Loud whine low power - sudden

Hi all, sorry to be a bother again.

Had a bit of a disaster with the disco 2. Early td5 engine, auto box. Set off the other day and it was lacking power, had previously been driving spot on.

A very loud whine presented above around 30mph. Sounds to be coming from drivers side front and gets louder as engine speed increases. It is really very loud. Best way i can describe it is a whine with something mechanical behind it, but no grind. Almost like a jet engine or industrial washing machine sound, but different its hard to describe tbh. Sounds like its close to the bulkhead but hard to pinpoint

Pulled over and checked the front axle fluid, was a little low but nothing major so topped it off. Revved the engine hard with the car stationary and no bad sounds at all. Decided likely the alternator under load. Carried on to see what happens.

Got onto a bigger road and tried to push it a bit to get a better idea of what was going on. Couldn't get it far above 40mph on a flat, serious lack of power on the slopes. Noise didn't get any worse, very consistent.

Im not sure if it managed to get into 4th, i didnt feel a shift but may have missed it.

Took it down hill, driving hard, still struggled i think it capped at around 50mph. Thinking transmission or drive line issues i put the auto box in neutral, all noise went away and coasted fine.

Seemed to be inline with engine speed not movement speed though. Plus it went from fine to terrible overnight. That and the lack of power have left me chasing non driveline issues for now. Im really not sure on this one though, bit disappointed in myself tbh.

Today Ive checked a few extra bits ill briefly go over:
- intercooler hoses, they have signs of wear and age but no clear hole or split.
- fuel pump is making a bit more noise than usual at the filter head, sounds like a little air or maybe a blockage
-stethoscope on various engine parts looking for any off noises, nothing new (crank pulley makes noise, but has for a while so not the issue)
-took the aux belt off and checked the rotation on the alternator, seemed smooth enough probably ok
-visual check of front hubs and axle, nothing apparent

Before i go further, anyone have any insight / ideas on this one?

Thanks for reading

Turbo buggered

Ohh i hope it is. That's fixable.

Seemed in good order when last check, i will take another look. Would show as a stiff or probably seized rotor correct?

Thank you

Just checked the turbo rotor and its nice and smooth.

The wastegate is a little stiff, freed up easily but isnt what i would call a free action. its a little jerky.

Would that be inline with this level of problem?

edit: i recall i bypassed the wastegate control after it started hopping around 6 months back, perhaps a precursor
edit2: asked the passenger and we are both sure the noise was on the drivers side, i guess the sound could travel through the hose though?

I once had a damaged turbo vane on the exhaust side that gave both a high pitch whine and a drop in power,

Righto, ill start looking for used items hopefully something decent shows up nearby. Cheers for the advice!

I wont rush to it though, on the off chance someone chips in with an opposing idea. Main reason is the sound isn't what ive heard on other turbo failures, its more whine and less whistle/woosh/grind - if that makes sense. No smoke either. Full well believe it could be the turbo here.

To listen to, It almost sounds like fluids are involved rather than just air, hence i had been worried about transmission or driveline and kinda still am.

Oil pickup had crossed my mind, but again power drop. I was rather hoping it might be the fuel cooler or something fuel delivery related as its all fitted down that side. Air through fluids would maybe fit the noise. The turbo does make sense with the low power etc, just not the type of noise or location i would expect. Not that it makes me correct at all.

i guess im also trying to ask, is a transmission/axle fault unlikely here given it gets louder with engine speed? From what i understand it's ruled out?

When you had the aux belt off - did you check the PS pump ? or the ACE pump if you have ACE ?

What about the AT oil level ? - TB oil level ? ....

no ace, ps & ac are present. everything on the belt seemed fine turned over by hand.

We have gone through 2 alternators in the past year, so it could have an issue thats not showing when turned by hand. First unit was original, second was cheap crap from ebay, third was i think a bosch item (branded oe unit). I think this was caused by free play in the crank pulley which is still not resolved (local garage wont fit it). I cant rule out it being at fault, but it would be very rapid failure if it has. To note, ill be replacing the crank pulley myself while the car is broken, just a pig of a job.

AT & TB levels not checked actually, bit of an oversight, ill put that on tomorrows list. Well caught, should have been my first check. Cheers!

