I have a 2003 XK8 coupe with rattle on start up. about 120K miles, very well maintained with regular oil changes.
The noise occurs when the car has been sitting overnight.
It sounds like rod bearing noise that is quieting as soon as oil pressure comes up.

The noise seemed to start after I was off warranty and started doing oil changes myself or at a non-dealer garage.
The noise seems to be reduced with synthetic oil and with lighter weight oil (5W-30W), increasing noise occurring with heavier weight oil (10W-30W) as well as increasing noise with STP additive.
This would seem to indicate a problem with oil draining out of crankcase and taking longer to reach critical bearings on start up with thicker oil.
Noise seems to be reduced if car is on level ground, however, this is very subjective.
The noise was investigated at local mechanic who felt it originated within the block as opposed to timing chain area, however, a loose timing chain would also make a similar type of noise.
I noticed the non-dealer mechanic used a MANN brand filter and i believe I used a Fram or Purolator filter.
Questions of the hour:
1) Does the OEM filter for the 2003 and later 4.2L have an internal check valve?
2) If not, is there an internal check valve that prevents crank case drain that we should check for correct operation or replace for good measure?
3) Is there a check valve that maintains timing chain tensioner position?
4) Any "Helpful Hints from Heloise"?

Kind Regards,
Steven

 

I also have this issue- looking forward to responses (and NO I haven't checked the oil filter yet

 

I do have brother that used to be a parts and service manager for a Ford dealer during these same years. At that time, Ford products did use a check valve in the filter.
Wondering if the Ford influence went to this part of the product.

Regards,
Steven

 

What oil filter are you guys using? Most filters have a check valve to keep oil in the passages and not leak back around the gears in the oil pump when it's been shut down for a long time. Many years ago Fram got busted for using cheap cardboard check valves and the engines would rattle until pressure built up. A simple swap to a different make oil filter fixed it.

 

I agree, I used a Fram or Purolator, the non-dealer garage used a MANN brand product.

Also I did check the FAQ section - in terms of elimination of other causes, I replaced "things that spin" tensioners, water pump, idler pulleys, serpentine belt, etc. as a preventative maintenance move at around 100K miles (wheel bearings are a pain in the butt).
It may be time for an OEM filter.
Curious if our mechanic forum participants knew with certainty. I have new synthetic oil in there now (3 rounds of oil change in last 10K miles to try to resolve). Something just doesn't sit right about putting oil back in after draining (like wearing socks the next day?).
I have never heard of "MANN" brand filters but the mechanic I use has been extremely responsible. I think it might be incomplete cross reference spec. Filter fits but maybe has no check valve as use was intended for vehicle with internal check valve.

 

Lots of threads on the forum about this.
It's probably not your oil filter but an oil pressure loss of the Variable Valve Timing valve. Pre 2003 cars could have some serious timing chain tensioner issues but that was upgraded in the 2003 - onwards.

I have the same noise (I think because I haven't heard yours) and it goes away after a couple of seconds. Sounds like a loud rattle and if you get someone else to start the car while you listen, you'll notice it is coming from the top of the engine and not the bottom. Has nothing to do with your oil filter.

 

Hi Bernie,

I have done the thing with someone else starting car and listening/feeling as well as had car in mechanic's shop for a week with them starting each day with the same attempt to find source (one guy starting car, two under hood "laying on hands"). It did seem to all as though origin was towards middle of engine, front to back, there are varying opinions as to top to bottom (personally - I favor about 1/3 way down from top).
This is a 2003 so the new style timing tensioners are the "new and improved" style. I follow that these are new and improved, etc., however, this is not a healthy noise.

Just curious, are you running an OEM filter?

1) I am very open to suggestions and greatly appreciate them.

2) I found lots of threads, including yours, I tried to respect "rules of the road" and not "hijack" the threads. Only a few seemed to end up with a resolved condition. These seemed to be filter related. Perhaps a "sticky" might help. My apologies if this has been added to one of the general info topics.

3) I have had several VVT cars, all seem to have a few issues as they age so very open to this possibility. If this is a VVT issue, does anyone know if there is a maintenance procedure? (gee whiz you have to replace "x" to prevent/cure oil pressure loss in the VVT). Hopefully "x" is not the entire engine.

3) With the "new and improved" tensioner, is there an oil chamber that could leak down and reduce tension until oil pressure comes up? Trying to distinguish between "new and improved" and "new and perfect".

4) Is there anyone out there that:

A) Experienced the "rattle", ignored it and had catastrophic failure 10K, 20K, 40K miles later?
B) Experienced the rattle and had no problems after 10K, 20K, 40K miles?
C) Found a problem with new tensioners?
D) Knows a check/procedure for VVT?
D) Cured the rattle with oil filter/oil type?
E) Know the correct direction for "circle chant"?
E) Cured the problem in another way?

