Did heads/cam about a year ago and didnt have any major overheating problems except on really hot days in traffic would the temp rise to about 220 if i had the a/c on...other than that, with my 160* thermostat, the car ran around 190-200 when driven for a while.
Thats up from around 180-195 before heads/cam (again, these are all approximations).

Anyways, about 6 months ago, a slew of problems left me hunting down codes, trying this and that to clear them out and after slowly knocking them down, one by one, i'm now left with overheating issue. What i've done so far:

-wired fans to stay on high at all times
-have tried different % mixtures of coolant/water and just recently, added a bottle of Royal Purple's "Purple Ice" to ~25% coolant mixture in car
-have bled thoroughly many times
-have checked radiator
-have replaced heater core
-have checked water pump (weep hole and when it was off not too long ago, cleaned it really good
-tuned the car a bit more, to see if that had anything to do with it
-replaced thermostat with another 160*

after all that, car STILL runs hot. I'll drive either highway, city or slow on country roads and it will get to about 190 and stay for a few minutes, then slowly climb up to about 225-235 and wont cool off unless I crack hood while driving, and even then, it barely cools off.

What am i missing or overlooking?

 

-check all the hoses
-check the fan clutch. My buddies Ford ranger was overheating, and it turned out to be the fan clutch.
-and the last resort, pull the heads out and check the headgaskets.

 

oh, forgot to mention the hoses....replaced one of them yesterday (my heater corereturn hose, and the rest have all been taken off and checked, except for the other heater core hose.
I also havent lost any coolant, except when the one cracked.

As for the fan clutch, I'll do a search on it, as I'm not familiar with it at all.

Stupid check me, how would the head gaskets affect coolant temp if they arent blown/cracked/torn ?

thanks

 

Well, that is what I was trying to say. Maybe they are starting to go bad.

 

check your radiator cap, LT1's will run hot if system is not under pressure, mine puzzled me for days, trying to run it with a bad cap.

 

No fan clutch on lt1 cars. Electric fans. Anywho, if you are still running a cat on your car it may be suspect. With a partial pluged or melted cat you are restricting exhaust thus heat. Just a thought i once had an other than chevy have a melted cat ran like sh** and got hot. I didn't have the cash to replace it so gutted it and it fixed the problem.

 

[QUOTE=944v8inDFW]No fan clutch on lt1 cars. Electric fans. [QUOTE]

Thanks for pointing that out, didn't know that

 

wasn't there a recall or "alert" on the radiator caps?
i thought i remembered that one time when i was searching
that could be it

 

Don't know about a recall, But without the cap off i would have sworn there was a head cracked, it kept blowing all the coolant out and boiling, replaced the cap and it cooled down and ran great

 

so he's implying that the radiator cap might lose pressure when system is hot?
If so, wouldnt coolant leak from it or "spray/spew" when pressure is building up?

If thats the case, I've had my car's temp get up to about not too long ago, coolant was almost boiling inside but nothing was coming fro maround the cap.

 

no it will vent into the overflow tank,

 

heck, i guess i could get another one and see what happens

 

www.evanscooling.com

Waterless coolant with better cooling properties than coolant or water and the boiling point is 370*.