2 alternators in the past year?

kermit_rr said:

2 alternators in the past year?

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Yea >< Either cheap crap, or i suspect the crank pulley caused it. When the crank pulley fails it gets rotational play and causes a chatter/slap, could cause problems with the alternator internals is my best guess.

Been trying for months to get someone to fit it as it requires a custom tool to lock the pulley out. Didnt have the will to do it through winter but have the time now.

Hi

Im just mid way checking things over again. Found the alternator is giving off a bit more noise than it should, though its only subtle at idle there is a bit of a whine from the area the oil feed pipes go in. The stethoscope picks up a slight grind sound, but its hard to pick up on with the crank pulley also making noise.

I cant get it to make the 'big' noise while stationary in neutral just by gassing it. Im thinking to take it for a quick spin with the belt off but have obvious reservations. Im not sure how far i can go without the coolant pump or charging system. Leads me to a couple of questions again.

Should the alternator go into a state of full charge/load while stationary? Or would i need to drive it?
Same question with the turbo really.

I could do with replicating the situation without risking a breakdown, any ideas very welcome!

Im going to check the auto box and tbox fluids next, just wanted to throw this one out there in the hopes i can isolate the noise this evening

Autobox seemed correct level wise but dark. Nothing unusual really. 115k miles so its probably been done at some point with the filter service. Transfer box over filled and Pretty dark. Drained some off for now but does want swapping if it gets back on the road.

blisco said:

Autobox seemed correct level wise but dark. Nothing unusual really. 115k miles so its probably been done at some point with the filter service. Transfer box over filled and Pretty dark. Drained some off for now but does want swapping if it gets back on the road.

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If????????

Yea, these early d2's don't hold any real value like other old landy's. Money is tight, it needs more work than is mentioned here, wants a quarter chassis & sills amongst other crap jobs i would only do if it had a decent motor. Full service due, hubs want attention. It's not like it's my old 300tdi truck cab or something, that was always worth fixing.

Had issues finding a reliable garage for diagnostics, have no nanocom. If i cant pin down a fault via manual methods no part will be bought, and it will likely get broken, used as a donor vehicle when the tax runs out, or driven to destruction. See i could just weld my van and use that, i need a vehicle for work so time is somewhat limited. The price of a turbo would buy a mig set, i know the welding will work.

I could easily replace the turbo and find i really need a to fit a new front diff, or that the alternator has failed due to an oil feed issue (its an 03). From reading, my symptoms could fit any of those. Its not the best time financially to be self employed Probably is the turbo but without tracing an actual fault, well...

Last sound i had like this one was a transmission fault (bmw e30, getrag box). Opened up said gearbox and found a split roller bearing, replaced it and luckily it was fine thereafter. Was a unique sound and easy to notice from the tunnel. very much like this noise. whirring with like a liquid sound behind it, came out of nowhere. VVVVVVV. Last turbo i had a failure on was more of a whistling, whooshing kind of screech, until it eventually seized, then it just lacked power (no noise).

Just a thought, the mot spot jacked the drivers side front hub to access the arch, hubs not in the best order. The noise is emitting that side. Is there a roller bearing in the axle on a disco? Thinking maybe at the end of the half shaft. Only familiar with the defender tdi axle

blisco said:

Last sound i had like this one was a transmission fault (bmw e30, getrag box). Opened up said gearbox and found a split roller bearing, replaced it and luckily it was fine thereafter. Was a unique sound and easy to notice from the tunnel. very much like this noise. whirring with like a liquid sound behind it, came out of nowhere. VVVVVVV. Last turbo i had a failure on was more of a whistling, whooshing kind of screech, until it eventually seized, then it just lacked power (no noise).

Just a thought, the mot spot jacked the drivers side front hub to access the arch, hubs not in the best order. The noise is emitting that side. Is there a roller bearing in the axle on a disco? Thinking maybe at the end of the half shaft. Only familiar with the defender tdi axle

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I think if the hub had a bearing that was up the spout that would show with the three amigos. Here is what it is, though you'd buy the hub as a whole.
https://www.bearings-online.co.uk/i...MI3eDNqO-R8QIV2cPVCh3hTgDJEAQYASABEgKI9fD_BwE

Apart from the CV joint, there is nothing between it and the diff, bearing wise.