Current plan of attack (any suggestions?) by process of elimination:
1) Chant in a circle to right.
2) Test to see if problem is resolved.
3) OEM Oil filter.
4) Chant in circle to left.
4) Test to see if problem resolved.
3) Pop the valve covers when cold and try to check tensioners status from the top. Posts indicate this is possible with pre 2003 but not clear for post 2003 cars like mine.
4) Check the VVT (anyone know how), replace any known seals, bearings, etc., at the same time.
5) Chant in a circle both ways.
6) test to see if problem resolved.

What i don't know is if there is a point where i need to take off timing chain cover to rule out lower chain issues and if I need to prepare to take on that task instead of just valve covers or try the above and go back in again if needed.

I know this wont be definitive as there is a possibility in each step that the chanting is really the cure. But you don't buy a Jag unless you want a little mystery in the mechanics.

Lot of thanks and respect to you and ALL on the Forum,
-Steven

 

The new style chain tensioners are locked in position by a ratchet action that is set from the first use. There have been a couple of reports of the ratchet failing. It would probably worth while to take the cam cover off after sitting overnight and see if the the tensioner has collapsed.

Mann filters have a check valve, I have been using them for many years.

 

Yeah, mine began with that little rattle at start-up. A month or so of occasional driving and something went 'graunch' at start-up. Too much experience with noises in engines at start-up told me timing chain and/or other components.

Here's my thoughts, fwiw. I have yet to replace a cam phaser on any manufacturer's engine. Maybe one or two control solenoids but they just caused an emissions code to set - no complaints of noise. The sudden torque applied to an 'at rest' engine during starting typically finishes off weak timing components - chains, tensioners and guides. Think of it as the difference between someone giving you a shove vs. sneaking up behind you and bitch-slapping the beejaheesus out of you. When I started getting paid to work on cars in '70 I did a LOT of Pontiac timing chains. 100% of the time the customer's story went, "It was running fine last night but it wouldn't start this morning." That sudden torque of the starter ripped the teeth right off of the cam gear - every single time.

And what did I find on mine? One of the chain guides chucked its nylon covering and the chain grabbed the edge of the metal backing. Yup, the PO had replaced "just the tensioners", which I have warned others about, and the rest is history. Do the job right and replace all of it or suffer the inevitable consequences later.

 

RJ;

Thank you for insight on both fronts. Particularly on ruling out oil filter.
Really appreciate not dumping $85 worth of oil/filter, etc., I will proceed to second "chanting in circle" then look under valve covers.

 

The definitive answer to your problem based on two XK8's with the same issue. Firstly, you can ignore it forever as it is not progressive nor a sign of other issues. The VVT's have an internal sealing that wears with age and they leak down after a long shutdown, especially after the oil had a chance to get hot and thin to its operating spec. When you startup the last place to see oil flow is the top end and these little devices for obvious reasons. Regardless of the climate, cold oil is a little thicker and moves more slowly than warmed oil. When you increased the "winter" rating number of your oil, you compromised the cold start flow regardless of ambient temperature. Consequently, it takes a little longer for the pressure to firm up the VVT mechanism. 5W-30 is recommended for our climate, perhaps in amazingly hot areas or track running you might want something that goes up to 40, be careful here.

I use 0W-30 and on the coldest of days I only get the clatter for about ten seconds or so and not very loud. My friend with his XK8 and Royal Purple 5W-30 hears it for longer and the engine clanks as they normally do longer when it is very cold. Royal Purple is on the thicker side by its nature.

Yes, your filter cold be draining back and merely contributes to time to top of engine flow. Try the better quality of the Motorcraft filter as it is factory spec. I am a little sour on Fram as they are not what they used to be. Hastings filter across their quality range are well made and very cost effective.

Remember that flow is more important than thickness of the oil for moving parts separation. As long as oil can maintain specified characteristics at the operating temperature range, you are fine. This is why 20 weight is now a standard since the products now exist that can maintain characteristics at expected operating temperatures and allow engineers to do what they always wanted. 30 was a trade-off due to lubricant limitations which are not there anymore. This is why you see a lot of backward compatibility. Of course our cars cannot go there for their own reasons, such as tolerance at design and now age.

Most of your damage is done at cold start. This is why I use 0w-30 to maximize pump up and flow as early as possible on a vehicle that might have a lot of short trips or infrequent use outside of my usual long distance runs.

You can fix your VVT's for no reason or try 0w and see what happens. Also install the Real Gauge oil pressure kit and check that your pressure is at spec throughout the RPM range at operating temperature, at least one hour of driving.

 

Beav,

I agree on the "bitch slap" issue. I have done the cleanup on more than one engine where camshaft quit turning and crank kept going.
I will look at condition of timing mechanisms as i go through process.

