Timing chain issue ?

Hmmm

That's an odd noise..

Given the position that you have taken that from my firsts thoughts would be the DISA
VALVE ...
 
Yeh, strange for sure. I just can't imagine how an oil filter would make that noise???. Here's what to do, get a 1m length of hose pipe, hold one end to your ear and put the other end to the various components around the engine. The loudest one should identify the culprit.
 
Well, James has changed the filter with an oem item and refreshed the oil and in short, it's made no difference :headbang: and also checked the top and bottom DISA valves which are both fine :headbang: so probably time to give up! James has gone out of his way to help me with this post sale and exceeded any reasonable expectations. Gonna have to take it on the chin and book it into a specialist for an expert diagnosis.

I just can't understand why it runs normally until fully warmed up, at which point the noise appears but performance is unaffected it seems. Any ideas? :poke:

Will keep members posted on here - the saga continues....
 
As Justin has posted, oil and filter changed - no change. Top and lower DISA valves removed and checked, both perfect (getting to that lower DISA is a right royal pain in the a**e).

In my opinion, I think this can be limited to a component that is rotational in nature, so potentially alternator bearings, idler gear, belt tensioner or something in the chain drive. All I did confirm today is that the noise starts at just above tickover and disappears at about 1300 rpm.

Time to get the car nice and warm so the noise is there, then remove the serpentine belt to see if the noise disappears.

Amy more thoughts or offers of help welcome. It's set to be sunny tomorrow, so you could always drop the roof (those with proper Z4's :rofl: ) and head to Peterborough to take a listen :D :D

Thx, James
 
Are all the bolts on the Alternator tight.Can you place the sound to an exact area by putting your ear to a long screwdriver and moving it about.Could you run engine with the serpintine belt off for a few seconds to try and eliminate certain parts.
Without being there to listen i know its all guess work.
 
Cooky3 said:
I have just found this on YouTube. The same issue I have it seems and possibly an oil filter problem. Really?

https://youtu.be/KXbAg90G7tY

Tried posting my vid - just need to find it now :cry:

I can confirm I had an issue with the oil filter straight after a change by my local main dealer. Can’t remember the sound. Might have posted about it on here. Singer sewing machine rings a bell, but dealer sorted. Also recall mine was doing it at idle. This was on a 2.5si n52 by the way.
 
Hi all. Apologies for the radio silence...

James and I have visited a bmw master tech tonight. Obviously knows his stuff. He said whatever the issue is, the noise he has heard is not common! He needs to strip some covers etc off and do some diagnostic work with a stethoscope from cold but has narrowed it down to being on the intake side and thinks it could either be an issue with the upper timing chain guide or could be a VANOS hub. The latter being a bigger job as requiring a timing reset when done and quite complex on these apparently (everything is complex to me)...

Can't believe this is the start of Z4 ownership. :o the sun has been out too!

On a separate note, James has been nothing but a gent about the whole caper... He has spent more time on the car since my ownership than in the entire three years it was his apparently... He will be going to heaven it seems!

Saga continues...
 
Thanks for the update Cooky, for what it's worth the VANOS on the N52 is much simpler and easier to work on than the likes of the M cars, so hopefully not too expensive either way.
 
Hi peeps. So in essence, help needed here from any master techs or those in the know. Issue still yet to be resolved. Summary as follows:

2.5si
59k miles
Engine sounds normal on start up when cold
Tickover is perfect - no hunting
Engine sounds and runs normal when temp up
Noise appears when engine properly warm only, but temp gauge still in middle but:
No noise at idle
Noise appears at about 1500-1800 rpm
Is there when the car is being driven through revs
Goes away at idle again

Anybody have any ideas?

Clearly it’s intermittent, putting off a few from looking at it.

And having just bought the car I don’t really want to leave an open cheque book for whoever does look at it!

Please help.

Depressed Z4 owner! :(
 
Did the master BMW tech guy confirm it wasn't timing chain or VANOS related then? Tried it with the serp belt off yet?
 
No. That is what the master tech was guessing at pre proper diagnostic checks etc...

Just re-stating what is happening in case somebody on here has an idea based on the description summarised...

:?
 
I should think a fubard chain/tensioner would be noisy over a much wider rpm range than that, as previously mentioned I'd run it up with the ancillary belt removed & have another listen.
Rob
 
I know it sounds weird, but check the heatsheilds underneath, by the side skirts. These can come loose and produce a rattle when revved.
 
Thanks for the responses. Running it somewhere tomorrow for a further opinion.

James checked the heat shields on Saturday when on a ramp - all seemed fine...

Will see what happens over the weekend. :|
 
Just an update for those interested.

Called into specialist in Kings Lynn (recommendation) and he said it was not a noise / issue he had come across in his time. Used a listening stick and thought it was coming from the timing chain area but couldn't be sure without opening it up. Too busy though and some big jobs booked in so not able to help,

Went to another recommended old school but very experienced mechanic familiar with BMW's. Also thought it sounded like timing chain but again difficult to say without opening it up.. Suggested fitting a timing chain tensioner. Done, but noise still there although he thinks there has been a subtle change in the noise and when it appears. The old tensioner was weak in comparison to the new...

James is adamant this noise was not there previously, but he did change the oil and filter only a couple of weeks before I bought the car. He also replaced the Miller filter with a genuine BMW dealer item last weekend again, but the noise is still there.

What oil filter related areas could be causing this? Seal, housing unit, release valve (bearing sitting under the filter or similar) etc? You can't miss the noise so I believe it must have literally appeared as James suggests...

Castrol magnatec 5-30 fully synthetic BMW approved oil was used...

HELP! PLEASE! :headbang:
 
Hi all.

Still no resolution to this. Car is being investigated tomorrow so hopefully they will find out what the problem is...

Any thoughts from forum members appreciated prior to commencement of work tomorrow....

Cheers.
 
Probably discounted earlier in this thread but how about serpentine belt tensioner or alternator etc bearing.
 
Mike6 said:
Probably discounted earlier in this thread but how about serpentine belt tensioner or alternator etc bearing.

Its already been suggested to run the car up with the belt disconnected for exactly those reasons Mike :thumbsup:
Rob
 
Cheers guys. The noise (video early on in thread) only occurs when the engine is properly warmed up - i.e. No noise initially when gauge up to temperature, only when the car is thoroughly warm (but still in the middle of the gauge) so can't understand why that would be...?
 
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