E-type noises - normal or not?

[TrevS]

Hi all

Well I've done my first few drives in my 4.2 S1 and I have a couple of concerns with the engine noise. Generally the car drives really well, better than I had ever imagined, smooth and powerful and it handles really well but I have two noise issues.

1) When pulling to a stand still, hand brake, in neutral and releasing the clutch. The engine makes a louder whirring noise, if I apply the clutch it disappears .

2) At 2-3000 rpm the engine sounds like its rattling slightly, almost like tappets. When pushing on a bit to higher revs the noise disappears.

Does anyone have any ideas if these are normal noises or a sign of an issue?

Thanks

Trevor

[christopher storey]

The whirring noise is probably a noise from the release bearing, or it may just be that you can hear the gears in the box at idle in neutral, which is far from uncommon . It is not clear whether by " applying the clutch" you mean pressing the pedal or releasing it - if the noise disappears on pressing the pedal, this suggest it is merely the noise of the gears rotating , which is nothing to worry about.

As far as the rattle is concerned, this could be many things but if it is occurring under load then my favourite would be pinking , which again is quite common, particularly if you use 95 octane - in the 1800 to 2500 rpm band - and was present even when these engines were new . A check of ignition timing and mixture strength should tell you more , but provided it is not excessive I would not worry unduly at the moment

[PeterCrespin]

Agree 100% with Chris, although since an E-type is supposed to be driven under load regularly I'd dial out the pinking for sure if it still happens after a tankful of the best fuel.

[paydase]

Incidently, is it best to tune ignition timing with lower octane fuel to identify any undue pinking or not (timing being timing anyway?

[christopher storey]

The timing should be independent of the fuel used, but.... if with the timing set as per the manual, and the mechanical advance working correctly, then if you still get pinking it is advisable to retard the ignition by say 3 degrees static. It should also be noted that excessive advance is not the only cause of pinking : weaker than standard mixture also can lead to it

[tinworm]

We can all only guess as we cannot hear the noises mentioned - my own view is -
1) Gearbox first motion shaft bearing on its way out -( when you press the clutch pedal down this stops the gearbox rotating and so the noise stops )

2) IF engine is under load rattle could be piston slap ( as the piston comes to TDC and starts to decend the piston rocks in a (worn) bore and the skirt whacks the cylinder wall .
Of course both of these noises will vary according to wear and tear and the engine and 'box will go on for years before you need to do anything.

regards Barrie

[abowie]

1. Both my 4.2 gearboxes sound like cement mixers, and they have both been rebuilt. Normal. Usually the reverse idler gear which cops a lot of punishment.

2. Does sound like pinging/pre-ignition although of course it could be anything. If it is lower in the rev range and under full throttle that would make it more likely. I'd go through thoroughly and time/tune the car properly, run it on the highest octane you can get and see what happens.

[Candellara]

1, Release bearing & not uncommon
2, Cam buckets moving?

[PeterCrespin]

1, Release bearing & not uncommon
2, Cam buckets moving?

Sometimes advice or guesses are wrong enough that correcting them serves a useful purpose.

We are, of course, all guessing, but let's at least guess in line with the evidence:

1) The graphite release bearing has no moving parts and is silent. If it disintegrated or the clutch bearing surface had corroded badly it would only make a noise when there was relative motion, i.e. when the pedal was depressed. This is unusual for a graphite bearing, not common. The symptoms would be it made a noise when the clutch was depressed and be silent when lifted - the exact opposite of what we've been told. Educated guesses are fine, but going in the face of all evidence is either inspired or something else ...

2) Cam buckets are not affected by engine load, being totally passive and unaffected by throttle or combustion conditions etc. within the cylinder. It is conceivable that loose tappets in their guides might be more noticeable relative to other noises at certain rpm. So whilst it is not impossible that there could be a tappet component to the rattle, it too isn't a close fit to the evidence supplied to date. But then witness reports are sometimes incomplete or missing vital details, so who knows?

[mgcjag]

The release bearing has no moving parts but if the clutch is not adjusted properly at the slave cylinder then tbe release bearing could be in contact with the cluch slightly thus causing a whirring noise....when the clutch is depressed the noise stops bacaus the release bearing is pushed hard against the clutch

[PeterCrespin]

Good point. Never thought of that although I've never heard it. Serves me right for being definitive before breakfast...

[David Oslo]

I had a rattle within a given rev range (seem to recall it would come and go at idle revs) and would disappear as you put on the power. Used stethoscope to chase the noise to the front of the engine, and took off "fan" belt to cross the alternator and water pump of the culprit list. Problem ended up being rock hard (e.g. no longer rubber-ish) timing chain guides. So when the upper chain was doing a bit of harmonics at certain revs (light loading) it was rattling against chain guides that were hard as Bakelite, and hence made the noise.

[abowie]

The release bearing has no moving parts but if the clutch is not adjusted properly at the slave cylinder then tbe release bearing could be in contact with the cluch slightly thus causing a whirring noise...

When mine was maladjusted like this it caused a squeaking noise.