i got a 2004 x-type with 90k miles on it. the previous owner had run it past oil change and it had generated a slight tapping/clicking noise. it doesn't sound like a rod knock to me.

i looked under the cam covers and a few of the buckets were a bit stuck, but the clearances etc seemed ok, and they seemed to loosen up a bit. there was a good bit of gunk under the cover closer to the front of the car.

i then thought i'd do an engine flush before i start looking for a new motor to put in. did that, put in new filters/plugs and oil. i'm not sure if it got better or worse but the sound definitely changed, and it isn't always there. i can hear it when it's idling, or when raise the rpm a bit (it sounds really bad at around 3000rpm). when i release the gas pedal the sound goes away for a while.

i have only worked on older cars before and was a bit overwhelmed by the amount of technology so any tips would be greatly appreciated! i'll try to answer any questions if i left something out!

here is a video of the sound:


at times the knock is more frequent, and then it can go completely away for a while.

thanks in advance if anyone has any insights!

 

also need to add it was low on oil when i got it. i put in some fresh castrol 5w30 before doing anything. it had a slight rattle (tensioner?) at start up that went away when i added the oil.

here's a second video taken immediately after the first one where to sound is much more frequent:

 

It's weird - at least from the second video - that sounds more external than internal ... once I had a an axle boot clamp let go and it made that sound when driving but ... you're not moving. Hmmm

If you take a long screwdriver and place it at various points on the engine and the non-rotating parts ... can you isolate where the sound seems to be originating from?

 

In the 2nd video, the clicking noise is ~175 clicks / minute. Assuming the engine idles at ~700 RPM, that's one click for every 4 rotations of the crankshaft, and every 2 rotations of the cam shafts. Seems too slow to be a connecting rod, piston slap or valve.

Agree with jimborino - it sounds external to the engine.

Dumb question: Have you listened for it around the serpentine belt, or the water pump belt?

 

One click for every 2 rotations of one of the cams...listen to your water pump!

 

thanks everyone! i was sure it was internal because it just sounds like the engine is dying. i'll go listen to the belts and everything they turn and see what i find.

are the belt tensioners supposed to be loose or tight? can i press them with my hand?

thanks a lot for the quick replies guys!

 

catman200: The water pump tensioner can easily be moved with your hand. Look for the small belt on the back / battery side of the engine. Remove the battery for easy access.

The serpentine belt tensioner on the front of the engine takes some leverage to move. It has a square hole into which you insert the drive of a 3/8" socket wrench to gain leverage. Space is tight, so a full-size 3/8" socket wrench won't fit unless modified it with a grinder. A cheap (<$10), simple solution is a 3/8" breaker bar - the head is small enough to fit where a socket wrench won't.

 

The first video it sounds like the clutch for the air conditioner pump cycling and if it got that much worse like the second video I would turn of the air and see if it goes away. I think it's to slow to be the water pump and it should be leaking if it's that bad.You can take the belt off(easy job) for a few minutes and see if the noise is still there. Cam bearings usually don't make a popping sound like that. If you rev it does the snapping increase? Idler pulleys usually make a grinding/howling sound and change pitch with RPM as with the water pump and alternator.One more video at different RPM's would help.

 

PS: I have also seen belts that are worn and climbing up the pulleys sound like snapping but should change with RPM also and sometimes you can see them jumping when it snaps.

 

I just remembered the power steering pump will make a snapping sound when the vanes get worn

 

I just remembered the power steering pump will make a snapping sound when the vanes get worn

 

well i took the water pump belt off, didn't change anything. then i tried loosening up the serpentine belt to the point the charger light came on (is this enough?) and the sound didn't change much. should i be able to see the serpentine belt tensioner move some tenths of an inch while the engine is idling? is this normal?

the funny part is, after this i started listening around again, and the sound went away for like 15 minutes, and then came back after the next start.

anyway here is a video of me giving it some revs. this hurt as it sounds like it's going to fall apart any second

and thanks for all your help so far!

 

I would remove both belts just to eliminate any auxiliary equipment.
Also take a look at your timing chain
remove the valve covers and rotate the engine by hand (socket )
I am suspecting some debris on the chain due to the ticks per min

 

i did that already. the cam covers were off and i turned the engine by hand and checked all the clearances. there were a few marks on the teeth but nothing that should make a sound. the chain was like new! it hasn't been run without oil for that long.

i'll take off both of the belts tomorrow and try to run the engine again. it was running completely fine for 15mins today with no sounds whatsoever, so i'm kind of hopeful again. it was running beautifully i'm just wondering what could have changed to make it sound like that again.

 

well the sound was probably internal. it went away and i went for a drive, heard a loud bang and it seized.

i'm going to fit a new engine in. thanks for the help anyways! wish me luck

ps. is the JTIS procedure for engine removal the way to go? or have you guys found out a better way? just want to make sure i don't go about it the wrong way.

 

Sorry to hear that.

Here's an engine removal post with excellent pictures:

https://www.jaguarforums.com/forum/x...ead-faq-11225/