164 oil leaks

Hello everyone, I know there are some 164 experts out there so I have a question for them. My 164 has 126k on it. When I bought it at 115k it was supposed to have had the 120k service on it. It turns out it did not (just a warning for those of you who use A-1 auto in Mountain View CA). So I had the 'external' work done, i.e. timing belt, cap and rotor, upgrade timing belt tensioner, etc, but did not have the valves adjusted. Now oil is fouling up the spark plugs. I was using Mobil 1 15w-50, but have switched to Red line 20w50 on the last change which was today. The valves click a bit too. So here's my ignorant question. Do I need a valve job? (not sure it was done at the 120k "service") or do I need a rebuild. This seems a little early for a rebuild give these engines are supposed to last much longer than that. Thanks for your help