L322 V8 tap tap tap

Got a strange tap which made itself known when I put 15/40 semi synthetic castrol Gtx in my 2003 4.4 Rangey.
I only really noticed it after a week or so and a week later have now done an oil and filter change using 5w/30 fully synthetic but the tapping remains. Changing the oil has cured the start up rattle it's had since I bought it in March last year but hasn't shifted this annoying tap.
It occurs between 800 and 1500 rpm using light throttle and disappears when the revs get higher using light throttle. The tapping also seems to vanish when it's accelerating or under any load but is also there on over run as the revs drop while slowing down.
I've done a little video to help.
Any ideas?

Can't see the video but sounds like typical vanos rattle.
Mine does have the occasional start up rattle and when it's cold it's quiet on idle but if I leave it on idle it will start to tap as it gets up to temperature
Have a look at beisan systems site
Is yours quiet when cold on idle ?

What's the problem with the video?

I can't see it on my phone for some reason

Does this help?

Nope, I'm sure it's my phone, I can see a great big advert for Bt broadband though

They're crap lol. Can you view it in YouTube by clicking the video title or the place holder where the video should be?

It's the only video in my channel here
https://www.youtube.com/channel/UCJ3VujsRGKqPUe2-xFMg_ZQ

I'm on hotel wifi so all I'm getting is 'loading' I'll try later when I'm home, you will have probably fixed it by then.
I have read various threads in the past including a couple saying about priming the hydraulic lifters by holding the rpm at something like 3000 for 2 minutes but sounds like a good way to kill it if the engine has underlying issues.
There can be more serious issues like timing chain guides failing which can be fatal if not corrected
My latest engine noise scare was the water pump luckily

I'm never that lucky. It does sound like a tappet but a heavier knock than a usual light tappet noise and can't figure out why it appears between certain revs at light throttle. Typical Range Rover!

All I see is a blank screen too....can hear it though!

Sounds like VANOS rattle, but that usually only occurs at cold start up....

Could be the chains rattling, but it is more of a tap than a rattle/slapping noise.

Might be worth chaning the chain tensioner anyway as they sometimes don't like oil changes....old oil is thicker and masks wear in the tensioner piston seal....new oil is thinner and the piston seal starts to leak and reduces tension on the chain guides leading to chain rattling.

Similarly in the VANOS units, if the seals are worn the thinner oil leaks past and VANOS rattle can occur...also there are tensioners on the VANOS Camshaft chains....these will also loose pump if the seals are worn and tension reduces

Thanks. The black screen is because I had my phone under the car and it was dark but capturing the sound was the point to the video anyway.
Chain tensioner isn't very old, probably about 6 months and only done around 10,000 miles although I was thinking the noise could be the chain slapping the guides.
As for the vanos, is it on the drivers side bank as this is where the noise appears to be coming from but I would say possibly not at the front or the top of the engine.
I will have it checked as I need to change the rocker gaskets to try and cure an oil leak I've got so it can be checked while the top is off.
Thanks lads.

i have similar on mine, but not so pronounced. to trace the fault use a long screwdriver and put it against the rocker cover, the stick your ear on the end of the screwdriver, obviously be careful of the moving parts at the front of the engine. i traced mine to around halfway down the passenger side bank, so my guess is it's a hydraulic lifter. when i had my rocker gaskets replaced the garage doing the job said the top of the heads were caked in baked on sludge, which they scrapped off as much as they could so it is possible there could be some in the oil way for that lifter. it hasn't got any worse or any better. you say you used 5w30 oil, recommended oil for these engines from BMW is now 5w40 as they are getting older etc, which i use in mine. if you do find sludge just decrease your oil change interval to 5000 miles until the oils detergents clean any sludge remaining.

Thanks for that. I am hoping it's a lifter after putting the crap oil in. Haven't done the air bleed exercise for the lifters yet but going to satisfy myself it's not something more serious first.
The car has quite a bad oil leak so it has about a litre a week, probably a bit less to around 300 miles (sounds bad doesn't it but can't see where it's leaking from so doing the rocker gaskets with crossed fingers) so my oil is always quite new and not sludgy, plus, LPG can help with keeping it all clean.
So, having had a noisy lifter, would you say mine doesn't sound like a lifter?
Thanks.

Hamster97 said:

Thanks. The black screen is because I had my phone under the car and it was dark but capturing the sound was the point to the video anyway.
Chain tensioner isn't very old, probably about 6 months and only done around 10,000 miles although I was thinking the noise could be the chain slapping the guides.
As for the vanos, is it on the drivers side bank as this is where the noise appears to be coming from but I would say possibly not at the front or the top of the engine.
I will have it checked as I need to change the rocker gaskets to try and cure an oil leak I've got so it can be checked while the top is off.
Thanks lads.

Click to expand...

VANOS is on both banks at the very front of the cam/rocker covers.....

Could be a hydraulic follower not pumping up....

Hmm, finally had a listen, it doesn't sound like mine, mine is quiet when cold and then starts to tick on idle once it gets hot and goes as soon as i give it any revs, yours is a more prominent tap which to me does sound like a lifter but as saint says it could quite easily be vanos.
If you are going to change the cam cover gaskets , you could change the vanos solenoid seals, LUD000010, but mine still leaks a bit from the front cam chain covers.
i did a flush on mine using 2 bottles of forte advanced flush although some would say not to as it can dislodge crap and also cause more leaks.
i have an electronic stethoscope which is great for finding rattles as you can touch the pointer onto individual parts and listen through the headphones much the same as the screw driver method already mentioned.
It doesn't really sound like cam chain slap to me either but you need to rule this out before giving it beans but the only way really is to drop the sump and look for plastic bits of guide.
mine tends to be quiet on start up from cold and only rattle for a second on start up when its warm but been left standing for a while as if the thinner warm oil leaks out through the vanos seals.

As HC says above.....

Also to note: changing the lifters requires removing the cams and retiming the VANOS and setting the cams......the official tools for this are EXPENSIVE as I found out!

Hi Ant,
Cheapest I have found but not sure how good or if they are the correct ones, i will be stripping out my vanos one day and doing the front end overhaul, i can feel it in my water (the water in my boot that is)
http://www.ebay.co.uk/itm/131589044509

holidaychicken said:

Hi Ant,
Cheapest I have found but not sure how good or if they are the correct ones, i will be stripping out my vanos one day and doing the front end overhaul, i can feel it in my water (the water in my boot that is)
http://www.ebay.co.uk/itm/131589044509

Click to expand...

Bloody hell Andy, thats a good price.....can be over £400, I paid £250 for my set about a year or so ago!

Sounds like I'd best hope it's vanos seals lol