Turbo Howl - fixed

Ralf*

///Member
ChefDJ said:
But once I rev passed it, even when cold, the sound can go away :dunno:

nope, the howl would go away after a certain airflow speed has been achieved

think of trying to blow a reed flute, there is a very specific intensity to get it to make music, too soft or too hard and it won't produce, similarily the turbo inlet airflow might howl only at a certain combo of airspeed and temperature
 

ChefDJ

///Member
That makes sense. Thanks Ralf. Where around the turbo could I check? The howl sounds like it's coming from right inside or right next to the turbo. All the other pipes and inlets are clean/new.
 

Ralf*

///Member
ChefDJ said:
That makes sense. Thanks Ralf. Where around the turbo could I check? The howl sounds like it'c coming from right inside or right next to the turbo. All the other pipes and inlets are clean/new.

it woudn't be the turbo itself, but rather all the main airflow pipes leading into the turbo inlet, from air filter onwards, check for pipes that might be damaged, crushed, if possible look inside the pipes for obstructions that could cause the air to not flow smoothly, ie sharp bends, nicks, foreign objects.

all these factors could disrupt the smooth airflow, that then impinges on the turbo compressor in a turbulent manner, causing the turbo compressor to cavitate (possible howl)


the distinctive Howl that the Avro Vulcan bomber (UK) makes, is due to an airflow resonation in the air intake as it hits the first stage of the jet engine.
 

ChefDJ

///Member
Busy doing a lot of research now.

I'm stumped.



See this thread:

http://www.bmw-driver.net/forum/showthread.php?t=13687

Hi All,
My 2005 530D has starting making a whistle sound when accelerating, you can hear the turbo spinning loudly from inside the car.
I took off the inlet pipe and can feel some play on the turbos impeller, there is no scraping that I can see and the movement is very slight. I then let the engine idle and can see the impeller rotate freely and no signs of imbalance.

But I have checked everywhere and cannot see any vacum or exhaust leaks and the wastegate seems ok as I can manually move it.

I want to try and remove the turbo to have it checked properly, has anyone done this and can they advise on whats involved, also I am happy to get any feedback on the issue is someone had a similar issue and hopefully it was not the turbo?

Basically car drives ok, but no real solid boost and when accelerating you can hear the turbo spinning and it sounds like its flat out if you rev high, at idle you can hear nothing and with the inlet off the turbo on idle I can see the turbo spinning and it appears ok and no noise, only get it when driving and its very loud, and worring. There is a bit of movement on the spindle but not enough to have the turbo fins hit the wall. also when at crusing speed there is no noise, only during acceleration.

Thanks in advance for all and any help...

No need to take the turbo off to test it, sounds like you have done enough to make sure that the impeller and its bearings are ok.

TBH it sounds like a ripped or cracked intercooler hose or the intercooler itself. Had one a while ago where a stone or similar went through the intercooler and caused the same issues as you are having.

Best ways to check these - ENGINE NOT RUNNING - visually and feel around all the turbo hoses for any rips or holes. Then get down on your knees, look at the intercooler that's behind the lower front grille behind the bumper and look for any holes or cracks. The giveaway sign of an issue with your intercooler is you will see oil stains around the fins of it.

HTH

change your breather filter,i had the same problem when i got the 320 lately and i got it done it solved my noises.

what he said, these breather filter or turbo filters etc are always over looked at service time and not changed, it needs to be changed every 50k or so, i changed mine on my E60 at 59k and the car pulled so much better after doing it, think the part was 70 notes from BMW dealership.
 

ChefDJ

///Member
Right.

Research indicates that the turbo, starved of oil, may cause this "hoover" like noise because of a blocked crankcase/turbo/oil breather. Further research shows that this is not a difficult item to replace.

Apparently the old filter type resembled a toilet roll and would never get changed by BMW. This design was discontinued and BMW introduced a newer "vortex" insert that fits right into the older breather housing.

BMW JSN have one in stock and so I'll be picking it up after work and doing the change immediately. 450 bucks.

Now... Do I need to drain the engine oil first? Logic dictates no, as the filter sits at the top...
 

Mrcloc

New member
ChefDJ said:
It is indeed. The guy says he bought 15 of them 3 years ago and has 2 left which he's battling to move. Says it's an original Garrett GT25 which he used to sell for 9900 ex vat.

13 turbos in 3 years.

Not_bad.jpeg
 

Dhp507

///Member
ChefDJ said:
I'm sort of leaning towards getting a new one fitted at the place in Honeydew called Alpine Turbo. Anybody had experience with them before?


Dhp507 said:
Speak to Stallion Turbos also...........

I thank you. Very much so.

Phoned them...

R5200 incl. VAT for a recon.

R8900 incl. VAT for a new one.

:slow:



Helping where I can......note they do hybrids also....
 

ChefDJ

///Member
Yeah I know, thanks :chef:


I'll see what happens in the morning. Perhaps I've managed to fix it for now.

I changed the crankcase breather and there is definitely a difference is sound, however I let the car idle a while afterwards and then took it for a small test drive. The howl was gone, but like I said, I let it idle first to circulate oil and let it warm up a bit. Though, it should still have done so after what I experienced yesterday. I think I'm okay. I dunno...

Sleepless night ahead?

That breather was clogged to no end. I think that was the first time ever it had been replaced.

:blueCry:
 

Ralf*

///Member
ChefDJ said:
Yeah I know, thanks :chef:


I'll see what happens in the morning. Perhaps I've managed to fix it for now.

I changed the crankcase breather and there is definitely a difference is sound, however I let the car idle a while afterwards and then took it for a small test drive. The howl was gone, but like I said, I let it idle first to circulate oil and let it warm up a bit. Though, it should still have done so after what I experienced yesterday. I think I'm okay. I dunno...

Sleepless night ahead?

That breather was clogged to no end. I think that was the first time ever it had been replaced.

:blueCry:

if this truly worked then...:
1)you saved yourself a massive packet of money
2)you will need to give a DIY write up with some images for us to learn
3)a massive well done
 

Kish2604

Administrator
Staff member
Chef! You need to have a once over from Cois for this massive oversight! How have you not had the most important piece of maintaince on the diesels not done?

Anyways... Glad you getting somewhere:=):
 

anton-sa

Active member
ChefDJ said:
Yeah I know, thanks :chef:


I'll see what happens in the morning. Perhaps I've managed to fix it for now.

I changed the crankcase breather and there is definitely a difference is sound, however I let the car idle a while afterwards and then took it for a small test drive. The howl was gone, but like I said, I let it idle first to circulate oil and let it warm up a bit. Though, it should still have done so after what I experienced yesterday. I think I'm okay. I dunno...

Sleepless night ahead?

That breather was clogged to no end. I think that was the first time ever it had been replaced.

:blueCry:

Now take a "breather" and try and get a good nights sleep... :roflol::clapper:
 

ChefDJ

///Member
Kish2604 said:
Chef! You need to have a once over from Cois for this massive oversight! How have you not had the most important piece of maintaince on the diesels not done?

Anyways... Glad you getting somewhere:=):

I thought it had to be done by a specialist :facepalm:

And BMW never did it either. I blame them. The #&@¥$.
 
Top