Cam Bolts and Valve Timing

[mike519]

Hi all,

OK, the ticking has been getting worse lately. It is still loudest at around 3k-3.5k but it can be heard a little even at idle now. I also hear a bit of gear whine that I don't believe was there before.

I am going to go in and do the valve adjustment again and shim to minimum spec as I have read. I am also going to tighten the retaining clips as I understand they can also cause a tick/rattle on occasion. Tonight I took my mechanic's "stethoscope" to the engine while running and the ticking does NOT sound like its coming from the area of the vanos cover (not as loud as elsewhere). I hear it all around the valve cover, a little louder around the back of the engine.

I had been wondering about cam bolts but am I correct in assuming that if it is not as loud around the vanos cover as around the back that it is not likely vanos or cam bolt related?

I had thought I might take the vanos assembly off just to check the cam bolts but wondered a) how difficult it is to take the vanos assembly off and on again (I know it will need a new gasket) and b) if there is an y danger in doing this just to check.

Also, in regards to posts about having to retime for those that do the bolts themselves, am I just missing something or can you not just remove one bolt and replace it at a time before moving on the next so as not to screw up the timing?

Thanks

[O-cha]

Originally Posted by mike519

I had thought I might take the vanos assembly off just to check the cam bolts but wondered a) how difficult it is to take the vanos assembly off and on again (I know it will need a new gasket) and b) if there is an y danger in doing this just to check.

Also, in regards to posts about having to retime for those that do the bolts themselves, am I just missing something or can you not just remove one bolt and replace it at a time before moving on the next so as not to screw up the timing?

Thanks

Yes, you're missing a lot of things including a basic knowledge of how the vanos mechanism works (I have explained it many times in the past and really don't feel like doing it again). Please take my advice and don't attempt this. Unfortunately there's probably no one you can trust to do it either.

[StickMon]

If you pull the head cover to do a valve adjustment, you may be able to tell if the Vanos bolts are backed out. You can see the tips of the bolts on the back side of the camshaft flange. They should all be just sub-flush, and equal.
If a couple or three are set deeper than the others, they're backing out and probably sheared. The intake bolts are the ones that always go.
You can also check the exhaust hub tangs while you're in there.

As for removing the Vanos and the timing.
1) The Vanos doesn't clear the front of the engine bay. There are a couple of ways to deal with this. None of them are pretty.
2) You can remove the bolts that break one at a time and replace them. The problem is that you have to remove all the parts that control the critical timing to get to the bolts that break. Do a search and read for a couple of hours. There's lots of threads on it. Beware of M3 threads that make it look easy. The M3 is much easier to work on.

[RobertRO]

2 years ago I attempted to do the Vanos bolts myself, but ended up at the dealer.
There's an array of special tools that you must have, otherwise you cannot set the Vanos correctly.
If you have ALL those special tools and you're comfortable with the TIS, then you can do it. It's no rocket science.
Otherwise, take it to the dealer or a trusted service shop.

[O-cha]

Originally Posted by StickMon

2) You can remove the bolts that break one at a time and replace them. The problem is that you have to remove all the parts that control the critical timing to get to the bolts that break. Do a search and read for a couple of hours. There's lots of threads on it. Beware of M3 threads that make it look easy. The M3 is much easier to work on.

Even on the M3 you cannot get to the bolts without losing timing, the clearance has nothing to do with it (just makes it more difficult).

Do not listen to these idiots telling you you can make sharpie marks and re-align things, it might keep you close enough not to throw a code, but the engine will absolutely not be in time, and it will not have the appropriate pretension on the gears.


I have timed more than a few S54s.

[Blind32]

Just hit ~65k, Engine running stronger than ever. Changed my cam bolts at ~20k.

It's not an easy job. Research is very important because you can get to a point where you say, damn I wish I would of noted where this piece aligned, and now you are trapped. Definitely understand it 130% before you even consider attempting it. Also you should have a very solid mechanical knowledge.

[mike519]

Yes, you're missing a lot of things including a basic knowledge of how the vanos mechanism works (I have explained it many times in the past and really don't feel like doing it again). Please take my advice and don't attempt this. Unfortunately there's probably no one you can trust to do it either.

