Engine won't time post Vanos install

[Cubieman]

In the video the chain is tight so it’s not a problem.
No chain slack on pulling side: viewing from front the crank pulled the cam sprockets CW, hence the pulling side is on the right, not chain tensioner side.

Do this if you want perfect timing, starting from beginning for a normal working car:
1) Turn crank cw to TDC but stop at about 2mm before TDC mark. This will cheat and give the cams little advanced timing to correct your issue. Don’t need to lock crank with pin.
2) do the remaining steps as you did before with cams timed by the pin and bridge sit FLAT on the head on both sides.

3) Turn crank 2 or 4 turns and check the final timing should be perfect.

Is it OK at this point to simply loosen the hub bolts with the Vanos still installed and re-adjust timing according to your steps or when you say to start from the beginning are you suggesting the vanos be removed from the head again?

Also after all this has been done I will have likely tightened/loosened the hub bolts 6-7 times, is that acceptable?

[sapote]

Whenever the hubs bolts are loosened, the Vanos has to removed!

[Cubieman]

Whenever the hubs bolts are loosened, the Vanos has to removed!

Included in the beisan procedure is a method to adjust timing with the vanos still attached, why is it important to remove the vanos when timing is off?

[sapote]

Included in the beisan procedure is a method to adjust timing with the vanos still attached, why is it important to remove the vanos when timing is off?

With hub bolts loosen the hub no longer timed to the sprocket and so it must be timed again. To time the hub, the only correct way is to have the Vanos pushing on the spline which rotates the hub to the precise position.

[Cubieman]

When I press the vanos/splined shafts onto the head the shafts are lined up (sweet spot) so I don't even have to turn the hubs CCW by hand at all for the splined shafts to insert, they just go right on in and the hubs turn CCW a bit without my help. This was not the case in their previous configuration before I took things apart, I don't see how that would have any bearing on my issue or be a negative, just thought I would mention that if it helped me not to have to take this damn thing off too many times. Separating the vanos from the head isn't something I want to do more times than necessary.

Sounds like setting the crank just past TDC and timing the cams from there is what needs to be done so I can at least get the timing bridge within .5mm of the head. My exhaust is about .650+mm off the head currently. Man this job is getting so old.

[sapote]

Sounds like setting the crank just past TDC and timing the cams from there is what needs to be done so I can at least get the timing bridge within .5mm of the head. My exhaust is about .650+mm off the head currently. Man this job is getting so old.

No, not pass TDC; set it just before TDC about 2 or 3mm on the pulley arc.

[krashdumie05]

I just did the vanos last week. I had the same problem with the cams losing timing after rotating the crank (reinstalled vanos 3 times) Finally, this is what I did.


1 I tightened the 3 bolts on each hub. Kinda tight.
2 rotated the crank and tightened the rest of the bolts as i rotated the engine.
3 I re pinned at TDC after 1 revolution.
4 checked timing
5 since my timing was off I used the 24 mm wrench and adjusted the cams till they were back in time.
6 I then continued tightening the hub bolts as I turned the engine over.
7. In my case I only had the readjust the cams once. By the second revolution the engine kept timing.


hope this helps

Fred

[sapote]

I just did the vanos last week. I had the same problem with the cams losing timing after rotating the crank (reinstalled vanos 3 times) Finally, this is what I did.


1 I tightened the 3 bolts on each hub. Kinda tight.
2 rotated the crank and tightened the rest of the bolts as i rotated the engine.
3 I re pinned at TDC after 1 revolution.
4 checked timing
5 since my timing was off I used the 24 mm wrench and adjusted the cams till they were back in time.
6 I then continued tightening the hub bolts as I turned the engine over.
7. In my case I only had the readjust the cams once. By the second revolution the engine kept timing.


hope this helps

Fred

I'm confused. After step 2 all 6 hub bolts were tighten and so no way the hub could turn relative to the sprocket when you tried to turned the cam with 24mm wrench to adjust the timing in step 5. What's going on?

[sapote]

When I press the vanos/splined shafts onto the head the shafts are lined up (sweet spot) so I don't even have to turn the hubs CCW by hand at all for the splined shafts to insert, they just go right on in and the hubs turn CCW a bit without my help. This was not the case in their previous configuration before I took things apart, I don't see how that would have any bearing on my issue or be a negative, just thought I would mention that if it helped me not to have to take this damn thing off too many times. Separating the vanos from the head isn't something I want to do more times than necessary.

