order to address known concerns on Z4m's

[Bossdog]

I acquired my 06' Z4MR last summer and Just Love it. I plan to keep it for as long as possible. It has 40K miles and is pristine, Completely stock! The engine bay looks like it just came off the showroom floor.

I plan to invest in it each Spring, one issue at a time or around $1K each season. I have just completed its first valve job and changed all fluids, Engine, Diff, Trans. CDV removal and Brake fluid change after Easter. I have not Flushed the Coolant system yet.

What order should I address the known issues. Please give your order of importance. Importance = likely hood of occurrence x impact of failure.

Vanos Bullet-proofing

Rear Spring breakage

Water pump (at what mileage or age?)

Bushing failures (which ones? RTAB?)

Engine bearing ware (what mileage)

Engine mount bolts

Upper Timing Chain Guide Rail ??

What else?

Thanks for everyone's input.

[StickMon]

Do you know if the camshaft spline sleeve bolts behind the Vanos are hex head or torx head?
BMW upgraded them some time in 2006. The hex head have a 100% chance of failure.
It can end very badly, but you'll have some fair warning. It'll sound like a coffee can full of marbles being shaken.
You want to address that asap. The rest you have plenty of time to worry about.

[SaltyNC]

StickMon I think I already know the answer to this, but there isn't any way to know about the bolts other than to pull the cover on the vanos is there? I'm guessing a build date cut-off was never identified? As it turns out, my car was built today.

Salty

[Bossdog]

Originally Posted by StickMon

Do you know if the camshaft spline sleeve bolts behind the Vanos are hex head or torx head?
BMW upgraded them some time in 2006. The hex head have a 100% chance of failure.
It can end very badly, but you'll have some fair warning. It'll sound like a coffee can full of marbles being shaken.
You want to address that asap. The rest you have plenty of time to worry about.

I do not know. My Mfg date is June 24/06'

[SaltyNC]

I recently did everything on your list including the coolant flush and engine mount bolts, but I was also doing engine mounts and trans mounts. The vanos is always a worry in the back of my mind, so after a new set of tires, it will probably be the next thing on my list just for peace of mind.

Bushings are probably the next logical step for both of us. Rear trailing arm, front control arm. When I do it, I'll also install the RTAB limiters. Not on your list, but shocks may be going in addition to the springs. I'm going to replace with coilovers when the time comes.

I'm planning to address the other issues you mentioned (water, bearings, etc) when I reach the 60-70K range.

Salty

[StickMon]

Originally Posted by SaltyNC

StickMon I think I already know the answer to this, but there isn't any way to know about the bolts other than to pull the cover on the vanos is there? I'm guessing a build date cut-off was never identified? As it turns out, my car was built today.

Salty

Sadly, I don't think there's any way to know without pulling the Vanos and a sprocket hub.

To answer a couple more of the OP's questions, I did my timing chain guide at 118k, and it was in pretty sad shape. I would recommend 100k.
Replace or rebuild the Vanos at the same time. Seals will be pretty knackered.

Did the rod bearings at 128k after 2 consecutive Blackstone reports came back with sharply elevated lead.
Get regular Blackstone reports and watch the lead. Life of the bearings depends a lot on how you drive.

[Bossdog]

Apparently there is a small plastic filter in the Vanos.

Is this something that should be cleaned/changed prior to a full upgrade of the Vanos? The DYI on ECS for the E46 looked pretty simple.

[XMetal]

That Vanos filter is a pretty simple DIY. Parts are only about $25 (if you don't do it with the Beisan kit). Most people do it at the same time when they do the Beisan upgrade because a couple of the rubber sealing rings are included in one of the Beisan kit. I think you should be fine as the screen of that filter is pretty coarse anyway. 99% of the debris should be trapped by your oil filter, if you properly maintain your car, IMHO.

[StickMon]

I've changed it a couple of times during valve adjustments.
Never found any dirt or swarf on it, even after driving for who knows how long with a broken exhaust hub tab.
All the swarf from the tab ended up on my Dimple oil drain plug.
The consensus here is that suppliers are just hyping it to make money.

[jdoublehcubed]

Originally Posted by StickMon

I've changed it a couple of times during valve adjustments.
Never found any dirt or swarf on it, even after driving for who knows how long with a broken exhaust hub tab.
All the swarf from the tab ended up on my Dimple oil drain plug.
The consensus here is that suppliers are just hyping it to make money.

All you need to change is the filter, not the o-rings. I think its about $12, i added it to my list of stuff to do at each valve inspection. For that cheap I don't see any reason not to replace it.