Not sure you needed to answer with that tone. I did do a lot of reading last night before I posted this but had a couple of questions I wasn't clear on.

You don't want to repost something you have posted before, no problem, then ignore the post.

[mike519]

Thanks guys. Didn't realize I had to go that far to inspect the bolts. I will take a look at them from behind.

Sounds like I will have the dealer or an Indy do the timing.

[beta]

Check my thread on Exhaust hub upgrade.

You would need the special tools, and you'd need to tilt the engine up for proper access to the vanos from the front. I recently went through all of it, and ended up only being able to adjust my valves.

[StickMon]

beta,

Exhaust hub upgrade didn't pan out? I was watching for an update to your thread.

[O-cha]

Originally Posted by mike519

Not sure you needed to answer with that tone. I did do a lot of reading last night before I posted this but had a couple of questions I wasn't clear on.

You don't want to repost something you have posted before, no problem, then ignore the post.

Didn't realize you could hear me typing. You asked if you were missing something, you are and I stated that. What you're missing isn't even the complicated parts, it's the most basic understanding based on your questions. Just the way it is.

[mike519]

Originally Posted by O-cha

Didn't realize you could hear me typing. You asked if you were missing something, you are and I stated that. What you're missing isn't even the complicated parts, it's the most basic understanding based on your questions. Just the way it is.

Feel free to ignore my future posts. You've been more than helpful here.

[beta]

Originally Posted by StickMon

beta,

Exhaust hub upgrade didn't pan out? I was watching for an update to your thread.

My last post in that thread goes into it. There's not enough room in front of the vanos without securing (aka tilting) the engine.

Originally Posted by mike519

Feel free to ignore my future posts. You've been more than helpful here.

O-cha is a bit harsh, but his point is a valid one. Your questions show you haven't looked at the material too deeply.

The thread I linked has all the information, tons of pages from the TIS, lists of tools, etc. The amount of research that I had to do was substantial, and in the end still not enough because there are a few key differences between the e46 and the z4m, like our sawed in-half flywheel pin.

As for the ticking, have you compared to another engine? It could be normal, S54s are fairly noisy.

[StickMon]

Originally Posted by beta

My last post in that thread goes into it. There's not enough room in front of the vanos without securing (aka tilting) the engine.

Oh, OK. I thought you were going to attempt it.
I was waiting to see your results before I would even consider it.
What was never clear to me was how many things you have to disconnect (steering, exhaust, etc.) before you can tilt it enough.
Not sure that this thread is a fair indicator, since he also had to remove his oil pan and timing cover to retrieve the exhaust hub tang.

I'm not sure what the indie mechanic did to get mine off. I don't think he tilted the engine, but I'll never know.
He said he had to remove the radiator, so I assumed he disassembled the front of the engine bay. For all I know, he removed the entire front of the car.

I don't have a desperate need to remove mine, but I'm at 86k miles and putting miles on fast. I'd like to do a Beisan rebuild and maybe an upgraded exhaust hub between 100k and 125k miles.

[mike519]

O-cha is a bit harsh, but his point is a valid one. Your questions show you haven't looked at the material too deeply.

The thread I linked has all the information, tons of pages from the TIS, lists of tools, etc. The amount of research that I had to do was substantial, and in the end still not enough because there are a few key differences between the e46 and the z4m, like our sawed in-half flywheel pin.

As for the ticking, have you compared to another engine? It could be normal, S54s are fairly noisy.

No, the ticking is getting worse and pretty loud at times.

The problem I find with this site is the searches are hard to narrow down. I searched for "cam bolts" and got tons that had nothing to do with this. I found a few posts that gave me some info but not enough to help me answer my questions i had not seen yours. I went to the Dr Vanos site and read his instruction PDF but it made it sound a ton easier than you guys are describing, hence the confusion.

I do realize that I know little about this setup, that's why I am trying to learn. I was a mechanic back in the late 80's and early 90's but never heard of vanos. All someone needs to do in a reply is as you did (post a link) or ignore. I never get why people get bent out of shape if someone missed info in a search or even if they didn't search...nobody forces a reply. Everyone has the right to ignore something that bothers them but most these days seem to be confrontational rather than ignore.

