I have just had a similar problem. No headgasket problem apparent, but overheating, starting when the bleed hose chaffed through on thr top hose clamp. Locl enthusiast garage wont touch a V6, they ducked out of the 72k service. Eventually got Tim Fry Landrovers to do it, they diagnosed and replaced inlet manifold gasket, didnt cure it. Then said steam coming from heads, so replaced the engine, cost £3000 in all. Every time you dismantle you risk breaking the neoprene hoses that go brittle with age/heat, some are expensive too! Bleeder hose is £18! Even after i got the motor back, I still had a steaming problem at idle, had to replace the expansion bottle and cap. Surprise there, expansion bottle and cap about £7 when simple bleeder hose £18! I didnt dare ask what the main stealer would have charged.