Whitehat,

By George, I think you may have something here!
Something=valuable experience.
1) I had just heard of the "0W-30W" oil a few days ago. Makes sense.
2) I will go back to OEM on oil filter or to Motorcraft if they have a tighter spec.
3) As far as the VVT issue, is the seal you speak of part of the VVT solenoid valve? these seem to be available from Jagbits (part # AJ810570) for $230 each. Very OK with that.
Without obligation to diagnose without being present, etc., would replacement of this part resolve the leak down within the VVT you are speaking of?
4) Do you know if there is a check procedure to verify performance of the seals within the VVT solenoid (or other applicable part) beyond replace and see if it is cured? ("if this part wiggles, it is a VVT problem" or "when you apply voltage here when cold if it goes clunk, it is a VVT problem")....sounds like a Jeff Foxworthy routine.

Many Thanks to all!
Steven

 

Whitehat,

As a follow up i searched a lot of related VVT topics and came back to forum but in the XJ8 category.

I found this thread to be very interesting: https://www.jaguarforums.com/forum/x...sioners-71904/

(hope that link works)
It would seem that seal is probably within the VVT unit itself, not the solenoid actuating it. Replacing solenoid seems like a lot more fun.

Kind Regards,
Steven

 

It's the VVT unit (number 7) below:



Number 7

Nothing related to oil pick up, oil grade or weak oil pump.

 

#3, i cannot say whether this is the correct part number, but when my friend had his VVT's rebuilt, the "awful rattle" went away. It must be said that he had an early XK8 where the setup might be a little different. I am pleading ignorance here as you need someone with more experience in diagnosis (#4). My knowledge is second-hand with first hand observation of major improvement. The technician who performed the repair also said that it would not cause damage over time, just noise at cold start.

It would also be good to remember that people's perception of noise varies. These engines, even when perfect, have a sound when they are cold; this is normal. This is somewhat affected by oil viscosity and majorly be temperature. Funny too is that if you are located next to a sound reflective surface, the cacophony at cold start can be maddening. It amuses me after I invited my technician over one morning to hear the serenade. He said that it was normal, cold metals, differential rates of expansion, cold combustion chamber. And frustration to the girlfriend wishing that the car would blowup.

Have someone experienced listen to what you are hearing before you spend time and money. And I strongly advise that you convert using Real Gauge with the oil pressure option. An oil gauge is a diagnostic tool which can tell you a lot about bearing tolerances, etc. There is a thread with the pressures at various RPM's. Too high is also a problem and can contribute to noise and bearing damage.

 

the seal is definitely the problem. the solenoid is not going to cause this issue. called my tech who fixed my friend's VVT and he said that it is in the VVT itself. You will probably need a tool or make one to lock the cams when you perform this dismantle.

 

forgot to mention, do not use that STP stuff. it was useful in a different time and could be thickening your oil above its formulation spec. good oil is fine as is unless you need something very specific such as zinc additive for flat-tappet cams. this does not apply to us.

 

I've had this quick burst of noise at startup for years now and many tens of thousands of miles. It's never goes on for more than a few seconds and doesn't affect anything. Can be a bit embarrassing if people are nearby though.

Replacing the VVT units involves tearing apart the timing cover of the engine and all the crap on it. Not worth it unless the noise gets worse.

However, I installed 200 cell cats, an xpipe and sports mufflers which help to drown out the racket with a nice loud startup roar. That's the best remedy I think.

 

Confirmed, STP is not good on these engines, lasted through the next morning when start up issue was much worse, immediately changed back out. Yes very good on flat tappet cars (my 62 alfa spider likes the stuff).

Pursuing costs now to replace VVT units with independent mechanic they (VVT) are not cheap.
Looks like it does mean timing cover, etc. has to come off. A little bummed as I just replaced all the stuff that spins (tensioners water pump, t-stat, etc.) wished i had gon e in then.
I understand if it is the VVT the rattle may not worsen over time, but it is not the luxury experience I signed up for. Also, I am an audio consultant with background in noise and vibration control. Not the best advertising after the meeting in the parking garage.

Work won't happen for a week or so.
Will report back
Thanks,
Steven

 

since you are committed to fixing the problem and it will not be inexpensive, why not try something with a small possibility of success. do a complete oil and filter change using something like Amsoil (their top tier product, Signature series) or Mobile 1 (use their higher grade synthetic, apparently there are now two grades) 0w-30, no extra additives and take it on a few long highway drives, at least an hour of driving, highway speeds. See if this flushes the oil channels or frees any seals.

wondering if your problem was caused by extra additives gumming up the works.

of course in a concrete garage their will be sound echo. i just want you to remember that even when perfect, these engines have a sound at cold start for a short time that will echo in certain places.

BTW STP is garbage for anything, find an oil formulated for your older vehicle's flat tappets. this stuff really makes a mess of the engine internals.