Disco 1 3.9 V8 engine whine

Hi guys,

Just got my new disco home. Prev owner said it started to overheat slightly on longer journeys, got it back changed t-stat, will flush rad etc see if it makes a difference.

However, big whine coming from the belt somewhere. Seems to me like it could be the tensioner or the fan. I have taken the belt off and turned the fan and tensioner- tensioner seems fine, no play, no apparent noise when I turn it.
Fan- again no apparent noise, i don't know what it is meant to feel like but with the belt off there is a little slip when turning it and you can't push it and it will freewheel if you stop turning the fan it stops, strange similie but it takes as much effort to turn as closing one of those clever quiet shut kitchen drawer things.

Any advice or things i should check before i go and order a new tensioner and viscous fan? Nothing else seems amiss, exhaust pumps out a little more white gas than I seem to remember on my last one. Only other issue is bad idle/stall/hesitant to rev but I am sure that would be a plenum issue having had the same issue on my last v8

Cheers

Just an quick add on- It defo sounds like bearing whine and is coming from tensioner/ alternator/ fan area. I have the one piece serpentine belt with no air con

Well you have mentioned three and discounted two, so what's left? alternator and maybe the power steering pump, the alternator is the one I'd go for, it has a whine of sorts that is from its fan maybe, but with the bonnet closed u shouldn't hear it.
Also replace the belt they don't cost much and easy to replace.
A idle the loudest thing u should hear with the bonnet open will be the viscous fan roar with the belt wizzing around plus the click of the injectors opening/closing.
Maybe u do have a worn bearing, all the revolving parts have them.

Hi,

Mine whined when I got it. There were two causes.

Try running it without the belt (only quickly) to confirm it is something being driven by the belt.

Mine was the alternator and also the idle control valve was whistling, the cause was a leak on the inlet plenum.

Cheers guys!

It's loud enough to gear from inside the car and on revving it gets louder, it did quieten down a little once the engine had warmed up.

I will do some more checks tomorrow

An update on progress-
After much testing and beard scratching, I changed the tensioner. It was well past it! But, noise still there- now I defo know it is the alternator so I will have to start saving some pennies up! Thinking of getting the uprated 120A unit to run my gizmos off

Still bemused that 8 couldn't hear any problems with the spanner technique considering how bad my tensioner was on removal! Ah well!