Whiny noise

[DickieO]

Ive started hearing this loud whiny noise coming from my engine bay (2001 GU, 3.0L turbo diesel) but having trouble locating the where its coming from or what it might be.

It started happening one morning after i may of turned her off too quickly the day before when i was rushing around for a wedding. The next morning it was super faint as i drove home then loud the next time i started her up in the late arvo.

When idle she sounds fine. When i give it a bit of throttle the sound comes in and gets louder as i rev harder. I havent driven her since noticing the noise as i was scared the turbo was the issue.

I pulled the intake before the turbo to check and the turbo seemed fine. Then started the washing detergent and water trick trying to fine leaks. Only found the one behind the turbo which spews bubbles while idling. Bubbles dont get worse when given revs so im not sure if this is the issue causing the noise.

I have a video and pics and would love some help.

https://goo.gl/photos/QQ6m1UWAy4ySyt6M6
https://goo.gl/photos/P2UYSgTqEXeXf4Ro8
https://goo.gl/photos/kLovkHGtuBZU6aZc7

Cheers
Richard

[MB]

G'day Richard, try a 1.0m or so length of syphon and or garden hose with the end cupped to your ear. Move the other end slowly around suspect areas in the engine bay, should help pinpoint the issue location mate!

[Avo]

look at the studs on the exhaust manifold,i think it is usually the second one at the top,is there blackish soot marks around it,i had a leak on the gu and it sounded very simular,ended up being a gasket but i replaced the manifold aswell as it was warped.(warrenty-for us so the descission was easy)

[DickieO]

Yeah have tried that all around the exhaust and the turbo, tried laying under the car as well but couldnt locate it. Its quite loud youd think i could find it easily but no luck. Just took it for a shoft short drive, no noise at 4psi, then starts to come in at 5psi.

Any ideas?

[Avo]

yep ours would not sound until it reached boost then as you plant it it went louder then stopped.try getting a torch in and have a look at the studs to try and find it

[DickieO]

How much of the exhaust side on the engine bay do i have to pull apart to get a good look at the second top manifold bolt. I can see the first one but with the turbo and and intake plumbing, heat shield below the engine number it doesnt look like there is an easy way to have a look at it.

[Avo]

Maye i dont lnow as i didnt tackle it..i took it to the mechanic and he said it was a common prob and pointed it out as soon as i told him what was going on..try doing what MB saod and poke a hose around to find out were the sound is worse..you can see the bolt but only just

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[Avo]

Hope this pic helps a little the bolt nut is in the circled bit behind both pipes http://www.nissanpatrol.com.au/forums/images/imported/2017/05/165.jpg

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[Col.T]

G'day Ric,
I'm a bit of a dumbo and I'm coming in late but my kweschun is, did you fix that funny bubbly leak before you went further??
Dunno why but I really don't like leaks, regardless of where they are.
Col.

[DickieO]

Thanks for the pics AVO. Im going to have to do some more pulling apart to get to the bottom of where this noise/leak is coming from.

Col.T, i havent even looked at it yet ive been so busy with work. Plan to tackle it all asap.

From what ive been reading i may come across a warped manifold if its not just a gasket leak. So im looking to tear it all down this weekend and get to the bottom of it.

Looking to get the gaskets and any other parts i should need for the job before the weekend rolls over

Can anyone fill me in on what other gaskets or parts i might be needing if tear it back all the way to the manifold trying to find this leak?

[JackCollo]

Hi col
I have a feeling that a leaking intercooler might be the cause of your whining because I currently have the same noise on my 2000 GU II ZD30


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[DickieO]

After tearing her down a bit more i think ive come to find my sooty leak.

Last cyclinder (clisest one to the fire wall)

https://goo.gl/photos/P2UYSgTqEXeXf4Ro8

Im about to pull the manifold off now. Quick questions, is this the sooty deposits i meant to be looking for?

And how do i check for a warped manifold?

Cheers everyone

[Avo]

Nice big straight edge i would think. ..as said before i had mine done under warrenty so not much help

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[BigRAWesty]

You wont be able to check the manifold as its such a small amount.
Pretty sure its the studs that stretch from factory so a good set of aftermarket studs, new manifold and gasket and away you go..
I wouldnt risk skimming the old one and making it thinner..

[threedogs]

Hi col
I have a feeling that a leaking intercooler might be the cause of your whining because I currently have the same noise on my 2000 GU II ZD30


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one of the easier things to check, remove the IC being a 2000 it must be oily they all are.
disconnect the battery remove the IC tape both ends up airtight, introduce some are via a
bike pump or similar you dont need much and submerg in a kiddies pool bath or any thing
of size. a leak should show up straight away, replace it with a fully tigged and tested one
from Ebay Diesel Smart seem to be the fairest going around. If you reinstall the all one just to
get mobile make sure its dry[Hair Dryer] re connect battery

[DickieO]

I placed the manifold on my spirit level and could notice a 0.5 - 0.75mm difference from the front to back, when undoing the manifold nuts i noticed the two back ones where the soot was were so easy to undo nearly no effort was require, the others were reasonably tight.

Luckily none snapped into the head.

I was under the impression machining the manifold was ok? and if its barely noticeable my half a mm difference has me believing I have a pretty seriously warped manifold.

If thats the case, anyone know of quality brands of aftermarket manifolds?

And if I’m replacing the studs for the manifold, whats the best material for exhaust manifold studs and nuts? e.g. mild steel and copper nuts?

[DickieO]

Thanks threedogs, i'll check the intercooler out while i got everything apart and before i put it back together.

Im sure I found my issue being the last cylinder manifold gasket, with it being loose, signs of soot before pulling off the manifold and from looking at the gasket once removed the amount of soot buildup compare to the other 3 was obvious there was a issue there.

[BigRAWesty]

I placed the manifold on my spirit level and could notice a 0.5 - 0.75mm difference from the front to back, when undoing the manifold nuts i noticed the two back ones where the soot was were so easy to undo nearly no effort was require, the others were reasonably tight.

Luckily none snapped into the head.

I was under the impression machining the manifold was ok? and if its barely noticeable my half a mm difference has me believing I have a pretty seriously warped manifold.

If thats the case, anyone know of quality brands of aftermarket manifolds?

And if I’m replacing the studs for the manifold, whats the best material for exhaust manifold studs and nuts? e.g. mild steel and copper nuts?
They come as a kit.
Not sure on brand though..
Pretty sure patrol a part will be able to assist

[threedogs]

Take winnie out of the Patrol oh no sorry read that wrong
no idea what the noise is then doh

[Stropp]

i used to have a whinny noise in my patrol so i divorced her :) sorry off topic a bit .

[DickieO]

I was thinking the girl had all the NADS done but I dont think the EGR blanking plate was ever installed.

Assuming i got this right should the blanking plate be placed where the red one is or the blue one? or both?

72158

[threedogs]

looking from the front of the motor I blocked mine on
the top lhs side,, was a reasonably easy job to do

[DickieO]

Awesome, i'll make a plate up to block it off on the red side.