300tdi Defender ticking noise (not from engine bay)

Hello,

I’m hoping someone can help, I’ve looked at other threads regarding ticking, but they all seem to be from the engine.

I have a 300tdi Defender 110, it has recently started making a ticking noise, it only happens once she has warmed up and it is in time with the engine speed.

Open the bonnet and I can’t hear any ticking, go underneath and the ticking is very clear around the transfer box area, mainly on the drivers side.

I have already checked for exhaust leaks and it’s not that, any suggestions?

Many thanks,

Jon.

does it go away when you depress the clutch? could be clutch release bearing

TorsionBhudda said:

does it go away when you depress the clutch? could be clutch release bearing

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No change when the clutch is in or out, it’s more of a blowing tick than a mechanical tick, if that makes sense? I would say a leaking gasket, but there’s no noise in or near the engine bay.

Try holding hand over exhaust tailpipe to block it (Short time only) whilst someone listens for leak from exhaust system. Also check all air intake connections are also secure could be air being drawn in from a loose intake pipe.

Could be exh manifold gasket or head gasket at back of engine

TorsionBhudda said:

Try holding hand over exhaust tailpipe to block it (Short time only) whilst someone listens for leak from exhaust system. Also check all air intake connections are also secure could be air being drawn in from a loose intake pipe.

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Hi,

Check this and it’s definitely not an exhaust in intake leak.

Also seems odd that it only happens a once warm and disappears after around 2-4mins of tickover warm down.

Kev12 said:

Could be exh manifold gasket or head gasket at back of engine

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Hi,

I have replaced the manifold gasket as I recently rebuild the turbo and cleaned the intake etc. (ticking was happening before this work was carried out). There’s no ticking anywhere near the engine, so I don’t think it would be the head gasket..

It's possible theres a crack that only becomes obvious due to the thermal expansion of the metal as it gets hot. May also be a bearing being effected and becoming noisy as it gets hot.
The old school way to check things would be long screw driver place the blade on certain areas i.e lift pump,vacuam pump,Transfer box etc and your ear to the handle it should then become obvious where the noise is coming from.

TorsionBhudda said:

It's possible theres a crack that only becomes obvious due to the thermal expansion of the metal as it gets hot. May also be a bearing being effected and becoming noisy as it gets hot.
The old school way to check things would be long screw driver place the blade on certain areas i.e lift pump,vacuam pump,Transfer box etc and your ear to the handle it should then become obvious where the noise is coming from.

Click to expand...

Thanks, I’ll give this ago once my ramp becomes available! I think I have a stethoscope somewhere as well.. I had another listen last night and it’s most obvious if I stick my head up between the right hand side chassis rail around the middle of the vehicle, so top rear of the transfer box area.

TorsionBhudda said:

https://forums.lr4x4.com/topic/80113-300-tdi-ticking/

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Thanks, already read that one and panicked about the outcome he had! Doesn't match up with the noise not coming from the engine though?

Brief update - I managed to get on the ramp for a closer look. Typically, it wasn’t ticking whilst on the ramp, I only get around 4mins until the ticking stops. I tried reving the engine and holding a steady RPM but it wouldn’t come back.
I took a look around the suspect area, but all appeared fine.

On the way home I found a large lay-by and managed to get underneath whilst it was still ticking. It’s definitely loudest towards the rear of the vehicle, but I can feel and hear (holding my ear to) a ticking on the drivers side chassis rail.

Still nothing noticeable in the engine bay.