Boiled 360

put your thermostat back in and see what happens. running with no thermostat can cause an engine to overheat because first the coolant don't absorb the heat from the engine because it is circulating too fast. After awhile the coolant will begin to absorb the heat and then it will show up on the temprature guage as running hot but will never cool back down because it is circulating so fast through the radiator that it doesnt' have time to cool. So since your in Alaska drop in a 195 degree thermostat and you should be good.

Also there is a possibility that you have a crack in it somewhere.

I agree with le, the thermostat is required.

yes the thermostat will help. also, what kind of cooling fan do you have (clutch style or flexblade?) if clutch style the clutch might have went out on it, if fixed blade, did you put it back on properly, if it is on backwards it will draw air away from engine instead of drawing it to the engine.
are you radiator hoses collapsing by chance? this will sound stupid, but by chance did you put a rag or something in the radiator hose to stop it from draining while the engine was out or lines unhooked? if so did you remember to remove it before everything was hooked back up?

just a few thoughts for now

eric

ps: how good is the water pump?

OHhhhhh ! and the other "Well DUH" we forgot to mention- Is your fan shroud in good condition. It doesn't seem like a big deal, but it IS.

Oh man i hope you didn't overheat it breaking in the cam, you are supposed to run it without a stat to break the cam in but your also supposed to run the hose in the motor and let it run out, im guessing this is why you left the stat out, but if you got it good and hot while breaking the cam in your chances for hurting the cam are greatly increased.
This is all just speculation since it wasn't very Specific as to when it started running hot , how long, during break in after break in you guy's gotta get Detailed, not just you but everyone asking a question

When you put your head gaskets on, did you use any gasket sealer? If you did and it spread out too much it might have blocked the coolant galleries.

yes, like marty said, be more detailed. does it overheat at standstill idle, and cool down at higher speeds? you need the thermo now most likely... and all these other posts are good advice, including the "duh's", check them out.
derek

It got hot during break in, but it boiled after i stopped it. The gauge was on top in the end of the break in. I haven't been able to drive the truck around yet, But it seems like it gets hot very fast. Didn't forget any rags, the waterpump I used during break in is old and started to leak after Break in, but I got a new one but haven't tried it yet. Didn't use gasket sealer because I was told the Felpro gaskets didn't need that.The fan is good, don't think I mounted it backwards. There's no cracks in the sylinder heads, But the funny thing is that there were a crack in one of the old heads but it didn't overheat then. But thanx for good advises anyway.

Yesterday one of the valves broke and fell in to the sylinder and stopped the engine. Fu%¤#%¤#

and by the way I live in norway. and its damn cold here

Ok i thought you lived in Alaska cause your info under your screen name said AK. Sounds like you get to pull the engine apart. The excessive heat may have froze one of your valves up breaking it. This next time around don't be cheap and use a brand new water pump, new thermostat and new fan clutch.

Check your cam see if you didn't hurt it, when you break it in this time you can leave the thermostat out and this time run the hose this way the water is always cool, then you use the hose to keep it at a regulated temp no higher than 190, during break in 200+ temps can be a problem

I left the thermostat out because I believed that then the engine would never get operating temp and always stay cool, and be sure there were no air in the engine that would cause overheating, but I might be wrong. Evildriver3 what do you mean by "run the hose" and that stuff? How do I know if my radiator is bad?

When breaking in a cam it's safer to leave the stat out then find a overheating problem while in the middle of breaking the cam in, so what you do is take the hose (your garden hose) and let it run in the radiator and the upper hose stays disconnected.

Then when you are done breaking the cam in you take a new thermostat drill a 1/4" hole in the restrictor part of the plate next to the actual valve that opens then put the stat back in the motor and fill the radiator start it up refill the radiator and overflow and go on your merry way flooring it and feeling the new effects of your cam

kongeddie said:

I left the thermostat out because I believed that then the engine would never get operating temp and always stay cool, and be sure there were no air in the engine that would cause overheating, but I might be wrong. Evildriver3 what do you mean by "run the hose" and that stuff? How do I know if my radiator is bad?

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You're right in that the engine will probably stay cool. It'll also wear out quite a bit faster. Engine wear increases dramatically at temps below 160 degrees.

another thing is too much antifreeze wont cool the same as a 50 50 mix of water an anti freeze. the anti freeze doesnt transmit the heat an suck it from the block like water does

Evildriver-3 said:

Then when you are done breaking the cam in you take a new thermostat drill a 1/4" hole in the restrictor part of the plate next to the actual valve that opens then put the stat back in the motor and fill the radiator start it up refill the radiator and overflow and go on your merry way flooring it and feeling the new effects of your cam

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Whats the deal about the hole? what's it good for?

Got the engine together yesterday, just had to put in a new valve. there was a little scratch in the actual sylinder. whatever. the thing i love about american made engines is
that they are machined so "bad" but it works like hell anyway!

I love american cars!

yeehaa

You drill the hole so you don't get air trapped it bleeds it off, just drill the hole, the hole is drilled in the restrictor part of the thermostat, the flat ring surrounding the actual valve