XC90 56 plate d5 Ticking when hot.

[Danjwilko]

Hello all

First problem I've not managed to solve myself as I'm not 100% what it actually is, as title says I have a loudish ticking noise when hot,

It's pretty much instant startup on turn of the key, runs smooth as a nut.

When cold it's pretty quiet if I'm honest, just has bit of a oil smell after a while if it's sat idling gearbox oil I believe but same as a new bottle so don't know if it's going to need changing, however that's another story.

I've carried out the injector test via the dice/Vida and it was pretty close to perfect less than +/-0.2 iirc on all 5 cylinders.

It did it before the oil change so I thought I'd change it and see if it sorted the noise, as it had done 8k since it's last service of which I'd done 6k of, this quietened the engine down no end on idle and running however this ticking remains only once hot.

I was led to believe it may have been the injectors hence the test with dice, however with previous experience of the injectors it's a lot louder and slower than this almost sounds like worn out tappets Il post a video if possible.

Any insight would be brilliant, or if anyone knows what it is from the symptoms then even better.

[cheshired5]

You have a 2006 model year so dodgy hydraulic tappets is the most likely.

[Danjwilko]

Great trust me to pick a dodgy year, didn't realise they had tappet issues if I'm honest, Would I be looking at replacing anything else while I'm at it? Rocker arms? I should have a read up really.

https://youtu.be/drUhdXvD-Yo

Quick video link it's nowhere near as loud in the video as in person so hopefully you can hear what I mean.

[PSJ 63]

I've been using liqi moly engine cleaner over the last couple of services and found that the tappets on my 55 plate have quieten down , it may be worth a try before more serious measures.

[paddy74]

You can use two-stroke oil together with the fuel. Works like a charme, and is way cheaper than additives. I am using 125ml for one full tank of fuel.

[Danjwilko]

Cheers guys
Il have a look into the liqimoly think I've heard of it being used before, different vehicle same principle.

Not sure on the 2 stroke oil not come across that but you live and learn ,however Il have a read up and see what's what, if it's going to help then I'm all for it, the only bit I don't understand one of the cars we have in the family had worn out hydraulic tappets which you heard them as soon as you started the car so this one threw me as it's not doing it all the time

[cheshired5]

Originally Posted by paddy74

You can use two-stroke oil together with the fuel. Works like a charme, and is way cheaper than additives. I am using 125ml for one full tank of fuel.

I use a 1:200 ratio so 350ml per 70 litre tank of diesel in my Euro 3. You can use the same ratio on Euro 4 but maybe only do it every 4 tanks due to the DPF.
Two stroke in fuel is for quieter injectors though and won't have any effect on tappets which are cared for by the oil system.

[cheshired5]

Originally Posted by Danjwilko

Great trust me to pick a dodgy year, didn't realise they had tappet issues if I'm honest, Would I be looking at replacing anything else while I'm at it? Rocker arms?

Yes it's rockers and lifters. I say tappets as a generic term for the noise that people are familiar with.
A member in this thread has recently done the job so perhaps have a word with him.

[paddy74]

Originally Posted by cheshired5

I use a 1:200 ratio so 350ml per 70 litre tank of diesel in my Euro 3. You can use the same ratio on Euro 4 but maybe only do it every 4 tanks due to the DPF.
Two stroke in fuel is for quieter injectors though and won't have any effect on tappets which are cared for by the oil system.

Interesting, thanks! I'll adjust my ratio

I know, that the tappets are cared for by the oil system, but I can swear, the tappets are quieter with 2-stroke oil in the fuel. At least I'm 100% sure, I hear it that way

[cheshired5]

Originally Posted by paddy74

Interesting, thanks! I'll adjust my ratio

No problem. Only use low ash mineral 2 stroke.

Originally Posted by paddy74

I know, that the tappets are cared for by the oil system, but I can swear, the tappets are quieter with 2-stroke oil in the fuel.

Injectors can get a bit "clicky" and tappet sounding so it's probably the quietening of this that you're hearing.

The fuel and oil system don't meet, like the cooling system too so one system can't (or shouldn't) have an effect on the other unless you have a Euro 4 where fuel can cause oil dilution from failed regenerations.