valve noise at startup for 1 - 2 seconds?

[svwilbur]

We have a 1990 240sx S13 SOHC with stock KA24E engine. Manual transmision, coupe.

It has 144K and was "rebuilt" according to previous owned 50k ago.The engine runs great and pulls hard and has smooth excelleration.

But when it is started I get about 1 to 2 seconds of what sounds like valve noise tapping/rapping toward the front of the engine. Could be timing chain maybe not sure what it is.

But it makes a rapping sound for a second or two then goes away completely and runs quiet and smooth from then on.

It does it from when the engine ignites and while cranking and for a bit after the key is released so I do not think it is the starter.

I have read that sometimes a part or the timing belt tensioner can get loose/broken off and rattle around but this is noise I have is real consistent. Each start I think. It may not do it on some warm starts. But most all starts has the noise. And never after it has been running for 2 or 3 seconds.

Kind of like it is not getting oil to some of the front valves right away.

Should I be worried?Any recommendations on additives or resolution?It has a new filter and clean oil but still makes the noise.

[locoluna825]

dont be worried thats normal for the sohc's, the tapets on the rocker arms dont have enough oil in them when it first starts up so as the oil pumps up in the engine it goes away, mine does the same. the only thing i can suggest is a HV oil pump , but that noise is nothing to be worried about, unless.... it doesnt go away hoohahaha

[Wc240]

i second that. the lifters and the tensioner need oil pressure and it takes a few seconds for that. the only real time you should be worried is if it takes like... a minuete for the sond to go away. i havnt heard a single sohc that doesnt have this sound, rebuilt or not