Knocking Noise... Sv6 Top back right Piston area (Facing Car)

[Fu Manchu]

Is it a really flogged out purge valve?
Edit: no. Would do that at the start.

Also use the garden hose method to listen around the area.
You could fab up a fancy set up with garden hose, a t-piece, then run the hose into a cheap set of ear protectors. Drill a hole into each one to push the hose through and chuck away the foam.

You could also use them to listen to the sea and listen out for Messerschmitts.

 

[vr304]

I definitely hear it in the top of the engine and i think the head and not the block.

Off peoples points of views its looking like bad lifter or shitty push rod, just want to get some more points of views before I start dismantling my engine.

Those v6 engines are overhead cam so no pushrods and possibly no lifters either depending on the cam setup

 

[Skylarking]

Those v6 engines are overhead cam so no pushrods and possibly no lifters either depending on the cam setup

Correct that there are no pushrods as such but there are always hydraulic lash adjusters (which is what a lifter is) in all modern engines…

IIRC, the HFV6’s operate the valves via a roller rocker of sorts. The cam profile presses on a roller which sits in the middle of a rocker while one end of the rocker pivots on a hydraulic lash adjusters (relatively fixed point) and the other end pushes on the valve stem to open the valve as the cam pushes on the roller…

So you can still have parts fail just like a pushrod engine. You can have a blocked hydraulic lash adjuster which will cause noise similar to lifter tap, a failed follower (rocker) roller or complete follower failure or a broken valve spring… all cause ing noise…

What the likelihood of such failures are and whether they are prevalent on HFV6’s like LFX I don’t know.

 

[tha_sv6]

Correct that there are no pushrods as such but there are always hydraulic lash adjusters (which is what a lifter is) in all modern engines…

IIRC, the HFV6’s operate the valves via a roller rocker of sorts. The cam profile presses on a roller which sits in the middle of a rocker while one end of the rocker pivots on a hydraulic lash adjusters (relatively fixed point) and the other end pushes on the valve stem to open the valve as the cam pushes on the roller…

So you can still have parts fail just like a pushrod engine. You can have a blocked hydraulic lash adjuster which will cause noise similar to lifter tap, a failed follower (rocker) roller or complete follower failure or a broken valve spring… all cause ing noise…

What the likelihood of such failures are and whether they are prevalent on HFV6’s like LFX I don’t know.

its very helpful, as i want to limit it down the THE possible things, so when i take it back to my mechanic, ill get his 5 cents and if i can ill buy the parts myself... and fix it.

or let him take it and fix the problem at hand.
ill worry about a timing chain later... ffs

 

[mirrabucca]

Correct that there are no pushrods as such but there are always hydraulic lash adjusters (which is what a lifter is) in all modern engines…

IIRC, the HFV6’s operate the valves via a roller rocker of sorts. The cam profile presses on a roller which sits in the middle of a rocker while one end of the rocker pivots on a hydraulic lash adjusters (relatively fixed point) and the other end pushes on the valve stem to open the valve as the cam pushes on the roller…

So you can still have parts fail just like a pushrod engine. You can have a blocked hydraulic lash adjuster which will cause noise similar to lifter tap, a failed follower (rocker) roller or complete follower failure or a broken valve spring… all cause ing noise…

What the likelihood of such failures are and whether they are prevalent on HFV6’s like LFX I don’t know.

Sounds like the system used in the old Astron Mitsubishi OHC engines. My old Magna had a tick tick tick at idle, classic valve train noise. I traced the noise using a stethescope, to around the cylinder one area. Then I decided to take off the valve cover and start the car to see if I could hear where the noise was coming from. In the old days, with Holden grey motors, you could take off the valve cover and run the engine to adjust valve lash or listen for noises. The oil flow to the rockers in those engine was very slow, so no mess to speak of. Not so the Mitsubishi engine! My garage ceiling still has oil stains on it! Oil everywhere! But I did find cylinder one inlet lifter wasn't taking up the slack between the cam and the valve. Off to Repco, one new hydraulic lifter ($26). replaced and all good.
I mention that because, is it possible to adopt the same fault diagnosis techniques on the VF V6 engines?

 

[Skylarking]

I mention that because, is it possible to adopt the same fault diagnosis techniques on the VF V6 engines?

You can always adopt old school techniques to diagnose mechanical noise, especially if you don’t mind oil stained ceilings

Me, I’d leave the valve covers on and stick to a mechanics stethoscope to localise noise as best I can. Then if I suspect a lifter, follow any valve lash check/adjustment procedure that the manufacturer recommends