My car has been overheating constantly and cannot figure out what else to do for it. Its fresh rebuilt 2002 6.0 with big cam , turbocharged , 4l60e with a stall in a 70 chevelle.

Over the course of 30 minutes of driving it will creep up to 240 degrees.

Thermostat is opening, fans are on high as soon as it reaches 190 , 50/50 antifreeze mix, aluminum dual 1" tube radiator(have thought about maybe flushing it out),
and ive tried to bleed air out with nothing but coolant coming out.

I even got the nose of the car 4 feet in air to help with any trapped air.

I verified correct wp rotation and the water pump doesn't even have 40,000 miles on it.

Im ready to pull my hair out trying to fix this issue.

Anybody have any ideas on what to check next? The only other thing I can hink of is to get a temp gun and check the radiator to see if its even getting that hot.

 

No leaks or loss of coolant?

 

Zero leaks and coolant level seems consistant.

 

I would try taking the thermostat out and see if it runs cooler. How did you test it?

 

Ok i guess ill remove the thermostat and see what it does. I wouldnt think its the thermo stat since both the radiator end tanks get very hot.

 

Its a quick way to troubleshoot for free, could be partially opening. Not saying that's the issue but I like to troubleshoot rather than shotgun parts.

 

I agree i dont like throwing new parts at problems Either. I have a bottle of radiator flush at the house so i will go ahead and give the system a good flush and pull the thermostat out and see what happens after work.

 

Sounds good, post the result and we will go from there

 

you can always check both hoses on the radiator, they should both be hot if running correctly. Just for sh*ts and giggles,are you running an intercooler?

 

Flushing isnt going to do anything. Unless you have a rag stuck in there, there's not much that can clog a rather new set up.

Almost ALL overheating issues for hybrid set ups like yours is the FAN SHROUD. Or when aftermarket radiators are used, a lot of times different shrouds are used or the factory shroud doesn't fit right. If the shroud is not factory and/or installed to the back of the radiator exactly like the factory does it.....you will always have overheating problems. The air that the fans pull through the radiator must sealed so its pulled through the front and then ALL of that air gets rammed against the entire surface of the front of the radiator. If any of that air is lost through the edges.......no way you'll stay cool. That goes for highway driving to....the ram air does 100% of the cooling while cursing and the fans should be off. If that air cannot go up and ALL of it goes directly through the front surface of the radiator it WILL NOT cool the coolant efficiently.

Can you take pictures of the way the radiator and fan shroud are set up....?

On that car you'll need a fabbed aluminum sheet metal shroud that fits perfectly.....or go back to a factory stock radiator and factory shroud.....which is all you need if the system is operating properly.

But yes......always use a laser temp gauge. Make sure you're actually running those temps. I've helped a handful of people who were chasing overheating problems and all I did after they went nuts for weeks trying to figure out what was wrong.....is I hit the head with a laser temp gauge. Their temp gauge was just reading wrong. They were never hot.i can tell you this. At 240*F...if it truly is 240*F.......if you pull over and put your hand on the plastic style LSx intakes.....you won't be able to keep your hand on it without burning your hand. At 185-200*F......you can keep your hand there......

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I am running some radiator flush and just water now and still hit 235 today on my way to work with no thermostat. This is at 30 minutes of driving.

Ill snap some pics in a minute of the radiator setup. The 94 Camaro lt1 fans and shroud are secure and flat on the radiator and in the the tune im running them on high on the highway too just too help.

I am running a big intercooler up front as well with a 2 to 3 inch gap between radiator and intercooler.

The radiator does have a little surface film/sludge in it from 8 years of use.And when flushing out the systm of coolant for the flush treatment, a bunch of rusty water came out, so if anything im getting debri out of the cooling sytem.

This is a year old temp sensor and am looking at temp in log and not the physical guage.

Now will the hand on hot intake be the same for a truck intake? I will put my hand on it when I get home.

Will post pics of setup in a few.

 

Heres a few picks of the radiator fan setup. the driverside has about a 3/8 gap on the one side.

 

Forget the flush. Flushing is only used when you have known contaminants that got into your coolant system.

Running the fans while on the highway does nothing. The ram air alone does better than the fans can ever dream of doing. So you are most likely slowing the ram air down while cursing on the highway.

If there isn't a divider wall between the IC and radiator.....you might have found your problem. You need to put a piece of sheet metal about 1-2 inches behind the IC and direct the hot air downward.
It's just like when people lay tranny coolers up against their condenser or radiator......they just make a hot spot in that surface area and reduce the cooling efficiency of the radiator.
Your hot air coming off the IC is slamming right into the radiator.
Put a divider wall in there.......

That's cool......but as long as the coolant is moving through the system, it's going to cool just fine. Getting some nasty **** out of there isn't going to change things for you. But obviously it can't hurt.
Your issue is much bigger than some rusty water.....

Use a laser temp gauge......to be 100% sure. Hit it at the head right next to the temp sensor.
This way you can also know what your gauge is really reading, regardless of the number showing on the gauge.

Yes. As long as its plastic. L76....?

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It will surprise you how much just a little gap in the shroud affects the cooling ability. Maybe use some black duct tape....temporarily.....just to see if covering all the gaps in the shroud all the way around will help.

But you need a divider inbetween the IC and a radiator. That's not good.

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Alright..i noticed that the water in radiator isnt boiling at 225 and the intake barely feels warm .
My guage hasnt been working on dash and wonder if there is an issue with the sensor.
On the scan it Looks like it reads correct at ambiant temp then progressivly goes up

 

The sensors in our cars aren't that great. The gauge readings are sometimes close to true temps, but most of our cars are way off.

I used a laser temp gauge to see what my true temps were at the head next to the sensor when my engine was at normal operating temp. The gauge reads 155*F.......true temp is 185-190*F.
S when I'm out driving I know when it reads 155.... It's perfect at 185-190. Then when I turn the A/C on and it gets hotter in stop and go traffic.....my gauge reads 210.......true temp is 215.

So I know what temps I'm running on my gauge.

You should do the same thing.

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Yikes, that's way off lol. I will be ge getting a laser temp gun then. I started going through the harness to find the ect wire ends and the ground for it was just grounded to the frame when it should've been going to the pcm pin for an isolated ground. My mistake.

Maybe this was the culprit?!?

Of course my laptop died as soon as I got in my drive into work, so don't know yet if it fixed the false readings. I know electrical noise can throw stuff like this off so am hoping its the cause.

Will update after my drive home today from work.

 

was it sensor or something more with this one?