Kia Diesel engine knock/tap

[Benxkr]

Hi. I have a tapping noise on my Kia Sportage 2l diesel. I’ve changed the hydraulic tappets, substituted each injector with a spare one but can’t sus out where the noise is coming from.
(Please see video) https://youtu.be/mNEVaN2ALEI
It’s been doing it for a couple of hundred miles and doesn’t affect performance
Thanks for reading

[GreenV8S]

A leaking exhaust manifold can produce a very mechanical sounding tap.

[Benxkr]

I will check again, but I’ve already replaced the exhaust manifold along with the turbo

[GreenV8S]

It sounds as if this vehicle has an unusual history that you haven't told us about. When/why were the exhaust and turbo replaced? When and why were the tappets replaced? Did either of these works precede the noises you're describing here/

[Benxkr]

I will check again, but I’ve already replaced the exhaust manifold along with the turbo

[Benxkr]

Hi. I bought the car with the tapping noise with the intention of fixing it, thinking it was a simple job. Flushed engine, fresh oil and filter, new hydraulic tappets, still no joy. Then the turbo blew so replaced that. Substituted injectors one by one and the tapping is still there. Don’t know what else to try and it’s too good to scrap

[E-bmw]

Benxkr said:

Hi. I bought the car with the tapping noise

That is a bit different to "been doing it for a few hundred miles".

Personally, I just think it sounds like a diesel engine...... Oh, it is

[Benxkr]

I’ve been using it as it runs well but a diesel shouldn’t tap like that

[GreenV8S]

Benxkr said:

can’t sus out where the noise is coming from

A mechanic's stethoscope can be a great help tracking down mechanical noises. That video makes it sound as if the tapping as at engine speed so it's probably coming from the engine itself rather than an ancillary. The stethoscope would confirm that and give you some idea which area of the engine it's coming from.

[Benxkr]

Thanks Greenv8s. I’ll get hold of a stethoscope

[Oscar011]

Timing chain?

[Benxkr]

It’s a timing belt

[E-bmw]

Benxkr said:

a diesel shouldn’t tap like that

I take it you have never been within 100 yards of a Nissan Patrol diesel with the bonnet up then........

[Benxkr]

I can’t say I have

[paintman]

Not familiar with the engine but as you mention hydraulic tappets & I AM familiar with those on the RV8 did you change the camshaft at the same time?
If you don't change both on the RV8 you'll likely keep the problem as they wear together plus the old part will rapidly damage the new.

An exhaust manifold blow can sound EXACTLY like a worn tappet & whilst I appreciate you say you've fitted a new exhaust manifold are you absolutely sure that the mating surfaces of manifold & head are true & that any gasket is sealing correctly? Might be worth taking it off to see if there any telltale black marks on the gasket - although this might mean fitting a new one.

Edited by paintman on Saturday 15th December 10:21

[Benxkr]

Thanks Paintman, I’ll check it out