Timing after Vanos installation

[Cubieman]

My exhaust timing was a bit off after I installed the Vanos and and I am having a bit of an issue adjusting it.
In the Beisan anti-rattle procedure right at the end it decribes how to adjust timing post vanos install. I have followed the procedure and it doesn't seem to be helping.

http://www.beisansystems.com/procedures/s54_vanos_rattle_procedure.htm

(Said timing instructions are at the very bottom)

Summation:
- With crank at TDC with cyl 1 cam loosen top 3 sprocket bolts.
- Turn Crank to TDC again and insert crank locking pin. (Cylinder 1 cam lobes are now roughly pointing at each other)
- Retard cams and loosen remaining 3 sprocket bolts that are now accessible.
- Using bridge tool rotate (CW rotation in my case of exhaust cam) cam(s) until the bridge sits flat on head with pin installed.
- Tighten 3 top sprocket bolts a bit
- Turn engine to TDC tighten 3 sprocket bolts to 14nm (by hand)
- Turn engine over again to TDC (cam lobes pointing to each other) and finish tightening top 3 bolts to 14nm
- Cams should now be in time

I have done this 3 times and my exhaust cam doesn't seem to be adjusting at all, do I need to remove the vanos to really re-time the engine? What could I be doing wrong here?

[Lukem3]

Make sure you're retarding the cams before loosening the 3 bolts. The vanos holds pressure, this step is done easier with the valve body removed. U dont have to remove the vanos, just remove the valve body from the vanos.

Sent from my SM-G955U1 using Tapatalk

[sapote]

My exhaust timing was a bit off after I installed the Vanos and and I am having a bit of an issue adjusting it.
?

How much off — retard?
That procedure won’t help.
1) need to remove Vanos and start over again
2) you could add some advance to the cam before bolting up the Vanos: crank at TDC compression stroke, turn EX cam a tiny bit pass bridge pin (bridge foot lift off the head on exhaust side 2mm)
3) bolt the Vanos to head and finish bolting the hub 6 bolts as normal.

[sapote]

Op, next time after bolting the Vanos to head and the top 3 hub bolts, insert the bridge pin to check the cams timing, before rotating the crank to bolt down the hub remain other 3 bolts. If the pin won’t go in freely, then you had not backed out the hub bolts enough which caused the cam being turned during bolting down the Vanos.

[Lukem3]

Op, next time after bolting the Vanos to head and the top 3 hub bolts, insert the bridge pin to check the cams timing, before rotating the crank to bolt down the hub remain other 3 bolts. If the pin won’t go in freely, then you had not backed out the hub bolts enough which caused the cam being turned during bolting down the Vanos.

That doesn't seem to be the issue, sounds more like op is adjusting the ex cam when advanced. The intake side he's not having an issue with which is normally retarded. If he wasn't loosening the bolts enough, he'd have the same issue on the intake side.
99.9% the cam isnt retarding before adjustment because of vanos pressure, removing the valve body will remove the pressure.
No need to remove complete unit, if the splines arent installed correctly it would still time fine, he would just have limited adjustment.


Sent from my SM-G955U1 using Tapatalk

[Lukem3]

How much off — retard?
That procedure won’t help.
1) need to remove Vanos and start over again
2) you could add some advance to the cam before bolting up the Vanos: crank at TDC compression stroke, turn EX cam a tiny bit pass bridge pin (bridge foot lift off the head on exhaust side 2mm)
3) bolt the Vanos to head and finish bolting the hub 6 bolts as normal.

Dont do this, if everything is fine, it should be enough to follow the beisian procedure. People have been using that method for decades with no issues. Dont start randomly retarding or advancing the cam to try to "fix the issue"
If it's not timing correctly with the beisian procedure something is wrong or ur missing a step. (back again to the cam retard)

Sent from my SM-G955U1 using Tapatalk

[sapote]

That doesn't seem to be the issue, sounds more like op is adjusting the ex cam when advanced. The intake side he's not having an issue with which is normally retarded. If he wasn't loosening the bolts enough, he'd have the same issue on the intake side.
99.9% the cam isnt retarding before adjustment because of vanos pressure, removing the valve body will remove the pressure.
No need to remove complete unit, if the splines arent installed correctly it would still time fine, he would just have limited adjustment.


Sent from my SM-G955U1 using Tapatalk

The issue is either the hub bolts were too tight causing the cam being turned during bolting the Vanos, or the pistons were not pushed forward to their max (retarded).

This is why I asked him to check the cams with bridge pin before rotating the crank. It costs nothing to do.

[Cubieman]

I've got the valve body off the vanos, it sounds like it may need to be removed and tried again. The only big difference is with the spines I used the "sweet tooth" upon insertion which made a big difference in the amount the hubs had to rotate CCW. Both splines basically slide right in without having to rotate the hubs CCW very much at all.

When I remove the vanos could I simply loosen all hub bolts and just pull out the vanos/splines together or is it important to leave the splines in there and unscrew the shafts from the vanos pistons?

I wonder what I did wrong to have it timed, then after the vanos was pressed on it came out of time. The Exhaust cam is off and the Intake cam now requires my to push in the pin really hard in the bridge whereas before vanos install it slid in easily.

The cams must have moved a bit during the bolting of the vanos to the head is what I understand to be the problem, I didn't have the 4 hub bolts you tighten and then loosen 1/4 turn loose enough possibly.

