Like the subject says I'm out of ideas guys:

Yes the air dam is in place, I got a 160 stat, edelbrock high flow water pump, a Be-Cool radiator, flex-a-lite 2500cfm fans(grounded) and no kinks in any of the hoses. Yet today and yesterday that SOB starts to boil in the reservoir. I am out of ideas. What am i missing?

 

What about your coolant temp sensor? Is that new or good? Andwhen or do your fans come on? Or do you have them direct wired to an ignition power source?

 

does this happen on the highway or traffic?

 

You're saying it is boiling in the reservoir, what about the radiator cap, I assume it is new right? Also what is the pressure rating on it. What is the coolant temperature while this is happening?

 

This happens on both the highway and in traffic. I've gone through 2 new radiator caps (17). The fans are on all the time and
the temperature reads 240+.

Update: Put a new 160 stat and drilled two holes in it for a little flow and got 220-230 today. Still kinda scary temperatures but I guess thats drivable. Am i missing something?

 

if ur running a 50/50 mixture of coolant, and have all air out of the system i would maybe check for a clog somewhere in the system, most like around the heater core.

you should be running way under 200 degrees.

 

CHECK YOUR TIMING.

next step after that is to pressure test the system.

 

you DID get the right pump for you car didn't you? your car should be running a serpentine belt setup which would use the reverse rotation water pump, if you bought a standard pump it won't cool very well if at all.

 

Definetly got the right water pump. This is a recent problem and the water pump has been working fine for a while now.


Timing check/ Pressure test to come....

 

what is your mixture?

 

check the radiator cap of course.... but i would really check your timing.


my 400 with the be cool would never leave the thermostat setting.

 

It's 50/50. Cap is definetly good. I'm not sure about the timing though.

 

try 100% water with some sorta protector. either use Redline Water Wetter. or that Prestone water pump lubricator stuff. see how much better it will cool. if that works u might just wanan use like a 80\20 water\antifreeze mix.

 

people. his mix is not causing this problem. lol.

:squint: check your timing.

and if its spot on.... get a diff rad cap... and if that doesnt fix it, have the system pressure tested..

its either making too much heat (because of slipped timing) or its not staying pressurized (and the water can boil)

 

its not helping. even if it lowers his temp 5*. thats 5 less degrees he has to worry about while driving around until he gets his problem fixed.

 

*squints at your avatar*
Bedford, Tx???


why does that sound so fimilar? dont i know you from another message board?? o_O

 

I think the question was asked before but I didn't see an answer, but when you changed whatever the last item was in the system, when filling the coolant up, did you let it run with the radiator cap off for about 10 minutes? At least long enough to let all the air get out of the system. Air pockets will sometimes cause an overheating problem. Just a thought.

 

well.. all my problems when i got my car and for the first 2 years were cooling problems... with my old 305 and 350 it was the t-stat. imo the 160s never worked for my car (always got it hotter) so when i put in a 180, it worked fine. (took me 2 years to figure it out)

now with the 406, and being in AZ.. i knew id be screwed.. so i got a griffin radiator BUT put in the 160 t-stat. now... i RARELY see 160 degrees.. and thats either highway/street driving. even at the track it never gets above that 160 line.

 

Im having the exact same problem with my 92. Everything for the cooling system is new. Im dumb founded as to what it could be.

 

gmforums.com?
f-body.com?

 

I'd let it run for a while with no cap and heater on. Bleed the system. You might have some major air pockets and not enough coolant. I had that problem after some engine work, the car heated up FAST!

What was the latest modification you did before this all started. Was it just the cooling sys upgrades?
Are the fans pullers or pushers? Just making sure...
There's got to be air in the rad...

 

probly gmforums..... anyhooo.. hi.

 

I let it run before without the cap for a good amt of time (not exactly sure).

Last modification I did before this happened was a
transmission swap. I dont think it's a problem like this. Everything was fine for at least 2-3 months then all of a sudden it started getting very hot even before the swap. It use to be right at 160 degree mark. Now it's between 220-240.

Btw the fans are pullers. I'm going to go try to run it with the heater on and cap off.

We'll see how she likes it...

 

I think we have a winner....

Let it set for a good 15-20 minutes without a cap and heater on.

Without the cap (heater on) it holds below 160degrees. Put the cap back on and went for a testdrive. Hit 220 only one time and it was because I was doing some very aggressive driving. After I let off it went back down to barely above the 160 mark. That is a definite improvement!!!

Before it would hit 220 and never go below it once it got there. Tomorrow we'll know for sure, suppose to be around 98-101 degrees outside. I hope this does it. Sooooooo tired of dinkin with overheating problems. :lala:

 

reading all the replies and very good usefull info...i have similar problems, going to try out some of your suggestions.
thanks guys

 

I tried everything mentioned above, and also installed a Hypertech fan switch. Still no luck, fans will not turn on or anything even if i turn the AC on it wont do anything.

 

Rad cap fully tightened?

Is the coolant/water ratio about 50-50 or more than 50% water?

If over 50% is coolant, than that could be it, as well as the rad cap being loose. Both have happened to me before.