Whats this sound! after you allow days of rest

[VFSV6FORME]

I have struck this before on most of the early Quad cams V6's and other like my old VR commodore that has the Buick 3.8L in it so her goes.

Now we will talk about the VE V6 with the LEO engine in it and I would like to know why when you don't start the car for 4 to 7 days plus and when you start it you hear a RATTLE coming (Sound like a chain as these Engine have No bleed down lifters like older cars like the VR commodore Buick Engine days) hear a RATTLE coming from the Engine for 1 to 1.5 seconds AS SOON AS THE CAR FIRES UP PRONTO and after this it gone and not doubt when the Oil pressure is up so what is it as again these quad cam engines not have hydraulic lift that they are prone to bleed down so what causes this sound. Now if you start this LEO Engine every day or even two days and I think some three day period it does not have the noise.

By the way Our VF V6 (SIDI) which has 3200 K's on the clock you can leave it for two weeks then start it and you hear nothing.

 

[VFSV6FORME]

Reading,Reading and more Reading,,,seems that theses Quad Cam 3.6L Engines have Hydraulic lifters....... Another Site quotes "The Hydraulic lifters are known for getting very noisy and creating noises that can lead people to misdiagnose the above mentioned timing chain fault as the cause. Noisy lifters are a common issue with the VE Commodore".

Interesting!!! , you learn things every day

 

[DavesSV6Tonner]

Very interesting indeed. I had no idea the Alloytec V6's valve rocker arms have hydraulic lash adjusters.
Learn something new every day.

 

[VFSV6FORME]

My issue is possible not a issue but could be a rocker arms hydraulic lash adjusters as you hear it 000000.1 seconds after the Engine starts and its gone under 2 seconds later.
The same with the old Vr Comm as yo hear it immediately after the Buick engine starts and it goes after two second or 3 seconds. The funny thing is with the VR the car that I have driven for 24 years when it does this its OIL CHANGE TIME.

 

[UTE042_NZ]

The youngest VE is 6 years old now, and the oldest is 13. They all have a fair few miles on the clock today. The LE0 variant (variable cam phasing) was only used on the 3.6 litre LY7 wasn't it? So if exactly the same the rattle was present in other engines it would probably not be related to the LE0 differences but to similarities between the engines (such as the four cam) design.

As you say rattle is often a symptom of wear and may be quietened by oil. If it takes a prolonged period of inactivity to initiate, the rattle is quite possibly due to the time it takes for the oil to drain completely from the worn component(s). I would expect head components to show a noise in much less than 3 days. Could be slightly worn gudgeons and/or big ends with/without a little piston slap, or it might be exactly what your memory tries to tell you it is - and it takes 3 days for the timing chain to completely drain and dry out.

The ambient temperature should affect the inactivity time too.

 

[Fu Manchu]

Cam Phasing was on both motors. On LE0 Cam solenoids operated the inlet cam timing.
On LY7 it had 4 cam actuators/solenoids/phasers. The operated the inlet and exhaust valve timing.

 

[Fu Manchu]

It could be something as simple as exhaust rattle.

 

[VFSV6FORME]

It could be something as simple as exhaust rattle.

Its to precise. Start it everyday or every second day it make no noise. Dont start the car for 4 days or more it make the noise immediately at starting 00000.1 of a second after the engine starts and it goes totally off (full quiet) after 1.5 Seconds after the engine has fire up. For me it has something to do with Oil Pressure. I spend yesterday reading about this and it seems to happen quite often.

I have seen some Video on youtube where a VE V6 Engine starts, then the Noise start after 2 to 5 seconds after starting (My one is IMMEDIATELY) and rattles on but after 2 to 6 seconds of running it stops. Now my one is not like this.

Again Me thinks it has something to do with oil Pressure either to do with chain tensioner, or rocker arms hydraulic lash adjusters. Who knows maybe after 3 days the oil bleeds out of the Chain Tensioner or the rocker arms hydraulic lash and when you start the car Oil Press come up and presto the rattle is gone.

I also read a story on a Ve Sv6 where a guy has a Issue with the same, very similar like mine (leave the car still for a few days then start it and it immediately rattles then stops and this car had around 80,000K on the clock) then he took it to a Holden dealer and supposedly had the 3 chains replaced, dont know if it was a warranty job or not but when the car came back the car was the same so he took it back and they replace the oil switch ( what!!! that wont not cause this issue) and after this he did not reply on the post.

 

[greenacc]

It's the timing chain noise until the tensioners build oil pressure. It's normal for a few seconds.

 

[VFSV6FORME]

It's the timing chain noise until the tensioners build oil pressure. It's normal for a few seconds.

That's what I'm thinking about. If this is the cases the Tensioners must bleed out after resting for a few days