Problem with VANOS Torx Bolt

[Matt865]

Greetings, everyone. I haven't commented in a while since I usually rely on the internet for guidance. However, I am now facing a challenge and need assistance.

I have refurbished the twin VANOS system of my M54 525i. None was a pleasant task that let me to use my new ultrasonic bath.

Nevertheless, I am now experiencing difficulties with the left-handed T30 bolt that links the VANOS to the cranks after reattaching the VANOS.

The protocol I followed included comprehensive torque specifications, which indicated that the T30 bolts should be tightened to 8 Newton meters (Nm).

Initially, I used the recently acquired components from the repair kit, and both of them fractured before to reaching the 8nm threshold.

Subsequently, I attempted to reuse the initial BMW components, but had the same issue: one of them broke before reaching 8 Newton meters of torque, while the other had its thread stripped at the end.

I have purchased four brand new items from BMW. During a phone conversation, I verified the torque setting, however they informed me that the setting has been increased to 10nm.

I am now experiencing some anxiety since both the new, aftermarket ones and an original BMW part have broken off, even at a length of 8 nanometres.

Given that I am now required to work with components that have a size of 10 nanometres, I am understandably concerned about the possibility of breaking the new components or damaging the threads on the ends of the camshaft.

Has anybody had this problem? Have you resolved it? Have I just been really unfortunate?

An 8nm gap is not very narrow, and neither is a 10nm gap. I understand that the old ones, being 23 years old, may explain why they are breaking and cannot be reused. However, it is surprising that even the new ones, regardless of being aftermarket, are also experiencing the same issue of snapping.

One of the aftermarket parts broke even after I reduced the torque to 7 Newton meters.

I am optimistic that the new BMW models will be satisfactory and effectively resolve the existing problems. I plan to first do the task manually and cautiously, and then gradually transition to using a torque wrench. My intention is to ensure that the VANOS system, which now seems aesthetically pleasing, does not fail unexpectedly.

[Darrellll]

Perhaps the issue is with the wrench rather than the bolts?

[Matt865]

This wrench is fresh new, however I decided to reduce its torque setting to 7nm.

I suspect that the issue lies with the inexpensive and low-quality aftermarket bolts, as well as the 23-year-old original bolts.

I am interested in purchasing the latest BMW models, since I believe they will meet my requirements.

[badgx]

Can the torque wrench be used for left-handed threads?

[Matt865]

I had not considered it, but I have now verified that my model is really dual. However, your thinking is commendable!

[VWDaveBMW]

Which specific kind of wrench are you referring to and what is the range of sizes it can accommodate?

In order to achieve a torque of 8 Newton meters with precision, it would be best to use a torque wrench with a range of around 16 Newton meters. However, using a torque wrench with a range of 20 Newton meters should still be acceptable. Therefore, your desired torque value falls within the centre region of the operating range. If your wrench has a torque rating of 120Nm, it will never correctly or consistently reach a torque of 8Nm since it exceeds its designed range of operation.

To get the highest level of accuracy, it is recommended to recalibrate the device based on fundamental principles, specifically for a torque value of 8Nm.

[MrGreedy]

At a distance of 8 nanometres, it would be very difficult to break a matchstick. Which torque wrench are you utilising? It is precisely tightened with a 1/4" drive ratchet.

[Matt865]

The range is limited to a maximum of 20nm. Purchased specifically for this task and several other tasks related to the engine compartment.

[WordSmith]

When I performed the rebuild, I just tightened the components by hand, and I have not had any issues for over many years.
In my last automobile, I applied torque to the specified amount.
Bolt was initially designed for reusability and had no issues with snapping.