After much reading here I just can't seem to find the answer to my question(s).
My 2003 XJR ( 41,730 miles) recently developed the dreaded tappet "clicking ( or could it be injector clicking sound?) when the car is first started in the morning even with morning temps still in the 60s here in Boston. Subsequent starts during the rest of the day seem to be just fine

Background:

1,oil ( 0W40 Mobil 1 European blend)) with around 900 miles on it. no additives ever used.
2.temp at start >60 degrees
3,fairly loud "ticking" sound from passenger side bank until engine warms up
4.Sound seems to be coming from underneath blower ( where the 4 injectors are)
5. As engine begins to warm the ticking sound slowly diminishes then pretty much goes away after 5 minutes or so with what would call "normal" subdued injector solenoid "noise(s)" ..not loud at all
6. Car is indoors in cold storage Nov1 to April1 with oil and filter change at storage time.
7 car driven only 1200 to 1500 miles per year.
8 Since its SC...no hydraulic lifters or VT mechanism to screw up...eliminates them

Obviously I am praying that it is an injector solenoid noise that diminishes as the injector body "heats up" and NOT a worn shim in the lifter...arrrrghhh !!! FAAAALUSH $$$$$ The trick here is how to definitely tell which is the culprit.

I'm hoping that a member here has seen this scenario ( Jaguar mechanic?) and can shine some light on this problem which I'm sure is probably pretty common in various engines in the big cats. Anyone here ever use a "mechanics' stethoscope" to pinpoint the noise ? I tried with a screw driver but you can't "get at" the injectors under the blower itself.

Thoughts , comments and questions

Those of whom I have talked to "lean " towards it being a lifter. ( please say it isn't so !)They base this on the ticking noise diminishing as the oil temp and pressure rises. To "fix" this would require massive disassembly and big time Jaguar"savoire faire" and big bucks ....Shade tree mechanics (me) need not apply....
So a question becomes .... has anyone seen a ticking noisy injector solenoid quiet down as it gets hotter ? and "sounds like a lifter then quiets down ? ( I hope)

Next question... the "correct" oil is 5W 30 although as far as I've seen 0W 40 syn is supposedly acceptable too , in fact it meets a couple of more "specs than the 5W 30 oil... so might going back to a slightly higher low temp end viscosity of 5W vs 0W help ?

No additives have ever been used in the engine...... would using something like Risone quiet down a start up noisy lifter? I'd hate to do this...but.

From what I've learned , the ticking noise from a lifter is the result of a shim getting just a tiny bit smaller making the metal on metal ticking sound until things "expand" and get tighter after warm up. Also, I hear that the Europen blend oil is actually made for engines with much tighter tolerances compared to the AJ27S in my beastie...so maybe a little thicker viscosity at the low end (5W) might help ? Might going back to 5W 30 solve this if it is indeed a noisy lifter ?
Most important question... If I do NOTHING and "get over " some ticking noise for 5 or so minutes at start up ( start ups for the rest of the day are fine by the way) will I be doing even more damage or is a what I've got now pretty much the extent of this ?

Any and all replies/comments SOLUTIONS?? !! really appreciated..Thanks guys !

Did a little more reading in the manual.... Gee it almost looks like on an SC setup, changing out injectors might be an even bigger job than checking valve shims? SC cooler has to be removed to replace any injectors... lots of work...now I don't know which to "cheer for" ? Valve work or injector? Maybe I'll get really lucky and the change back to 5W 30 oil does the trick...fingers crossed

 

Switch back to 5W-30 like you suggested and see where that puts you. Drive it a few days and when you start it up cold one morning about 3 days after the oil change, determine if the noise is the same, better or worse and report back here.

 

The engines do not have lifters, so that can be eliminated.

99% chance Thad it's normal injector noise.

 

I'll do it tomorrow.... and let you know. Boy it would be GREAT if thats all it was ...Thanks!

 

Mickey, if you could hear this noise I know you'd say its not normal injector noise... I'm hoping that the change back to 5W 30 solves this as Addicted to Boost suggests.
Thanks for your comment..

 

It's not the oil. The noise would not go away as the engine warms.

My engine makes a very similar noise when cold.

 

Take a long solid rod, and while the engine is running, stick one end in your ear, and the other on suspect spots in the engine. Or get some harbor freight stethoscopes, I bought them on a whim, without any need for them, and they have been invaluable since for noise diagnostics.

FWIW mine seems to make a kind of similar noise, and I've traced it to injectors. They're still relatively loud at warm idle, but that seems to be the norm for these cars.

 

Oil - put what Jaguar recommend in - 5W30 is the lube to use.

 

From the owners manual:

SAE viscosity rating

For climates ranging from –30°C (–22°F) and +50°C (+122°F), the following oil viscosities may be used:

0W–30
5W–30 (preferred)
0W–40
5W–40

 

I'm headed to harbor Freight this AM to pick up a stethoscope . Since the clicking ( tappet like sound) goes away as the engine warms, the key question is 'Does ( can ) an Injector solenoid make such a noise and THEN diminish and pretty much go away when the block and injector body gets hot ?

From what I noticed listening with a screwdriver is that all injectors make a clicking sound with some more so than others. So has anyone seen an cold injector make a quite loud noise on start up then slowly go away as the engine gets hot ?

 

My 2001 always had noisy injectors on the left side. Might try SeaFoam or BG44K to clean up injectors.

Be careful with the stethoscope around reciprocating parts.

 

Please NO, not Seafoam! The 1950s are long gone.

It has nothing in it that will help anything but 2 stroke carburetors and the fact that it's 50% light petroleum oil makes it the last thing you want near a potentially carboned injector.

 

has anyone come to a conclusion on this thread (between oil additives for valve clearance on the shims or injector tick where obviously oil additive wont do antything

 

I don't think this is injector noise, mine does the same from the same location, i rotated injectors but noise stays in passenger side bank front (not uk passenger of course)
Pulling the cam cover and checking clearances on the loud side would help isolate the noise, same for running engine without belt for a while

 

Maybe an exhaust leak at the cylinder head??

 

yeah, it makes a sense, not that loud but certainly sounds the same