2ltr aircool tappet problem

[camper]

I replaced valves on the cylinder heads refitted heads. bleed tappets and adjusted ie two turns refitted engine.Its been running took it out for a road test today.Noise developed from no 1 cylinder bit of of rough running. Pulled off rocker cover discovered exhust valve tappet has slid across on the rocker shaft partly on valve spring .My concern is what is causing this?.I loosen shaft nuts and tappet has come back on to the valve stem.Any ideas thanks

[toomanytoys]

Thats not the tappet, thats the rocker...
has a spring broke? there are springs and shims keeping them in positon.. (IIRC)

For hydraulic tappets, only pre load by 1/4-1/2 turn from "no play", 2 is too much apparently.. (well, for the wbx it is and they have the same hyd tappets!!)
or if you like, run with no preload for a bit, this will ensure they are fully bled..

[camper]

Thanks for your reply.There are only springs fitted on all the rockers .In my haynes manual it shows the shims plus spring.The spring is not broken maybe there should be the shims.Regarding to adjust it appears one and a halve to to two turns is stated in the haynes but you may be right.

[camper]

Found out why sticking valve.Slightly bent on the stem replaced valve.