Engine Idle Noise 3.0i Pre facelift Updated Pg 3

[ronk]

i'd be very concerned if big end bearings were the reason for everyone having this sound.

i can understand why in your case they have failed, oil pump failure would cause oil starvation and it takes all of about 30 seconds with no oil feed to kill bearings.

depending on how much damage was done would effect the cost of the repair; but, i would estimate something like £700-1000 for a new crankshaft, bearing kit and fitting.

the noise in the videos does not sound like big end failure, it sounds like a worn roller bearing as suggested, something like P/S pump.

i'd be interested to have a look for myself, i'll check over mine see if its just something i've not noticed.

Ry

I don't think it a bottom end noise either - when that happens there is a very distinct noise and a noticible lack of oil pressure!

You will see however that in DaveRoms case - a new oil pump and bearings on 1 & 6 seem to have cured his problem.

I see the BMW Tech Guru on the 15th Dec - watch this space eh?

 

[Mr Whippy]

Any kind of big end bearing wear you can hear, I would imagine, would propogate into bearing failure fairly quickly.

Also, big end bearing wear tends to get louder the faster you rev the engine. If you can hear it at idle, it'd sound like someone hitting the block with 100 hammers at 5000rpm+!

There may be something else to do with the big end bearings though, but can't think what...

I think it's probably just something else (ie, the oil pump), but they did those bearings as they looked a bit worn!?

Dave

 

[Beancounter1980]

http://www.z4-forum.com/forum/viewtopic.php?f=3&t=15023

 

[ronk]

It goes into my local dealer to see the visiting BMW Guru on tuesday 15th - I'll post the verdict asap!

 

[ronk]

The BMW Guru says "it's a bit of chatter on the vanos" he says that it's not at a level to be repaired/replaced under the approved used car warranty. Mine he says, is one of the quieter one he's heard.

I'm a bit unimpressed really and its certainly knocked the shine off an otherwise lovley car. At this point in time, I could not put my heart into another BMW.

 

[Mr Whippy]

Vanos chatter?

As in the helical gears on the cam shaft fronts that alter the phasing are chattering? That is the only moving/wear element that reciprocates on Vanos.

Wasn't this noise from the bottom of the engine, at the front, not the top-front?

Dave

 

[ronk]

Vanos chatter?

As in the helical gears on the cam shaft fronts that alter the phasing are chattering? That is the only moving/wear element that reciprocates on Vanos.

Wasn't this noise from the bottom of the engine, at the front, not the top-front?

Dave

In a nutshell yes!
The explanation given by the service manager was the helical / bendix gear shaft thing. He assured me than nothing was going to let loose.

The noise is at the front of the engine but very difficult to pinpoint with any certainty. I'm sure it is being transmitted all over the place.
When the car is horizontal or nose up - Rattle Nose down - little or nothing.

As you can gather, I'm not impressed!

 

[czechT698]

pff they always say Vanos :x All I know is that i gave mine a good 3 minute revving on 3000rm with clutch pressed and the noise got little better. Might be lifters??? :? Try it you have nothing to loose....


http://www.meeknet.co.uk/E38/Tappets.htm

 

[Mr Whippy]

Have you tried just unplugging the DISA unit on the manifold.

My top-end sounded like it was running with loose nuts and bolts in the head, when uplugged it literally went what sounded like over twice as quiet.

Replaced the DISA and it fixed it.

Worth a quick check anyway

Dave

 

[ronk]

Have you tried just unplugging the DISA unit on the manifold.

My top-end sounded like it was running with loose nuts and bolts in the head, when uplugged it literally went what sounded like over twice as quiet.

Replaced the DISA and it fixed it.

Worth a quick check anyway

Dave

No - but I'll give it a go!
These things are new to me, what am I looking for please?
Thanks

 

[czechT698]

Have you tried just unplugging the DISA unit on the manifold.

My top-end sounded like it was running with loose nuts and bolts in the head, when uplugged it literally went what sounded like over twice as quiet.

Replaced the DISA and it fixed it.

Worth a quick check anyway

Dave

No - but I'll give it a go!
These things are new to me, what am I looking for please?
Thanks

all U need is here :

http://www.z4-forum.com/forum/viewtopic.php?f=30&t=12150

 

[czechT698]

bump... any news??

 

[ronk]

As soon as the snow clears, I'm going to take it for a second opinion.

If I get the same answer I'll rest easy - I'll post just as soon as I know.

I'm not a wimp in the snow but I live at the bottom of a hill and think my Disco is a better bet than the Zed!

 

[czechT698]

same here, I dont drive the Z in the winter, happy to see that this thread is still alive though

 

[DaveRom]

The BMW Guru says "it's a bit of chatter on the vanos" he says that it's not at a level to be repaired/replaced under the approved used car warranty. Mine he says, is one of the quieter one he's heard.

Thats interesting, but i suppose every car is different. I had the vanos unit replaced back in april/may time last year and it made no difference to the engine sound at all.

Its coming upto around 3 months now since i had the car repaired (when they were convinced it was oil pump/bearings) and it's still all ok.

I still have the noise but its really faint. You have to crouch down at the front of the car to hear it.

It's a shame you don't live closer because i'd have let you compare it with mine

 

[czechT698]

So basically oil pump bearings made the noise a little less noticable? Always thought the noise is somehow oil related... Changing from 5W30 to Edge Sport 0W40 made a huge difference for my engine, for a while 80% of all noise went away... interesting...

 

[czechT698]

BUMP... any news on the issue??

 

[czechT698]

www.youtube.com/watch?v=MulqcY3PIdQ

 

[ronk]

I got the BMW guru out to hear the problem - he gave me the line "Oh it jast a bit of chatter on the vanos gears an nothing to worry about" He also declined to rectify it under a BMW used car warranty! It has to break down before they'll deal with the problem he told me.

As a retired engineer, the noise offends!

Look out - the warranty may be good - but its not cast iron good! :thumbsdown:

 

[czechT698]

That person apparently has no clue to what hes talking about, I put my ear on the engine vanos everal times and that thing purrs like a cat. I am starting to suspect it might be the crankshaft bearings after all... No warranty here, will have to pay cash.