Another timing issue thread (S54)

[AZ-LSB-M3]

So I’ve been tackling timing issues all week with my S54 after doing vanos preventative maintenance but now when it comes to bolting everything up, I can’t seem to get the timing just right. I have watched dozens of videos and read various threads about the process as well as looked at the beisan’s and ECSTuning’s guide but nothing seems to be working. The timing throughout the whole process mating the vanos with the engine is correct. Then when I go to rotate the engine to tighten up all the bolts and go back to TDC, the timing on the exhaust cam is always off.

Here are a couple of videos I’ve been following to try and get the timing correct:

https://youtu.be/_nMUCe7TD2o?si=swWH71BYjdKQeqxR

https://youtu.be/DxUwd4aTWzw?si=T4WlG4iE0-AzwHTn

https://youtu.be/kbX1vfki75g?si=qcB6qB2jErwMPScO

Even though my exhaust hub wasn’t snapped I still replaced it with beisan’s exhaust hub as well as used their oil pump disk. I also replaced the diaphragm spring set with the S62 pair just in case any of that info matters.

I also found the “sweet tooth” on both splines which you can see marked in the video below.

Here’s a short 6 minute video of the entire process I go thru every time that just doesn’t seem to work. If you skip to around the 4:00 minute mark you can see the issue I’m having. Does anyone see what I’m doing wrong during this process? Is that amount of lift on the cam timing tool ok? Or should I try and loosen all the exhaust hub bolts again and adjust the cam once more? I appreciate any info!

https://youtu.be/YJpF3tLr6CI?si=kOQYSpWyNGzjvyAl

[sapote]

Here’s a short 6 minute video of the entire process I go thru every time that just doesn’t seem to work. If you skip to around the 4:00 minute mark you can see the issue I’m having. Does anyone see what I’m doing wrong during this process? Is that amount of lift on the cam timing tool ok? Or should I try and loosen all the exhaust hub bolts again and adjust the cam once more?

So the EX cam is set too retarded (the bridge leg on the intake side lifted). What caused the issue?

1. was the chain tight on the pulling side (opposite side of the tensioner), and between the two sprockets? A little slack on the chain can cause cam timing retarded. When turning the crank to TDC, never ever turn it CCW to adjust the position.
2. You didn't know or verify that the EX piston was at its max forward before tighten up the 2 bolts pulling the vanos to the head. If the pistons were not at their max forward then while tightening the vanos to the head, the pistons could move instead of the pretensioned hubs move, leading to retarded timing.

To ensure that the pistons are at max forward, remove the caps, push pistons protrude out about 5mm, then bolt down the caps to set the pistons at max forward.

As about setting the 5mm gap between vanos and head, I would set this gap 10mm to give you more chances of pushing the pistons to their max forward during tightening up the vanos to the head.

[BL92]

Follow TIS, under the section setting the timing

you are skipping the pretension stage on the hubs that is why you are having trouble

As per TIS, Install the splines first,

insert the splines only a few mm,

then install the vanos unit to the spines

Tighen 2 hub bolts on each side with spanner snug

remove the vanos unit, then torque all hub bolts down

reinstall vanos unit



Follow Sapote, He is spot on and got mine perfect = Read this entire thread from start to finish