Engine experts- what would cause a top-end ticking besides injectors?

[Stainless 45]

I've noticed a metallic tick-tick-tick at idle which seems to vary with rpm. 500-900 it's there, 1000-1100 it's gone, 1200-1400 it's there again, etc. It sounds similar to the injectors, but not the same. I can hear it with the hood shut but with the hood open it gets lost in the injector and intake noise. This is not the crank/ bearing noise that some have experienced, as it's steady and a lot quieter. Sounds like the valvetrain noise American V8's made but since we (M3's) don't have pushrods or rocker arms I'm at a loss. It is similar to the metallic racket we get at startup as the cats are being heated but when that's over this faint ticking remains. Coming from the left side. Could a valve need adjustment? Anyone else notice this?

[elm3]

Originally Posted by Stainless 45

I've noticed a metallic tick-tick-tick at idle which seems to vary with rpm. 500-900 it's there, 1000-1100 it's gone, 1200-1400 it's there again, etc. It sounds similar to the injectors, but not the same. I can hear it with the hood shut but with the hood open it gets lost in the injector and intake noise. This is not the crank/ bearing noise that some have experienced, as it's steady and a lot quieter. Sounds like the valvetrain noise American V8's made but since we (M3's) don't have pushrods or rocker arms I'm at a loss. It is similar to the metallic racket we get at startup as the cats are being heated but when that's over this faint ticking remains. Coming from the left side. Could a valve need adjustment? Anyone else notice this?

Mine has the same, but it is the injectors. It is hard to isolate the noises under the hood. If it was a sticky valve, it would somewhat disapear after the engine is warmed up.

[Stainless 45]

Thanks, it actually seems a little more noticeable when the engine is warmed up. Doesn't sound like an injector to me- similar but not the same.

Anyone else? Surely some of you listen to your engine now and then...

[Mr. ///M3 RD]

Bad gas ... wear ... some mechanical issues. Do have the dealer check it out you are under warranty ?

Tip ... never fill your gas tank at a station where you see a truck just filling the gas stations tanks. It creates turbulence in the gas stations main tank(s) and some of the foreign tank particles may end up in your gas tank ... be on guard for that. Just saying.

[JerryK73]

How many miles on the car (around 60,000 miles)? It could be that your valves need to be adjusted. Your car might be due for inspection 2

[Mr. ///M3 RD]

Originally Posted by Stainless 45

Thanks, it actually seems a little more noticeable when the engine is warmed up.

As you know this is quite normal ... your engine components expand and clearances increase therefore noise is much more noticeable.

Make sure you are dealing with a good BMW dealership when this is being diagnosed. You paid good money for this car don't let them brush you up. Take your car there when the engine is real hot and let them listen to it right there and then.

I say this since I have experienced good and bad dealerships believe me they are out there.

[Mr. ///M3 RD]

Originally Posted by JerryK73

How many miles on the car (around 60,000 miles)? It could be that your valves need to be adjusted. Your car might be due for inspection 2

Also this ^^^ 100 %

[tony093]

i was under the impression that S65 didn't need valve adjustment.

[Ateam]

the e46 s54 needed valve adjustments but the hydralic lifters and valves need no adjustment for life of engine

[BMRLVR]

Originally Posted by Stainless 45

I've noticed a metallic tick-tick-tick at idle which seems to vary with rpm. 500-900 it's there, 1000-1100 it's gone, 1200-1400 it's there again, etc. It sounds similar to the injectors, but not the same. I can hear it with the hood shut but with the hood open it gets lost in the injector and intake noise. This is not the crank/ bearing noise that some have experienced, as it's steady and a lot quieter. Sounds like the valvetrain noise American V8's made but since we (M3's) don't have pushrods or rocker arms I'm at a loss. It is similar to the metallic racket we get at startup as the cats are being heated but when that's over this faint ticking remains. Coming from the left side. Could a valve need adjustment? Anyone else notice this?

The noise you hear is indeed the valvetrain. It is quite common in a high performance engine to have some mechanical noise in the valvetrain. Both my M3's made the exact same noise you are describing and you should not worry, it is completely normal.

The valvetrain noise from American V8 engines is not pushrods or rocker arms but is in most cases the Hydraulic Lifters (except of course on solid lifter engines where the noise is indeed the required clearance in the valvetrain).

Although we don't have pushrods or rocker arms we we do have hydraulic lifters (hydraulic lash adjusters in BMW terminology) so the S65 don't require and there is no adjustment on valve clearance.

I understand that a noise like this is kind of annoying and we all would like our engines to be completely mechanically silent. The fact of the matter is that most all engines have some mechanical noise, there are a lot of moving parts in there and it is nearly impossible to eliminate mechanical noises.

