My 454 Vortec has been overheating recently (running around 210-215 regularly). Until about 3 weeks ago, the motor ran religiously at 195-200. Sometimes when i stop however, my temp will spike to 225 until I begin movign again. I have replaced the thermostat and flushed my radiator with no luck. Three days ago, I found a small puddle under the right side of my vehicle near the lower radiator hose, but when I looked deeper I found no leak. I have yet to check my water pump for fluid, and I don't know what else to check. I have dirven the car twice since then (gotta get to work) and have not had any fluid draining from my vehicle since (so far). What could my problem be?

 

Ive had three big block sububans and every one of them ran on the 200 and then sum area in the summer but never got to the over heating point except my 92 which had 275000 on it when the rad hose blew. Check the coolant lev see if its full drive let it sit and then see were its at.

 

Perhaps the water is coming from the overflow tank from too much pressure being built up in your cooling system. I bet money on the fact you have a plugged radiator. Drain a few inches of water out and look down in there. With the dexcool and the small high efficiency radiator, those little "barnacles" in there are robbing you from precious cooling.

 

the big block i used to have (see sig) started running hot, i put a 4-core radiator in it, 160 t-stat and 05 tahoe electric fans after that it ran at 150-160 in the texas heat, in traffic with the a/c on and one fan running

 

I have been looking at radiators for the last few hours and have a few new questions. does my radiator have a trans cooler? or is it mounted somehow in front of it? second, do you have any suggestions for radiators? i do tow so I am looking for increased cooling, but I also want a radiator that is basically a drop in unit as well.

 

to determine if your radiator has a trans cooler look on the passenger side of the radiator, is you see 2 small metal lines running into it, it has a trans cooler built in. i think i called 1-800-max-cool for mine, it was a couple of years ago so im not 100% sure thats the number. depending on what your budget is you might call be-cool (or call summit racing and ask about them) but they are going to be pricey

 

I went to Summit Racing's website and radiators run from 250 all the way up to like 900. Any recommendations for a radiator that I will use on a mildly built motor and tow up vail pass?

 

Update, while driving today, my car started running a little hot (210ish) so I decided to pop the hood and on the left side of the block, it looked as though a small amount of fluid had leaked out of the block. It look orangish like DEXcool, but it was too hot to touch so i couldnt really tell since I couldn't get close enough to smell it. Blown head gasket maybe? Seems like my small cooling problem has turned into a large project all of a sudden

 

Depends on where you saw it.
Possibilities from "not so bad" to "worst"

1. Leaking thermostat housing or upper hose
2. Water pump
3. Head bolt
4. Intake manifold gaskets
5. Freeze plug
6. Head gasket

I had a hard time deciding if the freeze plug or the head gaskets were worse. Swapping a freeze plug with the block still in the frame can get pretty ugly...

 

I going to take a couple pictures tomorrow and post them so you guys can get a better idea. Maybe it will be easier to help then.

It isn't the thermostat housing or hose, the hose is clean and the thermostat was just replaced, so we'll see.