Hi, I have just bought an early FH12 (1994) which I intend to use as a show truck, when I get time to do the bits and pieces on it. Not had one before and cant seem to tilt the cab, have turned the lock valve in the nearside step clockwise but when i jack it, it seems to have some resistance. I know on other trucks you have to take the grille off, or move the steering wheel. Can anyone tell me if I am forgetting something. Thanks.
you dont have to take the grill of there at the back of the cab there is two cab springs the cab locks sit on these some times these locks stick they are supposed to relise wen you start to pump the cab up give them a tap with a hamer while some one jacks the cab uo also check the oil in thcab pump
The pumps are crap on them, make sure it is full and check the pipes that go into the cab locks on the rear cab mounts aren’t leaking or sticking. If its a globetrotter it might have an electric pump as well which is operated by a switch on the dash and another switch on the n/s wing
Series 1B (facelift model) sounds like. When you pull the handle at the back of the cab it shuts off a valve that closes the hydraulic circuit to allow the cab to raise. Similarly when you let it down, when the cab mechanism reaches that point is drops onto it’s mountings.
Is it a CD trim? if so there will be a switch near your right knee (if right hand drive) for the cab tilt.
if you send a pm (personal message) to member Y111RDF he may be able to help you with the renovation, as he has an ex Ralph Davies series 1 that he has done up.
That’ll teach me not to read the thread properly…FH12 not F12…DOH! I’ll shrink back to my bottle of Rioja! 
Thanks for all your comments, I will check it out. It doesn’t have any other switches on the dash, but on the rear air suspension control, ( control on a long wire ) there is a second position on the switch, not sure what it for.