300tdi/r380 110 - squeaking noise from bell housing.

[Oberon 110]

Hi all,
So I've already posted two threads trying to diagnose a squeaking and occasionally rattling noise coming from somewhere behind the firewall of my 110. The squeaking is only when in motion and accelerating and is related to RPM - goes away at high RPM and when letting off the throttle. I'm quite sure it's not the front drive belts, as it absolutely only happens when in motion and accelerating.

After more looking around under the car, I've established the following:
- The front driveshaft UJs are not as good as I first thought - diff end is ok, but the t/case end has a small amount of play.
- The power steering box has a bit of backlash on the input side/steering column UJs that isn't translated to the drop arm. Not sure if this could be at all related.
- Track rod ball joints need replacing but I'm sure this isn't relevant.

And the main symptom:
- When rotating the front drive shaft back and foward (with the vehicle on the ground, in gear, hand brake on - so just wiggling the shaft within it's backlash), a slight squeak can be heard from the bell housing. I was pretty exhaustive locating the source of the squeak when doing this, and I'm quite certain it's coming from inside the bell housing.

My own thoughts are clutch being on the way out - specifically the bearing arm failure that I'm aware is common - hoping it's not something terrible like excessive crankshaft end float or gear box input shaft issues (I do have a slight chatter on the input shaft at idle - my LR specialist isn't concerned about it).

Bit of a long one, hopefully it all makes sense, and I'll be greatly apprecaitive of any thoughts! Cheers guys

[workingonit]

Hi all,
The squeaking is only when in motion and accelerating and is related to RPM - goes away at high RPM and when letting off the throttle.

- The front driveshaft UJs are not as good as I first thought
- The power steering box has a bit of backlash on the input side/steering column UJs that isn't translated to the drop arm. Not sure if this could be at all related.
- Track rod ball joints need replacing but I'm sure this isn't relevant.

And the main symptom:
- When rotating the front drive shaft ... I was pretty exhaustive locating the source of the squeak when doing this, and I'm quite certain it's coming from inside the bell housing.

My own thoughts are clutch being on the way out - specifically the bearing arm failure that I'm aware is common - hoping it's not something terrible like excessive crankshaft end float or gear box input shaft issues (I do have a slight chatter on the input shaft at idle - my LR specialist isn't concerned about it).

Don't have any answers, just questions. Sounds like you a have few obvious things to fix first to eliminate them as a cause. Inclination to think from your description either front uni or squealing is clutch thruster bearing with no lubrication or the rattle is deteriorating arrangement of bearings/cages/housing. Any noise from the clutch thruster bearing (on the arm) when you change gears? Are you able to change gears easily and can you stall or do you get slip. Going through really muddy conditions with no wading plugs might contaminate the thrust bearing and wear seals. Are your engine and gearbox mounts in good condition - I've run for a while (months) on 3 out of four broken on a Disco1, some rattling at low revs then settles at speed.

[TonyC]

If you rest you foot lightly on the clutch when driving, does the noise change?

Tony

[Blknight.aus]

check your bell housing bolts...

Just fixed a "squeeking" generator, the mounting bolts between the engine and alternator were loose and the squeeking was the ally casing of the alternator vibrating on the steel of the motor.

Probably not it but worth a look.

[Oberon 110]

If you rest you foot lightly on the clutch when driving, does the noise change?

Tony
I'll give this a crack, oddly enough the noise hasn't occured since I posted... makes me wonder if it is the throwout bearing/arm, and with all the rain in SEQ a bit of oily water has gotten up in the bellhousing providing just enough lubrication to stop the squeak.

[Oberon 110]

check your bell housing bolts...

Just fixed a "squeeking" generator, the mounting bolts between the engine and alternator were loose and the squeeking was the ally casing of the alternator vibrating on the steel of the motor.

Probably not it but worth a look.
Cheers! Yep, easy enough to make sure those bolts are properly snug

[Oberon 110]

Don't have any answers, just questions. Sounds like you a have few obvious things to fix first to eliminate them as a cause. Inclination to think from your description either front uni or squealing is clutch thruster bearing with no lubrication or the rattle is deteriorating arrangement of bearings/cages/housing. Any noise from the clutch thruster bearing (on the arm) when you change gears? Are you able to change gears easily and can you stall or do you get slip. Going through really muddy conditions with no wading plugs might contaminate the thrust bearing and wear seals. Are your engine and gearbox mounts in good condition - I've run for a while (months) on 3 out of four broken on a Disco1, some rattling at low revs then settles at speed.
No troubles changing gears and no noise when I do, and doesn't seem to be any slip when stalling intentionally. Motor and gear box mounts look good. I think you're on the money with thrust bearing/arm and general clutch wear causing rattles.

Upon closer inspection the front unis are ok I think - backlash on the t/case output made it look a bit worse to me.

Appreciate your response mate!