anyone else have this issue? every time i start my xf after sitting for at least 2 hours the lifters tap for a few seconds at start up. i've checked the oil repeatedly and its ok. is this normal? will this cause engine damage? should i get it checked out? any info would be helpful... thanks.

 

Benji,
Just noticed that in my XF starting last week. It usually is when oil is low (on other vehicles) will be checking it today again and I just may add a touch of oil (not much at all) to see if I can get rid of it. I'll post up any news.

 

Noisy valves in this engine is common especially at start-up. The oil pools in the sump and takes a few seconds to start flowing thru the system when the oil pump kicks in. It'll be fine providing you don't make it a habit of revving the engine alot right after start-up. Give it a good minute warm-up before heading off down the highway.

 

Benji, mine never did this until my car turned up a little over 15k on the odometer, and coincidently it had been almost 6k since my last oil change.
In the past I've always changed my oil around 3k, and it never made a sound before.
I changed my oil & filter, and I'm going back to the 3k oil change interval.
So I guess I'll see if this makes a difference.

 

i bought this xf at 16,000, it has always done this, even after a fresh oil change...every 7,000 miles here. i know how the oil sits in the oil pan and the lifters dry out from sitting. just wondering if this will eventually damage the lifters. when i start it i don't go anywhere til the engine revs down on its own, about 30 to 60 seconds. anyways, just curious...BTW love this board!! you all are great!!...benji

 

I could be mistaken, but I thought our engine had overhead cams and therefore has no hydraulic valve lifters...only rocker arms/lash adjusters???

 

You can have hydraulic 'lifters' with any cam configuration, the are just a device for automatically taking up the slack in the valve drive train. This can be on a direct acting cam or on the end of a pushrod or rocker. As for the Crossfire - from the manual:

"Lightweight hydraulic adjusters in the rocker arms at the valves take up valve clearance for quiet operation. For minimum weight and maximum rigidity the compact rocker arms are pressure-cast aluminum. They pivot through roller bearings on rocker shafts bolted to the heads. Using computer-aided measurement and calculation techniques, valve dynamics are equivalent to that achieved by direct valve actuation through in-line tappets, but with far less friction."

 

Ingenious...I was envisioning the type of lifters in the old V-8’s that lost oil pressure and clattered away until they pumped up. Thanks for the info.

 

Well they are pretty much the same and do have to pump up after they have been standing and the oil has drained down.

 

can lifter arms be adjusted

 

If you read the thread you should have got the idea that the hydraulic lifters are the adjustment.

You would have to be really low on oil for this to become a problem.

 

oil level is ok problem still exists

 

I've noticed my XF making this tapping sound since I bought it (40k+ miles ago). I check my oil every time I fill up with gas and it's never been low on oil but I'm wondering if the tapping has something to do with the very low visc oil that is recommended? I haven't tried anything other than Mobil 1 0W40 but several people have mentioned to me that switching to a slightly heavier oil might help reduce the noise?

Anyone else have any thoughts on this or tried anything that worked to reduce the tapping sound? It doesn't bother me, I'm just curious.

 

let me just sum it up here.... it is normal... turn the radio on, it will be the first thing you hear...that is what my wife would do...lol...

 

My lifters were tapping when i traded my first Xfire in, turns out they had to replace half the engine, not exactly sure what went wrong, or if the dealer was telling the truth, but this was after my deal on the new car and trade was done and weeks later, so i believe him. I would take it in ASAP

 

Hydraulic Valve Lifters
A device that eliminates the need for mechanical clearance in the valve train of internal combustion engines. Clearance is normally required to prevent the valve's being held open and destroyed as the valve train undergoes thermal expansion. However, clearance requires frequent adjustment and is responsible for much operating noise. The hydraulic lifter is a telescoping compression strut in the linkage between cam and valve, consisting of a piston and cylinder (see illustration). When no opening load exists, a weak spring moves the piston, extending the strut and eliminating any clearance. This action sucks oil into the cylinder past a check valve. The trapped oil transmits the valve-opening forces with little deflection. A slight leakage of oil during lift shortens the strut, assuring valve closure. The leakage oil is replaced as the spring again extends the strut at no load. See also Valve train.

Positions of the hydraulic valve lifter, with engine valve (a) open and (b) closed. (After W. H. Crouse, Automotive Mechanics, 5th ed., McGraw-Hill, 1965)



Read more: http://www.answers.com/topic/hydraulic-valve-lifter#ixzz1cYOOD6zF

 

Don't know if this applies, but I had same issue on my '89 Probe, it too is 3 valves per cyl with SOHC :
Problem there was the tiny little holes in the rocker arms that supply oil to the hydraulic lifters can easily get clogged up, resulting in valve clatter, however this clatter does not go away.
Solution : remove the lifter train and rod out each lifter passage with a thin wire ( I used piano wire of the correct size ).
Worked fine on the Probe, no more lifter clatter .........
BTW, it had 106,000 miles on it .

 

Hey Benj,
If your lifters have gotten a little gunky, try adding some Seafoam to your crankcase. May do the trick and can't hurt the motor.

Info: Sea Foam | Tech Info - Gas Engines

 

There have been many, many threads about this noise and this engine (and its larger cousins) in the past.

The general conclusion on this forum and on mb-world has been that the noise is normal for this engine family - there's a good bit of valve noise when the car first starts, and then a little injector + valvetrain noise when the car is running hard - it's always "clicking" a little in some way or another.

For what it's worth my '04 Coupe with just over 60k has made a little valvetrain noise at startup since I bought it at 50k, through 2 oil changes worth of the recommended 0W40 now - one when I bought it and one at 56k - so changing the oil almost certainly won't get rid of the noise. It's probably harmless, though. Again, most people with this car and its Mercedes friends hear ticking noise to some degree.