94CovertCorvette

Well Summer finally hit Austin here and I was running my 94 lt1 vette from San Marcos to Austin (about 35 Miles) avg speed was around 70mph no traffic jams and the ac was on cause it was 101 and low wind. The ac was on and my temps climbed to 255-257 before I reached Austin.
I turned the AC off fearing a engine melt down and the temps dropped to 247 ish.
I looked a the radiator cap and it was rusty and was most likely the original cap, so I replaced it, Had a local shop flush the radiator of the rusty looking fluid, and put in a Hyper Tec T-160 and drove it again. It helped keep the temps around 230max. This weeks weather temps were low 90's
Then I drove it yesterday and the weather reach 97 and the vette climbed to 240 again and When I shut it down the Drive way a Bubbling sound came from the surge tank and I could see bubbles coming from the bottom of the neck below the rad cap.
So am I missing something?
Do I need to replace the Radiator, Hi flow water pump (Meziere high flow electric water pump comes to mind), or maybe just the surge tank is not holding the pressure?
Thanks for any ideas on how to help keep my vette cool.

Cozmo

Bummer! What part of Austin are you in? I am southwest. If you cant figure it out, let me know. I can introduce you to a local shop that has done good work on my car.

94CovertCorvette

North Austin, Round Rock area close to Dell.
What does your vette run temp wise here in austin?

tempest

might want to clean out the crap that's accumulated on your radiator. you can do it without removing the rad, but just the top shroud.

check to see if your fans are working too. you can just let it idle for a few minutes until the fans turn on, at which point the temps better drop.

incidentally, a 160 T-stat does not help with the high temps, but just delays the time it gets there (unless you turn the fans on early via Hypertech or a manual switch).

Cozmo

The coolant temp has been running around 205 lately. You definately have a problem. Your car is way too hot. Best fix it before you damage something or it strands you. Austin Corvette is on N. Lamar, just south of Braker. Gary Kropat there is a member of the local vette club, he just changed the plugs and wires on my car yesterday. He also installed my magnaflows. He does good work. Try can call him at 339-8388.

Larry

94CovertCorvette

Tempest,
Ill look at the cleaning it out this weekend and get and stuff out of there. I did check the fans and they are both on.
Any other Ideas?

CF6873

Definetly clean out the fins on the rad and the AC condensor. I just pulled mine out this week and I could barely see through the fins on both. They were packed full of sand and leaves and all kinds of stuff. I spent almost 2 hours with a blow gun with 100 psi until I got it all out. I have not yet driven it but I will tomorrow and I'm betting it will run alot cooler. Craig

Jet-Jock

You can use a piece of 3/4 inch PVC pipe and cut a long angle on it and tape the other end, couple feet long, to your vacuum hose. The PVC pipe is just small enough to go into the opening on the passenger side. The angle cut allows the pipe to go in yet make a flat path across the front of the radiator. Be extremely careful not to damage the fins. Take your time. Someone holding a flash light helps too.

Strick

I think you've heard it all. Clean out the fins of the radiator, flush the entire system and refill with 50/50 mix of coolant and distilled water, check for leaks, especially under the water pump which would indicate a soon to be failure of the pump, yes, an upgrade to the Meziere electric water pump would be nice and make sure you are using the correct coolant (most use the green stuff) and never mix the two kinds. If this doesn't fix you up, have the mechanic hook up a Tech II scan tool and see what the temps really are.

Oh, I forgot, make sure ALL the air is out of your system.

Muffin

Agree with all the above for sure. I used "Water Wetter" with some good results and am suprised that someone hasn't mentioned it. I would do the cleaning and flushing before I considered any of the additives.

tempest

one more thing... check the line going from the surge tank to the clear overflow tank to see if it's clogged. if the pressure builds enough it should dump the water straight to the overflow, and not bubble at the cap.

bamabcs

I just dealt with this problem in my 94. had the same ideas as you, hi flow, cleaning, etc... I even flushed the system. I decided to go with a new radiator... and it worked!!
Im in south AL and have similar temps. I was running up to 240 with AC on. Now Im running 193, 205 idle with AC. I went back with a stock radiator $200 from a local shop, I think corvette fever had them for about that. It keeps my 383 stroker cool now.
Be sure and check, replace and/or clean all hoses if you do the work, don't want to gunk up that new radiator. My AC is even cooler now.

Southern Comfort

Snake Oil.....JMHO

didn't work for me