Hi all,

I have a 2011 XFR that I've had a few weeks now, no lights, starts and drives awesome, but knowing of the tensioner issues I'm anxious about any sounds in the engine. Since it's new to me I'm not 100% sure what sounds "normal".

After the engine is warmed up, on idle, I hear a bit of intermittent knocking, definitely not the noisey injectors, kinda sounds like a bit in the crank case rattling around.

I tried to record it, but it's hard to hear it through the injector noise on the 5L.

Thoughts?

 

It sounds a bit like the well known torsion isolater / SC coupler rattle but hard to tell.
Your sound is a bit deeper in tone and more regular than the normal coupler rattle.
Easiest way to tell if you have a worn coupler is do you get a loud "clonk" when you shut the engine down - not every time, around every second time?
If yes you have a worn coupler (but you could also have other problem/s), if no then you probably don't have a worn coupler.
Another way to check is to take off the SC drive belt which takes the SC out of the equation then see how it sounds at idle.

 

Thanks oz. So far I haven't heard the clunk yet when shutting down the engine. I might have to take off the sc belt to check.

I saw in other SC coupler threads your f-type had a similar issue. What was the end result of your noise?

 

My engine is still as rattly as ever if not even more rattly, but the "clonk" on shutdown disappeared completely when the SC snout (with coupler) was replaced under warranty. I have a few suspects as to why my engine is so rattly - fuel pump bearings, SC tensioner, timing chains etc - but my money is now on the timing chains.
But despite being extremely rattly I have had no problems and it still goes like stink.

 

That's shitty that is still rattly, but awesome that is still running like stink.

Just so I have a record of the sounds of my car, I've recorded the left & right banks and engine shut off

Sound from left & right banks:

Shut-off:

I have a warranty with it, but the warranty isn't with any jag specialists only European motor specialists. I am hopeful that if I take it there they can diagnose the engine.

 

That sounds more and more like worn bearing noise to me - a deep rhythmic rumble.
If it is, best case scenario is it's the secondary high pressure fuel pump bearing (not that uncommon) = medium $ to fix/replace.
Medium case scenario is it's one or both of the two SC bearings, again medium $ to fix and you might as well get the coupler and SC oil replaced at the same time.
Powerhouse Tuning in the UK make a kit for this, here's their V6 kit: https://www.ebay.com.au/itm/Jaguar-F...YAAOSw-FpbPPQh
Worst case scenario it's one or more big end bearings, a few reported instances on this engine and almost always caused by running too low on oil = big big $ to fix/replace, more than the car is worth.

 

Former factory jag tech here. That is definitely timing chain noise. Not saying that the isolator in the blower isn’t bad, but that’s definitely chains. Have done a couple hundred of these chain jobs. If it has the original tensioners and levers, then it definitely needs to be done. Terrible timing chain design. But have had several customers get over 200,000 miles before needing chains. If you don’t follow JLR’s service intervals and keep the oil changed every 5,000 miles.

 

Jagman, may sound like a strange question but which bit of the noise in the videos is the chains in your experience?
Is the only way to tell from listening for a particular noise?
PS...Mine is noisier when the engine is hot, does that sound right? I always thought chains would be more noisy when cold?
Thanks,
Tom

 

I can hear them in all the videos. However, I do need to be clear since I am listening to a recording, the s/c is very likely making noise as well. I’ve replaced the nose cones on those a lot. It can happen hot or cold. Just depends on the vehicle. A good way to tell, which is what I do when I’m actually looking at one, is to use a dowel rod, stethoscope, long pry bar, or screw driver to listen to the specific parts. Another thing that I do is to take the oil filler cap off and and inspect the bank 2 chain for slack. Use a fairly long 90 deg pick or hook to pull up on the chain in between the 2 gears. Best to try this when The car has set over night and not been started. But not a bad idea to check when hot too. If the chain moves less than about 1/2 inch, that’s when I start listening real close. But I’ve seen several that make noise on the customer and then start acting right when they bring it to me. And then go right back sounding like the engines falling apart as soon as they pick it up. I’ll post some pictures when I get to the shop of the listening points.

 

Thanks all, I tested the chain through the oil cap and I get maybe 1/4 in flex in the morning before start up.

I'm going to take it into the warranty shop so they can do the diagnosis, both SC and tensioners are covered by warranty, but I would probably cover all of the extra bits that should be replaced while they are in there - tube under sc, plastic coolant pipes etc