Hy Will79big10, why did you have to retime it in the first place, was the distributor hold down loose? If it wasn't loose one of the few ways the timing can change is the timing chain moving on the camshaft gear as Wrenchbender said check how much slack there is in the chain, with the distributor cap off move the crankshaft and make sure the rotor responds immediately, if not it's chain and gears time. Hope this helps.
