Coolant overheating and leaking out a small vertical hose at rear of engine

[Clua Lurker Find all posts View Profile Close Clua]

Just had a new engine installed, 450000 out of the old one on duel fuel LPG. Normally travel 1000K per week. New one went beautifully heaps of power for the two weeks it has been installed. Today,after a half hour drive up to the Tablelands she was boiling and hot gas and coolant was coming out at the rear of the engine, it seemed to be coming out of a small diameter vertical hose right beside the firewall. Water was visible on the road. I refilled radiator after waiting for it to cool and got half way home [15min, down the mountain] before she spat and boiled again. Put about 5 litres of coolant in, starting to boil again after driving 10 min. Now home and wont be driven again. The gauge wasn't registering until the boiling had really started. Nothing at the radiator end was boiling; all the heated water and steam was coming out of the back of the engine.

On the old engine the last welch plug next to the firewall was leaking and we, kept the car going with bars leaks. Could we have blocked up the cooling system somewhere other than at the radiator and now it is leaking to release pressure at the weakest point? Could we have blown a welch plug? Worse, could we have cracked the block? We have put in a new water pump and timing belt with the new engine, cleaned radiator fins, new radiator cap and new thermostat. Radiator was renewed about 3 years ago but has on occasions needed fins cleaned of grass seed from the paddocks. Automatic transmission is going fine.

[Pabloprado Lurker Find all posts View Profile Close Pabloprado]

That bars stuff blocks up radiators and whatever other small holes it can. Probably should have cleaned out the whole cooling system before putting in the new engine.