Anyway, took the valve cover off last night and cam bolts appear fine...none loose that I can see. Will be adjusting valves in the next few days. I am concerned there is something more sinister going on here though. Fingers crossed.

[inTgr8r]

I'd really like to hear what you're dealing with Mike.
...must be driving you crazy.

[StickMon]

Here's a thread that may help you with the diagnosis.
Post #21 shows what they look like when removed.
I have a sack at home just like that.

I had mine replaced by a "reputable" indie BMW specialist who had done this job on several M3s, but never a Z4.
He had a heck of a time with it, and didn't get the camshaft timing correct.

[mike519]

Originally Posted by inTgr8r

I'd really like to hear what you're dealing with Mike.
...must be driving you crazy.

Yup!

If no joy with the valve adjustment, maybe I will take a drive over your way Ian. I could use a vet's opinion!

[mike519]

Originally Posted by StickMon

Here's a thread that may help you with the diagnosis.
Post #21 shows what they look like when removed.
I have a sack at home just like that.

I had mine replaced by a "reputable" indie BMW specialist who had done this job on several M3s, but never a Z4.
He had a heck of a time with it, and didn't get the camshaft timing correct.

Thanks! I will check that thread out tonight.

[O-cha]

Originally Posted by mike519

Feel free to ignore my future posts. You've been more than helpful here.

It not all about you... You realize other people read the forum too right?

Originally Posted by StickMon

I'm not sure what the indie mechanic did to get mine off. I don't think he tilted the engine, but I'll never know.
He said he had to remove the radiator, so I assumed he disassembled the front of the engine bay. For all I know, he removed the entire front of the car.

He would have had to, there's a framing between the radiator and the vanos that would have made removing the radiator pointless without removing, which takes a lot of disassembly.

There's an actuator that makes it fairly easy even with the z4 clearance though. Just changes the procedure around a little to get the pretension right.

[beta]

Originally Posted by StickMon

I'm not sure what the indie mechanic did to get mine off. I don't think he tilted the engine, but I'll never know.
He said he had to remove the radiator, so I assumed he disassembled the front of the engine bay. For all I know, he removed the entire front of the car.

That's the other way to do it. You have to remove a lot of the front of the car, or tilt the engine.

The reason we have to go through a lot of extra work, is that the Z4 has a brace right up against the vanos. So there's not enough room in front of it. Part of the process involves using two of the longer bolts to move the vanos back but still keep it aligned.

Originally Posted by StickMon

I don't have a desperate need to remove mine, but I'm at 86k miles and putting miles on fast. I'd like to do a Beisan rebuild and maybe an upgraded exhaust hub between 100k and 125k miles.

Same here, right now my work hours are out of control, but I am going to attempt this again, just need more tools and a lot more free time.

Originally Posted by mike519

I went to the Dr Vanos site and read his instruction PDF but it made it sound a ton easier than you guys are describing, hence the confusion.

The TIS only covers the e46, so there's a few things that are wrong. As I mentioned above we don't have enough clearance, and we need to saw the flywheel pin in half (because of the same clearance issue). I also found you need a socket to spin the engine (rather than the special fixing tool, which I bought and is now staring at me uselessly). There's more and I think I documented most of it in the thread.

Originally Posted by mike519

Anyway, took the valve cover off last night and cam bolts appear fine...none loose that I can see. Will be adjusting valves in the next few days. I am concerned there is something more sinister going on here though. Fingers crossed.

Just in case, the visible bolts are not the ones that loosen up, did you look from the back?

[beta]

Originally Posted by O-cha

There's an actuator that makes it fairly easy even with the z4 clearance though. Just changes the procedure around a little to get the pretension right.

Is there enough clearance if you use the actuator? That does make sense. The reason we needed extra clearance was to remove the vanos caps, so we can actuate it by hand, rather than using the 300$ actuator.

I also don't have an air compressor, but there's a DIY mechanic shop around me that has all the tools.