Engine sound of the 456

Hej,

I just want to get your ideas on how the 456 or type 116 engine shall sound.

During Idle it is a little rattly but this is due using non hydralic valve lifters which is ok (it has got 48 valves so it is never going to be quiet).
During running/load I feel that the engine is especially rattly between 2-3k rpm but beyond that it sounds smooth and howls.

I read in a magazine the other day in which they tested the 612 (new car) and they complained that it sounded hammery at these specifc revs 2-3k, the 612 do use hydralic lifters so it is not coming from the valvetrain.

Any reflections comments?

Mvh
Joakim

 

Hi,
At idle there is a noticeable mechanical noise coming from the front part of the engine down low.
I am not sure about the origin of it, but I was told it comes from the drive of the lube oil pumps.
Since I never took one of these engines apart, I cannot say that is actually the source of it.
Not much clatter coming from the valve train though.
Once under way, the exhaust sound takes over and above 3,000 / 4,000 rpm it really howls.
A.

 

Joakim, hydraulic or not, it should be quiet on the top end. It has some mechanical noise but if it gets to the point of 'rattly' then you probably have excess valve clearance on a few valves. Which is not uncommon to occur if an engine has been opened, after a few heat cycles everything settles down; sometimes valve clearance can be off a little after that. It might be just that.

The other noise is more worrying. Normally I am quite keen on noises an engine makes and I did not notice any before on my car, so I would not assume it to be a normal thing. A rattle which is only there under a light/moderate load and moderate revs might indicate a connecting rod bearing issue, so be careful indeed. I will be driving mine later this week and will pay great attention to any present noises and report back.

 

I know but I exchanged them all during the rebuild, tolerances were put to factory spec and everything has been assembled to spec, I might be chasing ghosts who knows..

 

Did you change the oil pump drive chain? It is a poor piece of design as it has no effective tensioner, just some guide plates. The noise can come from a slack/worn chain slapping against the guides.

The good news is that it wont break, just because it is noisy. It can be replaced with the engine installed.

One of the first things I did on mine, but the noise didn't go away completely, it is (just) noticible when cold.

 

Joakim- Replace the center muffler/resonator with a couple of pieces of straight stainless steel pipe and you will not hear those noises quite as much. Much better than the white noise we used to cover classified conversations. Yours will be V12 music.

Taz
Terry Phillips

 

Sometimes Man's fears causes Man's biggest suffering. Once got a similar bearing repair on an Alfa Romeo that I bought second hand - let's just say the owner wasn't exactly accurate on its history. After that fix I was very keen on noises also. Yes I thought I heard some, and yes, after a few months finally got sufficiently paranoid to the point of reopening the engine and finding completely nothing wrong.

The oil pump chain is indeed a possible candidate, the key here is whether there is load on the engine or not when it's heard.

If you're seriously unsure and are at, or could get to, the point of opening up the engine, I would first think of a measurement method where you would measure the height of the piston deck with a micrometer through the spark plug hole. Should not be too difficult to engineer a screw-in thing that houses both a thin pin driving a micrometer and an air connection to make it possible to vacuum resp. pressurise the combustion chamber, all this to measure vertical piston movement. Serious play in bearings would show is my guess. Anyone feel free to shoot holes in this idea.

Taz: Completely agree

 

well as I said I did change all bearings and made sure they were put to factory spec, I also measured (a professional did, verified it afterwards) the cylinders, pistons, crank (main bearings were regrind), changed the big ends, small ends, replaced oilpump chain and tensioners etc plus all ballbearings in the crankcase.. The engine sound reasonable during idle when fully warn and good above 3k rpm but in the intervall 2-3 k i sound rattly, like an old moped in my book (yes it is very vague but still).
The valves are going to be re-checked, I was asked to drive some 1500km and then reshim if needed, I know some will need shimming because of the clatter sound.

I also suspect one of the catalyst as I know one is bad (melte3d in the middle), the idea is to replace the core.

And yes I will remove the central muffler to get a harder exhaust note, I will be interesting how that will match up with my Fuchs end pipes, probably quite loud.

 

quite funny, you acctually can hear the messy sound of the V12 in this clip by a fellow FChatter.. so I guess I might be chasing ghosts

http://ferrarichat.com/forum/showthread.php?t=323806

 

If yours sounds like the one in that clip, then yours is working normally. Not that that is a reliable check though, by the time a crank bearing is audible at idle then its time to run as it is about to blow .

But Joakim, a "messy" sound? Has the world now come to the point that the beautifully complex mechanical sounds of a thoroughbred V12 are described that way?

On another topic, I do hate the fan noise on these cars, has anyone investigated in replacing the SPAL units with more modern ones with a better fan blade design?

