Engine "tappet" noise

[fergusor]

Hi Guys,

I'm a bit concerned about my MCS, I'd like some advice please.

I had to add some oil to my car about a month ago (1 litre) and all seemed to have been fine.

I drove down to Leicestershire from Derbyshire today, and back, and again all seemed fine. I stopped off in Tesco to get some food and when I started the car back up again (about 15 mins later) the engine sounded really tappety like it had no oil. The oil light hadn't come on at all over the course of the day and wasn't on when I started it up again.

I wasn't sure what to do so I decided to drive home (less than a mile) and by the time I got there there was no tappety noise coming from the engine. On the drive home there was no loss of power at all and again no sign of the oil light. I went out to the car again about half an hour later and started it up but it seemed fine.

Can someone shed some light on this and whether I should take it in? I haven't been able to check the oil as it was dark by the time I got home so will check it tomorrow. But any help in the meantime would be most appreciated (I'm really worried about it... it's done less than 10,000 miles, almost a year old).

Thanks,
Richard.

[ScienceGuy]

If it were me, I wouldn't worry about it.

• You are checking the oil and it didn't get more than 1 liter low.
• The oil-pressure light never came on
• You don't see any performance changes

So chalk it up to a slightly noisy valve train and hit the road to enjoy yourself.

Car engines make noises. Some make more noises than others, but that doesn't mean
they are about to fail.

[fergusor]

UPDATE:

I started the car this morning and it made a slight tappety noise for about a second then settled down. So I took it out for a run, parked up and checked the oil after 5 minutes and it all seems to be OK.

I think I'll contact the dealer tomorrow and see what they have to say... I'm a bit worried it could develop into something else.

[obehave]

Quote: Originally Posted by fergusor (original)

UPDATE:

I started the car this morning and it made a slight tappety noise for about a second then settled down. So I took it out for a run, parked up and checked the oil after 5 minutes and it all seems to be OK.

I think I'll contact the dealer tomorrow and see what they have to say... I'm a bit worried it could develop into something else.

I've found mine is a bit noisy if I don't change the oil soon enough.
Starts around 5K miles.

[SiBradbury]

Quote: Originally Posted by fergusor (original)

UPDATE:

I started the car this morning and it made a slight tappety noise for about a second then settled down. So I took it out for a run, parked up and checked the oil after 5 minutes and it all seems to be OK.

I think I'll contact the dealer tomorrow and see what they have to say... I'm a bit worried it could develop into something else.

A lot of cars do this, especially ones with hydraulic tappets. Imagine a little plunger that uses oil pressure as a spring. Until the oil pressure builds up, the tappet rattles a bit. It takes a second for the oil to circulate and build pressure in the upper part of the engine and fill the tappet.

It's more common to hear the tappets when an incorrect oil has been used, usually a thicker version will take longer to circulate properly and work its way into the tiny oilway in the side of the tappet.

A commonly made mistake is when people put a thicker oil in their car thinking it will quieten tappet noise when in fact it will make it louder because its like trying to force treacle through the tiny hole that is the oilway.

If i've done a rubbish job of explaining all that, go here instead!:
http://www.volvoclub.org.uk/tech/Hyd...ic%20tappet%22

PS i'd like to stress that I have NO involovement with Volvos whatsoever! Blame Google!