- May 22, 2017
Okay so i'm kinda lost at the moment. Finally fired up the 455 tonight...... runs great, no smoke, weird noises or anything..... until its ran a bit then it starts over heating, i've checked the block, radiator, hoses, water pump, everything i can think of. even tried running it without a thermostat just incase it was stuck or the block was vapor locked. going to do a cooling system pressure test tomorrow as well as a compression test on all the cylinders... i've got no oil in the coolant, and no coolant in the oil so i'm kind of lost. Its an Edelbrock 2151 RPM intake and E heads. Now if the exhaust crossover plugs havent been installed, would that cause the coolant to boil? when t starts to overheat i have checked it twice with a laser thermometer and both times, the block and heads have been around 180 but the intake along the front by the thermostat housing, as well as the back passenger side coolant outlet are well over 230. i've been running the engine on a test stand with a 3 row aluminum radiator with dual 12" electric fans and shroud. The radiator and fans seem to be working right. on at 185* The temperature at the Radiator outlet going to the water pump inlet stayed around 140-150 until the temperature spikes at the intake and then next thing you know, you are looking at 230* and a geyser out of the radiator and overflow, but before the temperature spikes, there are no signs of compression in the coolant or any aeration like there was head gasket issue. Has anyone ran into this before? possibly a cracked intake or i just need to plug the exhaust crossovers?