I just looked over all the posts on this and one thing I didn't see mentioned is the fact that GM uses two different water pumps. One is the normal "forward flow" and they also use a "reverse flow" pump. The difference comes from which direction the serpentine belt turns the pump. I am not sure how to tell the difference between them by looking at them on the engine. I know that if you have them off the vanes in the pump are pointed in differnet directions. Anyway the point is that if you got a reverse flow pump on a forward flow system or vise versa it would ariate the coolant and cause overheating as described in a previous post.

Just another thing to consider.

Hi. The pressure is fine, but im not sure about the reverse water pump thing. Ill have to check that. I got the pump at advance auto, but mabey they gave me the wrong one. ill check that. thanx

Nope, it not the pump. Back to the drawing board.

Try running it with no thermostate at all. If it still overheats, its low output on the radiator. You may be seeing flow, but it is not enough due to clogged channels.

running with no thermostat is not recommended at all. it will overheat because none of the coolant gets cool in the radiator. since it is always running through the hot engine, it never has a chance to cool. the thermostat keeps certain amounts in the rad to cool it down in between heat cycles of the thermostat.

Hi. I've tried running it w/o the thermostat, but that didnt work. The radiator has been cleaned, but still nothing. As i stated earlier(i think) The transmission is messed up (i think), so mabey thats why its overheating. I'm currently rebuilding it, so we'll see what happens next.

Either the radiator needs replacing or you need to put the fan shroud back on or replace the shroud if sections are missing

Sup, yall. I am MikeVP. I forgot my password, so i made a new account.

Sorry for the 2 year late response . If any of yall who helped me would still like to know the ending of this story, here goes. I had replaced the radiator, and rebuilt the transmission. After that i had no problems. no overheating or loss of power. It ran great. A few months ago it started getting sluggish and was getting horrible gas milage (8-9 MPG). After replacing lots of crap i finally replaced the throttle position sensor, and that helped ALOT, but only raised the milage to about 10-11 mpg. so now a friend said i should replace the Mass airflow sensor. Are there any other sensors i should check/replace???

Also i choose the name bugman114, because i am now deep into restoring old VW beetles. I own three and they are awsome!!! Just so ya kno.