Z4 Coupe Tappets

[RustyGoldsacks]

Help needed from my fellow Z4 Coupe'rs...

About 3 months into owning a new 3.0 Si Se, I started to hear a tapping sound coming from the engine (Tappets?). It speeds up as I rev higher, but thought this to be rather peculiar for such a new car.

I took it into BMW and they told me this is a common experience in this range, but I am quite baffled as to the truth of their statement.

Is this true guys? I haven't seen any blogs to verify this...

[jezzaaa]

Hi ya - mine's an M Coupe, but I don't get any tappet sounds...what I do get is some slightly unhealthy but mild sounding cam/valve gear noises when keeping the engine at a constant speed in the mid rev range!!

[RustyGoldsacks]

Thanks Jezzaa.

This happens when I start the car and just idling, so nowhere close to mid-range. It's really annoying and rather embarrassing because it sounds like a diesel engine in a batmobile outfit!

I'm hoping that fellow Z4'ers can back me when I argue with the supplier that this is not a common characteristic of a 3.0 si se.

I spoke to a BMW Specialist who said I shouldn't accept their comment and insist on an appropriate course of action!

[wrighty78]

RustyGoldsacks said:

I'm hoping that fellow Z4'ers can back me when I argue with the supplier that this is not a common characteristic of a 3.0 si se.

Certainly NOT something I've experienced with mine over the last 16 months and 10k miles.

[ian in lancs]

The M engine, S54 IIRC does sound rattly at about 3250rpm (mechanical sprung cams/followers). I had it listened to by about 4 BMW dealers all said the same; 'they all (M's) sound like that'! I stopped worrying about it after that.

As for the std 3.0 I don't know but my 2.5 briefly rattled as it started up, presumably as the oil pressure built up (hydraulic tappets) built up. It certainly didn't rattle after that. I'd get a second opinion.

[AlexE46]

My 3 series had it and i took it in under warranty - they told me it was just the valves and it was meant to make the noise! Not convinced.

[RustyGoldsacks]

Thanks Alex. I hate being fleeced like this. I've never heard a 3 series make this noise either and if meant to be like this I'd expect every model to do the same. I'm off to BMW on Monday with all your very gratefully received feedback. Hopefully I have even more by then.

Cheers All!

[8Tech]

An MCoupe will certainly have some valvetrain noise but not an M54 3.0
Check engine oil level first, it can be a sign of low oil level.
Sounds like they are blagging you until the warranty expires then hit you with a big 'un.

8Tech.

[Carolineccb1]

My Z4C is a year old, about 12k miles on the clock. So far, so good - no problems...... Hmmmm, it'll implode now I've said that!

Good luck for a speedy recovery!

[RustyGoldsacks]

Sounds like a sensible explaination, but if this were the case, I would have expected more Z4C drivers to back this up. Anyone else out there with the same experience?

[pgilc1]

RustyGoldsacks said:

Sounds like a sensible explaination, but if this were the case, I would have expected more Z4C drivers to back this up. Anyone else out there with the same experience?

No, but ours does long runs daily. Does a long run cure yours? Any chance of taking it to another dealer for a second opinion?

[gavmobile]

My 130i (same engine) does this. Not quite to the point of annoyance but it is there. I agree with the poster above though, I do tend to leave it standing for long periods and it does seem to go away after really long journeys. Will mention it next time it's at the dealers.

[8Tech]

Air mixing with the oil? I don't think so!

The tappetts are draining oil from the non-return valve when they are left standing which leaves an air pocket in the tappett. When you start the engine, that air pocket is easily compressed causing excessive valve clearances, this is the rattling you can hear.
Once engine oil pressure refills the tappetts, valve clearances tighten-up as the oil purges the air until valve clearances are effectively zero, hence quiet engine. Oil is effectively incompressible.
SO
You have to decide whether or not the non-return valve is defective or not and to what extent.
It is fair to allow some pressure loss over a couple of weeks but they should "pump up" within seconds. This also depends on engine oil grade and the most common cause of tappett valve failure is incorrect oil viscosity and irregular oil changes leaving deposits in the lubrication system.
This is so common, there are even tappett(cam follower) flushing products available specifically for this. I would try one of these, then do an oil and filter change with a quality oil of the correct viscosity for our car.

HTH

8Tech.