Metallic Clunking Noise from Engine on Start-up

CrazyChemist_2

I notice that whenever I start my car (97 (P) Almera) in the morning or after a few hours idle the engine gives a clicky metal type sound, a bit like a diesel engine. Only thing is that it's a 1.4 Petrol so I'm a little worried about this! It stops clicking and clunking after about 1-2 seconds.

The oil level looks fine and the oil and filter were changed around 9 months ago. It's been happening for a while now but earlier today it was quite bad which is why I'm here now asking the experts

CC :beer:

Update

This is the text of my email to HJ - it's more descriptive than my initial post:

Dear Honest John,

I have a 1997 (P) Nissan Almera 1.4 Petrol. Mileage is ~ 55,000.

When I start it up in mornings, I sometimes notice the engine initially sounding like a diesel engine and then quickly fading away to give the normal engine sound. This happens for no more than a second after relieving the ignition key. It happened again today as I started it up to put it in the garage for the night and emitted what I can only describe as a metallic 'clunk' sound.

I have noticed the oil light staying on for longer than usual and sometimes the noise does seem coherent with the oil light remaining on for a half second or flickering for a half/full second.

This happens more often if the car has been left for a couple of days in the garage without being used. In case it helps, I do low mileage (~ 6,000 per annum) and it is mostly city driving with about 1000 mway miles. The oil and filter were changed in April 2005.

Wig

Gawd knows, you'll have to try a better description. Does it happen every time you start? If so stop at a garage and ask them to listen to it.

Also try Honest John backroom/technical but you'll need to work on the description I think.

It could be your tappets/hydraulic tappets just making a little rattle - nothing much to worry about.

tomstickland

Sounds like tappets to me. They are hyrdaulic and take a few seconds to pump up, engine sounds like a Diesel until then.

vansboy

Guess the same as Tomstrickland, it's a bit cold, so the oil takes that tiny bit longer to get all through the engine, on start up.

If it IS this, it's not a real problem - though you might like to get someone else to listen.

& a fresh oil change with 10/40 spec wouldn't be a bad idea.

VB

CrazyChemist_2

I've updated my first post with the detailed email that I sent to Honest John.

I emailed Honest John and got this reply:

If it "sounds like a diesel" then the oil is not pumping up the
hydraulic tappets because it is not getting to them because either
an oilway is blocked or more likely the non return valve in the
filter is not working.

If it's the timing chains, then you are in severe trouble from
running the engine on dirty oil.

HJ

Hydraulic Tappets eh? So if it's making these noises, is there any damage being done? It happens every time during startup especially when out in the freezing cold but also when garaged for the night. :rolleyes:

I don't know much about the technical nature of cars and this may need me to take it back to Kwik Fit for a new oil filter if it is the non return valve which isn't working.

Oh and could someone tell me what is meant by 'severe trouble' from the timing chains?

Wig

Depends if you have timing chain or timing belt. If it is a timing chain and the noise is the chain then your engine is about to go pop.

Does it happen when the engine is warmed up, turn it off, then tart it again. If it doesn't happen > more likely to be hydraulic lifters (tappets) if it does happen > more likely to be something else.

vansboy

There isn't a way to check the filter - so the oil n filter change, I suggested should be done.

Plenty of offers at Fast Fit places have offers for oil changes, so don't overpay at KwikFit. In fact, you'd be better off building up a relationship with a smaller independent garage, 'cos they'd be more helpful for other problems, you might have - rather than relying on the limitations of a fast fit.,

VB

CrazyChemist_2

I've recorded a sound file of the exact noise - I started the engine once, from cold, which is the first one on the file. Then I started it again twice and it didn't make the sound. Maybe this will help the diagnosis.

Wig: It happens only when the engine has been off for a few hours usually when cold. If you listen to the sound file it will only happen the first time.

Car.wav (0.9MB)
(It's probably best to right click on this link and click "Save Target As" and save it on your desktop to listen with Media Player/any other player)

vansboy

Thats a clever way of doing it!!

Sounds like the problem isn't anything to worry about - just as we suggested, oil drained from the 'top' of the engine, just getting back up again. But do think of an oil change.

Wig

lifters, nothing to worry about imo, you could flush it out and renew with the reccommended oil, if you know what oil is in there try a higher viscosity e.g. if you have 10/40 try 15/40.

Why was the engine stopping? was that you turning it off?

CrazyChemist_2

yeah I turned it off twice to show the difference between cold start and a non-cold start.

This is a fairly recent problem so maybe it is worth changing the oil and filter. Perhaps using a Nissan Genuine filter would help? Although Kwik Fit say that the one they use does have a non-return valve on it... not sure who to trust.