Knocking Sound, AC System?

[armozo]

Hi all, I just noticed something that now that is hot was a bit easier to pinpoint. I say pinpoint but am looking for the group wisdom.

I hear a knocking sound that diminishes when the AC is turned on. I think it is louder with it off though.
Facing the engine I hear it coming from the right side of the engine. Could it be my air compressor failing?

My car MY10 LR4 has had the timing guides, chain tensioner replaced. I am sure that is not where the sound is generated.

Thank in advance for your insight.

 

[ktm525]

fan clutch?

 

[armozo]

ktm525, it might be... my fan clutch was making clicking noise this winter. I did not think that its issue could exhibit also as a knocking. I think I need to fix the fan first and rule that out.

 

[ktm525]

Ok if you know the clock cadence ticking of the clutch fan then that is not it. Deep knock? Can you record it?

 

[ryanjl]

Yeah, to me, the clutch fan sounds more like a "tink, tink, tink" and less of a knock, if that makes sense. At least in my experience.

It could be either a compressor or one of the belt pulleys going out.

Does it sound external to the engine or internal?

 

[armozo]

The "knock" sounds deep, like knocking on a table ... I cannot say it is external or internal... I can't make it out.
I also have heard and had the "tink, tink, tink" from the Fan.
I will try to record a sample of it.