Sounds like setting the crank just past TDC and timing the cams from there is what needs to be done so I can at least get the timing bridge within .5mm of the head. My exhaust is about .650+mm off the head currently. Man this job is getting so old.

If you didn't remove the spline shaft off the hub then no need to repeat the steps turning the hub CCW and insert the shaft on the first tooth. But the shafts need to be pulled away from the hubs by a minimum of 10mm or so.

There is 2 ways to cheat the chain slack or system plays: either advance the cams (bridge off the head by 2mm on EX side), or retard the crank (set it 3mm before TDC). I thought retard the crank is less work. But only do only one or the other and not both.

[Cubieman]

If you didn't remove the spline shaft off the hub then no need to repeat the steps turning the hub CCW and insert the shaft on the first tooth. But the shafts need to be pulled away from the hubs by a minimum of 10mm or so.

There is 2 ways to cheat the chain slack or system plays: either advance the cams (bridge off the head by 2mm on EX side), or retard the crank (set it 3mm before TDC). I thought retard the crank is less work. But only do only one or the other and not both.

I think I'll try retarding the crank, hopefully tonight.

Also, once everything is tight (hub bolts) and it is in time is it ok to remove vanos and leave splined shafts installed in order to put on a new vanos gasket? That doesn't disturb the timing correct?I've got one gasket left and don't want to have to potentially ruin it by taking the vanos off multiple times.

[krashdumie05]

I'm confused. After step 2 all 6 hub bolts were tighten and so no way the hub could turn relative to the sprocket when you tried to turned the cam with 24mm wrench to adjust the timing in step 5. What's going on?

Yeah all 6 were "tight" at that point but I guess not tight enough. My assumption is that I lost timing during the beginning of the crank rotation when only 3 of the bolts were tightened.

After i completed my first full revolution, all 6 bolts were tight. When repinned at TDC I was still able the adjust the cams.
I continued tightening the hub bolts as I rotated the crank around the second time.

It might be helpful to know that I used the s62 hub spring and washer

[sapote]

I think I'll try retarding the crank, hopefully tonight.

Also, once everything is tight (hub bolts) and it is in time is it ok to remove vanos and leave splined shafts installed in order to put on a new vanos gasket? That doesn't disturb the timing correct?I've got one gasket left and don't want to have to potentially ruin it by taking the vanos off multiple times.

How did you tighten all 6 bolts without removing the Vanos? Don’t turn the crank to get to the other bolts as this could move the hub. After tightening the top 2 or 3 bolts, remove the Vanos and torque all hub bolts to spec and replace the gasket at the same time. You can do anything you wish as long as the hub bolts not loosen then the timing won’t change.

[sapote]

Yeah all 6 were "tight" at that point but I guess not tight enough. My assumption is that I lost timing during the beginning of the crank rotation when only 3 of the bolts were tightened.

After i completed my first full revolution, all 6 bolts were tight. When repinned at TDC I was still able the adjust the cams.
I continued tightening the hub bolts as I rotated the crank around the second time.

It might be helpful to know that I used the s62 hub spring and washer

1) This is why I don’t turn the crank in order to tighten the lower 3 bolts. I removed the Vanos and torque all bolts to spec using socket, not open wrench.
2) You said all 6 bolts were tight, then how could you still able to adjust the cam timing after that?
3) the S63 plates do not affect this.

[krashdumie05]

1) This is why I don’t turn the crank in order to tighten the lower 3 bolts. I removed the Vanos and torque all bolts to spec using socket, not open wrench.
2) You said all 6 bolts were tight, then how could you still able to adjust the cam timing after that?
3) the S63 plates do not affect this.

1 thats in interesting method. I may try that next time. Although, I haven't seen that method in any diy instructions. Admittingly I haven't seen my method either.
2 I guess not tight enough
3 ok

[sapote]

1 thats in interesting method. I may try that next time. Although, I haven't seen that method in any diy instructions. Admittingly I haven't seen my method either.
2 I guess not tight enough
3 ok

1) People are too lazy or not thinking out of the box. TIS instruction is for mass production and using special open torque wrench. They don't have time for removing the vanos and use 10mm socket on the bolts.
2) If bolts were not tight enough then the hub would slip from cam sprocket when you turned the crank to get to the lower 3 bolts. Oh well, this method is so prone of errors.