Whistling.

[Simon_CSK]

My D2 TD5 has develpoed a bad whislte/whine under load. 

I suspect either the front axle or the gearbox any help appreciated. 

[JohnnoK]

You may have a leaking turbo hose to or from the intercooler. The hoses sometimes get pinhole leaks or the clamps aren't tightened properly.

 

[Snagger]

My thoughts exactly.

[miketomcat]

Gearboxes tend to whine. But try knocking it out of gear both main box and transfer box one at a time whilst rolling along. Also go through the gears with in transfer box neutral.

Mike

[FridgeFreezer]

Whistle/whine I'd suggest turbo boost leak, alternator, or PAS pump.

The alternator on the ambulance whines quite loudly if the split-charge switches in with a very low 2nd battery.

[Simon_CSK]

1 hour ago, JohnnoK said:

You may have a leaking turbo hose to or from the intercooler. The hoses sometimes get pinhole leaks or the clamps aren't tightened properly.

 

Just replaced a leaking hose.

That was my first thought.

[JohnnoK]

21 hours ago, Simon_CSK said:

Just replaced a leaking hose.

Recheck your clamps.

[landroversforever]

As it’s a TD5.... I think the manifolds whistle when they’ve warped?

[Blanco]

Prime suspect would be turbo noise, sounds a bit silly but stick your head out of the open window while driving (better still while someone else is), you won't mistake it if it is the turbo. And assuming it is then the first thing to check will be the manifold. If it is the manifold then there is quite a bit on here and elsewhere about why they warp and removing webs etc. not to mention changing the studs for something better. I prepped a secondhand one ready to fit prior to stripping mine down, unless you have a mill or a shop close by it saves time.

 

[SteveG]

12 hours ago, landroversforever said:

As it’s a TD5.... I think the manifolds whistle when they’ve warped?

Most likely this.  Waiting for Neil to add his thoughts too 😉

 

[Simon_CSK]

Some developments today. I drove through a few big puddles and the sound stopped for some time. I am now thinking something driven by the fan belt. 

The turbo on the car has been replaced twice.

[Sabre]

When my 300TDi D1 started whisteling suddenly one day, the problem was a leaking intercooler tube. Had a crack right at the bottom where the tubes go into the bottom chamber

[Tanuki]

Saying it stops after traversing a watersplash makes me think you should check your serpent.

I've seen a few instances [generally presenting with alternator-charge issues in applications where there's a twin-battery setup and some serious electrical loads] where the serpent's drive-surface has become polished and - more importantly - the little grooves in the pulleys have become fillled with belt-wear debris/rust/mud so the little peaks on the belt can't settle all the way down into the grooves - meaning grip is compromised and you get poor charge/nasty-noises.

A good indication of this is a brief 'twitter' noise when you turn the engine off.

Answer: fit a new serpent [Gates/Dayco being the brands to go for] and vigorously wire-brush the pulleys to remove any clag from the grooves.

[Blanco]

Also check the tensioner idler, mine seized solid while driving and threw the belt off, its a sealed bearing that has a limited lifespan, usually more screech than whistle though?

[Simon_CSK]

On 10/20/2019 at 12:37 PM, Blanco said:

Also check the tensioner idler, mine seized solid while driving and threw the belt off, its a sealed bearing that has a limited lifespan, usually more screech than whistle though?

That sounds about right