[sapote]

I've got the valve body off the vanos, it sounds like it may need to be removed and tried again. The only big difference is with the spines I used the "sweet tooth" upon insertion which made a big difference in the amount the hubs had to rotate CCW. Both splines basically slide right in without having to rotate the hubs CCW very much at all.

When I remove the vanos could I simply loosen all hub bolts and just pull out the vanos/splines together or is it important to leave the splines in there and unscrew the shafts from the vanos pistons?

I wonder what I did wrong to have it timed, then after the vanos was pressed on it came out of time. The Exhaust cam is off and the Intake cam now requires my to push in the pin really hard in the bridge whereas before vanos install it slid in easily.

The cams must have moved a bit during the bolting of the vanos to the head is what I understand to be the problem, I didn't have the 4 hub bolts you tighten and then loosen 1/4 turn loose enough possibly.

I address each bolded highlighted text above as numbered below:

1) When the spline shaft slid into the hub, its helical cut should rotate the hub the exact amount just like when screwing down a screw or a bolt -- it all depends on the threads pitch or the slop of the helical cut which is a fixed value in this case. You sounded as if there are 2 different helical cut on those splines and confusing.

2) sure you could loosen all the hub bolts for removing the vanos easier. I prefer to loosen then instead of trying to turn the cam retard for the same effect.

3) 2 things could went wrong in your process: either the pistons were not at their most forward location, or the hub bolts were too tight which caused the cam to turn during bolting down the vanos.

4) as said in (3) and yes, it's possible.

[Cubieman]

I think I am going to pull the vanos/shafts out and re-time and re-install vanos with the same one time use vanos gasket and hopefully get the hub bolt sequence correct and find the engine timed correctly.

That (above) will have been a "practice run"

After that I have remove the vanos again and install "for real" with new gasket.
Is there any issues as far as using the vanos mounting bolts multiple times?

I don't seem to have had much luck re-timing with the vanos installed. The exhaust cam needs to be moved CW (Advanced) to have the timing pin/bridge in the correct position flat on head. Also, on the intake side the bridge sits flat but it takes effort to put the timing pin in so I feel like I lost my timing there as well to some extent.

I will basically just be pulling the vanos, doing a practice run using the same (bad) gasket then if all goes well doing it again with a new gasket.

Another question, how much slack should there be in the timing chain approximately? I can move the chain up/down a bit in the middle of the sprockets. When I removed the chain tensioner I manged to dump most of the oil out of it, there is still a spring in it however. The amount of play in the chain seems to be excessive to me but I don't know these things and it appears the timing chain tensioner is hydraulic so I assume it tightens if neccessary once the engine is running.

[eacmen]

Pro Tip:

When bolting the vanos up to the head i insert two long dowels in the cam holes. This allows me to visually see if the cams are moving as I bolt the vanos up to the head. Its very easy to not notice a degree or two movement of the cams. With that long dowel/screwdriver in there that one deg rotation turns into a long arc that is easily noticed.

Do not use the alignment bridge to “lock” the cams in place while bolting the vanos up.

[Cubieman]

Pro Tip:

When bolting the vanos up to the head i insert two long dowels in the cam holes. This allows me to visually see if the cams are moving as I bolt the vanos up to the head. Its very easy to not notice a degree or two movement of the cams. With that long dowel/screwdriver in there that one deg rotation turns into a long arc that is easily noticed.

Do not use the alignment bridge to “lock” the cams in place while bolting the vanos up.

Nice, I'll use that as I have just removed the vanos in order to re-time it. I think I'll do a practice run and if that works use my remaining vanos gasket.

I wish one could torque the hub bolts with the vanos off, I still don't fully understand why that isn't a viable option.

[eacmen]

Nice, I'll use that as I have just removed the vanos in order to re-time it. I think I'll do a practice run and if that works use my remaining vanos gasket.

I wish one could torque the hub bolts with the vanos off, I still don't fully understand why that isn't a viable option.

Basically you can’t allow the cam to move and the vanos pistons need to be at full retard when it is bolted up to the head. So cams and vanos both need to be at full retard. If you tightened the hubs down then the vanos the pistons cannot be attached to the splines with the vanos bolted to the head and you can’t bolt the vanos to the head without moving the spline which would move the cam with the hub bolts tightened.

[sapote]

I wish one could torque the hub bolts with the vanos off, I still don't fully understand why that isn't a viable option.

In theory you could insert the spline shaft into the hub and torque the hub bolts down, then connect the Vanos shaft and bolt down the Vanos. But, how do you time the hub to the sprocket as the sprocket has long slots and not round holes? This is the reason when bolting down the Vanos it pushes to rotate the hub to the right location to time the hub on the sprocket then the pair locked up together by torquing the hub bolts.
Do I say clear or just more confusing?

[Cubieman]

In theory you could insert the spline shaft into the hub and torque the hub bolts down, then connect the Vanos shaft and bolt down the Vanos. But, how do you time the hub to the sprocket as the sprocket has long slots and not round holes? This is the reason when bolting down the Vanos it pushes to rotate the hub to the right location to time the hub on the sprocket then the pair locked up together by torquing the hub bolts.
Do I say clear or just more confusing?

No, this makes sense, thank you!