Im working on a 1966 mustang strait 6 it was over heating so we replaced thermostat and water pump i filled the radiator started it up it and it got warm could not see the coolent moving in radiator reved the motor up as soon as i let off the gas coolent pured out the top of radiator and still wants to over heat any ideas im thinking head gasket but not for sure

 

when did it start doing this and how hot did you get it when it first started over heating?

 

So a friend wanted me to do a tune up and get it running better so he could put it in a parade it was running like sh*^ as i get started i notice the air filter was up side down i pulled the plugs they were so black and the build up on them im amazed it ran at all changed tthem and wires fuel filter pulled some gas out the tank was really cloudy and grose draind it got fresh gas in it it ran way better radiator fluid didnt look good but not really bad he drove it a few hrs the next day then went a couple miles in the parade it stared running worse few minutes later steam and coolent all over under the hood he got some water in it after a bit got it home thats when i did the thermostat and water pump like i was talking about in the first post

 

does the engine oil have any water in it? Are you able to observe any coolant on spark plugs or inside the combustion chamber?

It likely either has a plugged up radiator that isn't flowing well or a blown head gasket secondary to a plugged up radiator.

Does it ever act hard to crank over like the battery is low on first starts? Does a bunch of white smoke come out when it does start?

 

So i swaped out the radiator and it seen to be working good any ideas on so i did the tune up plugs fouled bad some were dam near soled chunk and it leaves a black mark under muffler every time you rev it up how to blow all that **** out