When I left school I got a job as an apprentice mechanic. We service a fleet of cars, occasionally a jag or something intresting but mostly viva,s , cortinas and the like.
A service then took a while, you would drain the oil , remove the air filter, remove the rocker cover , clean the cack out of the cover. Remove the spark plugs. turn the engine to different postions and check each tappet for clearance adjust and lock as needed. Replace the plugs. Put a new gasket on the rocker cover and refit the cover. Then check the points , usually replace them along with rotor arm and distributor cap. Put everything back together with a new air filter and the oil replaced. Wipe the thing with a oily rag and hope it would start.
Then fluids would be topped up, washer water , battery and coolant.
Next was the brakes, discs were scraped, copperslipped and cleaned of dust. Drums were dismantled cleaned , rubbed with emery and contact points lubricated and after several attempts, put back together.
Tyre pressures were checked the car test driven cleaned inside and out. The keys handed back to the manager for another 8,000 miles of service.
Of course cars are a lot better now and the bits that arent better are disposable thanks to our chinese cousins.
So a service means "change the oil" a major service means "change the oil, air filter and perhaps plugs". I do sometimes wonder if cambelts are only used to provide the dealers with a nice revenue source. Surely not.
I believe that ignition is now electronic and certainly on most moderish cars tappets are hydraulic, I could be wrong but I would expect them to be on your V6.
My car suffers from a tappet type noise , only it doesn't speed up with revs . Advice on here is that this is somekind of fuel vapour doodaa that is just noisy but not easily fixed.
If the fault developed after the garage accidentally service it, you should ask them to accidentally fix it
Was it the same garage that replaced the camshafts ?
best of luck, keep that v6 turning.
Is anyone still reading ? you should be getting some work done, not reading a post this long