 

Yes, Spal-USA is listing some fans that should be quieter and possibly even move more air.
They should be a direct replacement of the OEM units.
However, I have not tried any of them yet.
I am pretty sure Spal the-mother-company has them on their list too.

 

Messy yep compared to the Alfa V6 (24v version) and my boxter unit, these engines both sound tight and delightful, the ferrari unit is a peach over 3k rpm but sounds like a massey fergusson below that but hey is a ferrari unit really meant to be running at idle speed??

 

I have a 95 456GT and love the sound of the V-12 but hate the fact that at idle all you can hear is the annoying whine of the cooling fans. I don't know of any other car that makes this much fan noise.

Does anyone have actual experience in changing the cooling fans to a quieter design?

 

I got the chance to drive about 300km with the 456 this weekend and took it. My personal 456 mileage has now risen to 943! With this thread in mind I did do a little listening along the way. Not too bad of a fate .

At idle it is totally quiet, it just has some white noise at the front from all the parts turning but that is it. As soon as the fan comes on it screams well louder than the engine . That is definitely something I am going to work on.

At speed there is a definite rumble when urging the car below 2500rpm, more like a deep slow growl, but I would not describe it as hammery. It's not a diesel, after all! As soon as a Ferrari V12 sounds like a diesel you know you have an issue.
I did once have the feeling when flooring it at lower rpms I could hear some pinging, maybe I should use 98 petrol despite what the manual says? And of course she screams above 3000 rpm, beautiful.

No real noises that would concern me, and I am confident enough to know, I diagnosed quite a few cars up till now. No 456 that I have heard sounded like it at all. Joakim, perhaps we should meet up one day if I'm in Sweden. I don't have plans at the time but as soon as they develop I'll let you know.

The drive this weekend did have one drawback, it was cold today and it revealed that the oil thermostat on mine needs replacing - the oil remains way too cold when easy on the car (speeds up to 140kph) and as a result the water stays behind also; the water thermostat has recently been replaced but this one has not. Costs quite a bit though for such a little and low-tech part. And why, one asks. Oh wait, the prancing horse, yes, how could I forget...

 

Not to divert from the topic at hand, but once you replace your thermostat, please tell us how you get on.

I have the same issue with my car; when on the highway even on warm days the oil temp is in the 170 range. Significantly lower in spring and fall weather.

I tested the thermostat in an oil bath and found it hit the temps in the manual; I finally replaced it anyway and the problem remains. It is driving me crazy at the moment - I have been looking to ensure the lines are routed right and the thermostat itself was installed correctly and I can't find the issue...

 

I would say when cold is sounds like a turbine totally quiet but once warm you do get the rocking sound just as the car in the film clip and some valve clatter.

I'm not so sure I'll care about the hard noices the engine make under 3k rpm anymore as I have disassembled everything and measured that cylinders, pistons and big ends were within tolerances, the rest of the bearing were changed and the mains of the crank bearings were regrind so I guess I'm just not used to 456 V12s, my old jag v12 was a lot quieter though..

 

I believe at idle a 456M should sound about like this ...

[ame]http://www.youtube.com/watch?v=yZGfxY8hNRI[/ame]

 

Joakim, you're comparing two very different breeds there . It is possible that the V12 Jag is quieter, I do not have hand on experience with them, only twelve cylinders I have experience with are the 512TR, Miura and Murcielago engines. A Miura V12 can be very quiet as well and probably most closely resembles the Jaguar design; but a Murcielago is somewhat similar in the soundtrack to the 456.
The difference you experience is likely a combination of the multivalve design and the high performance pistons on a 456, which are radically different with very small skirts; leading to lower friction but also more piston rocking and noise.
My suggestion would be to stop worrying and start enjoying your car.

Dean, that is an interesting comment, before I will be exchanging the oil thermostat I will do a check of it first after your experience. Come to think of it after reading the manual it seems it can only be stuck open if the wax element is seized. It would stay closed if the element would be broken, and the oil would overheat. Perhaps the spring that should close it again has become weak and is the culprit. I will try that first.

 

Yes, this is how they sound "Lazy and heavy rocking", on this one you can also clearly hear a badly shimmed valve.

 

I'm trying I just need to sort the darn flicking warning lights...

I was coming to that, the 456 piston is really short and it will move about a lot at slow speeds, the sad thing though is that these engines really spend the major part of their life in this region as the car is very long geared and the speed limits are so awfully low over here.
As I said I'm just not used to the proper noises it shall make, the previous noise was a bearing fault which now has been rectified, and I guess Ferrari didn't really care about slow speed noises when they made this engine it was all about full throttle!

Tonight I'll perform a checkup of the valve play and timing since my engine now has full a full 1500km since rebuild, that is gonna be interesting.