket -- as in my method -- to torque the hub bolts? Because time is money and the factory didn't want to spend the times to remove the vanos off the head again to have room for using a standard torque wrench with 10mm socket on the hub bolts and swap out the used gasket. We have plenty of times for our cars.

[sapote]

So per beisan the left/right hub bolts are tightened and backed off 1/4th turn while the top two vanos/head mounting bolts are only hand tight, then the vanos is pressed fully onto the head, bottom 3 vanos/head bolts are installed and torqued as well as the top 2 vanos/head bolts that were just previously hand tight are torqued.

Maybe this is the reason why your timing failed:
1) did you torque the left/right bolts to spec then back out 1/4 turns, or just tightened by feel?
2) after the top 2 vanos bolts are hand tight, was there more than 5mm gap between vanos and head? If not enough gap then the result timing could fail.

[Slideways]

1) Tool 117200 is not a crowfoot adapter. It's an accurate digital torque wrench. BMW would not recomment to torque anything this critical using a crowfoot adapter with torque wrench.
2) Beisan instruction says to torque these hub bolts to spec by feel, not using any torque wrench at all. Still think it is a precise method?
3) I just visited TIS site and here is the pic of the pretension torque spec on the bolts: 10 Nm and not 14 Nm then back out 1/4 turns. Where did you get your Tis instruction?

4) We don't have tool 117200 as Tis instruction called for, nor have other tools with compress air to move the pistons as instructed; therefore deviate from Tis instructions and develop a method for DIY is not a bad thing. Why Tis doesn't use a standard torque wrench with 10mm socket -- as in my method -- to torque the hub bolts? Because time is money and the factory didn't want to spend the times to remove the vanos off the head again to have room for using a standard torque wrench with 10mm socket on the hub bolts and swap out the used gasket. We have plenty of times for our cars.

Certainly looks like a crowsfoot attachment. newTIS.info