Hydraulic tappet noise

[123-jn]

Hi folks, I have a 1.9 DG 1989 which has had an oil change and coolant change but despite this if I leave her for more than a day without running, next time I start her up one of the tappets knocks for about 3 miles before it shuts up. I thought it was always the same one but today it was one on the other side. I'm using a 15/40 multigrade semi-synthetic. Once it shuts up the engine runs much smoother and sounds really sweet. Here is the question- IS this normal? My Picasso diesel sometimes does it but shuts up after only a few seconds.

[kevtherev]

yes it's normal for higher mileage engines.

you may want to consider adjustment, despite VW's claim that they are maintenance free, they are not.
you might want to read this, it's all you need to know

http://www.ratwell.com/technical/HydraulicLifters.html" onclick="window.open(this.href);return false;

[Ian Hulley]

I'm using a 15/40 multigrade semi-synthetic.

Really ?

[Mocki]

Like Kev says, check the lifter adjustment, and change the oil and filter again.

[123-jn]

Thanks Kev that's a great article. Now I think I get it. I will change the oil again and check the lifter adjustment 1.5 turns after contact. I see everyone seems to use mineral oil not semi synthetic ? perhaps I'll get some.