Noisy tappets 1.8 inj

Any advice welcome?
Our car 1982 1.8 inj , had an engine rebuild in 2007 and has covered less than 3000 miles since. Over the last few weeks we have noticed what we presume is the tappets getting louder? Sounds like a tdi!
Im taking it to the local garage on monday morning and would like advice before hand.
Is it likely to be just a case of them being adjusted? Are they adjustable? Any other ideas?  :?
All advice appreciated!

For all those that answered my stereo wiring problem topic, thank you - it took a bit of searching, wiring and soldering, but I now have tunes!

If you have the original engine fitted then it will have the 'solid' tappets fitted. This is a bucket and shim fitment and can be adjusted. If you've only covered 3K since the re-build I would take it back, it could be a tappet has slipped out of position or something but let them look at it. Do you know if the oil pump was replaced during the rebuild? Either way it needs to go back