One thing to note is that the M3 uses an Aluminium hood with no sound absorbing material on the underside. I think that is another reason that mechanical engine noise is so easy to hear on the M3, even with the hood down. Although most people don't think much about those sound absorbing pads on the underside of their hoods, they are extremely effective at sound abatement, it is left off of the M3 for weight purposes and the fact that they want you to hear the engine.

[JCtx]

Originally Posted by Stainless 45

I've noticed a metallic tick-tick-tick at idle which seems to vary with rpm.

Perfectly normal, by your description. Some engines are a little noisier than others due to manufacturing tolerances. By the way, must pushrod engines are superquiet by comparison, but mostly due to their iron block. Just listen to a Vette, which has pushrods but aluminum block (like ours), and they make much more racket than our cars. As engine heats up, and oil thins out, the noise is more prevalent. Plus there's no underhood pad to absorb noise, like in most cars (clearance issue above 'powerdome', plus cost savings I'm sure, as a pad weighs practically nothing).

Originally Posted by tony093

i was under the impression that S65 didn't need valve adjustment.

That is correct, but I have my doubts about the 'self-adjusting' part. Our valvetrain just seems better lubricated. I remember asking PencilGeek to scrutinize that claim, and he said all valvetrain parts looked the same as a 'regular' DOHC high-performance engine except a little lubricating hole on the tappets, so couldn't explain how they'd 'self adjust'. And he's been around engines. The good news is even DOHC engines without that system (Hondas) are supposed to last 100K miles without adjustment. Heck, even 'self-adjusting' drivetrains need to be checked/adjusted at 100K miles, since they have very little 'adjustment'. I wouldn't worry about that now.

[Stainless 45]

BMRLVR- Thank you for the reply - this seems to make sense. Sounds like valve noise and while I know the S65 can be noisy, It's the fact that it comes and goes with changes in rpm that made me wonder. As if the tolerances are changing as the hydraulic lifter "fills".

Of course the noise disapears as the rpms climb, and the car runs like a champ, just cleared 5K miles on it. Dealership has said it's normal, but I'm not keen to trust dealership mechanics. They seem inclined to guess at a problem and just throw parts at it hoping the complaint will go away. If there's not a rod poking out of the block then it's "within spec" etc.

[Ateam]

If its any comfort, every bmw I have owned has had a ticking sound problem! Think it is standard bmw protocol. Some cars worse than others. Currently mine is not a ticker but we will see!

[BMRLVR]

Originally Posted by elp_jc

Perfectly normal, by your description. Some engines are a little noisier than others due to manufacturing tolerances. By the way, must pushrod engines are superquiet by comparison, but mostly due to their iron block. Just listen to a Vette, which has pushrods but aluminum block (like ours), and they make much more racket than our cars. As engine heats up, and oil thins out, the noise is more prevalent. Plus there's no underhood pad to absorb noise, like in most cars (clearance issue above 'powerdome', plus cost savings I'm sure, as a pad weighs practically nothing).

That is correct, but I have my doubts about the 'self-adjusting' part. Our valvetrain just seems better lubricated. I remember asking PencilGeek to scrutinize that claim, and he said all valvetrain parts looked the same as a 'regular' DOHC high-performance engine except a little lubricating hole on the tappets, so couldn't explain how they'd 'self adjust'. And he's been around engines. The good news is even DOHC engines without that system (Hondas) are supposed to last 100K miles without adjustment. Heck, even 'self-adjusting' drivetrains need to be checked/adjusted at 100K miles, since they have very little 'adjustment'. I wouldn't worry about that now.

The S65 definitely don't require valve adjustments. Go and check the parts list for the valvetrain on the S65 (I am on my iPhone do I can't post the diagrams) , you will see the HLA listed but no where will you see valve adjustment shims like in all other of the M engines that require valve adjustments.

That little lubrication hole on the tappet is where the hydraulic/lash adjuster gets filled with oil....... That is how every hydraulic lifter/lash adjuster works. Inside the lifter/lash adjuster is a one way check ball which keeps the lifter full and in contact with the valve. As the clearance increases the one way check ball allows the lifter to fill and take up any clearance in the valve train. Sometimes the lifter will bleed down slightly after the engine has been shut off for a while and you will get some slight ticking on startup.

Another thing that can cause valvetrain noise is different oil viscosities. Since the 10w60 TWS is the only oil we are allowed to use it is impossible to tell if the inherent S65 Valvetrain noise can be lessened with different grades and or brands of oil.

[Stainless 45]

Thanks for the responses guys- I learn something every time I log on here!