Overheating.

Something is obviously failing if it ran good before. How are the hoses? Soft radiator hoses will collapse under pressure, a tiny leak in the cooling system can cause the coolant to steam out of the overflow tank, or maybe the coolant isn't flowing correctly.

6Stang7 said:

My stang is still over heating (steam shoots out of the radiator over flow when I turn the engine off after driving it) and I can figure out what it is. It always got a little high, but I figured it was cause I had no fan shroud. After pulling the intake off, getting it cleaned, then putting it back on I now have it getting even hotter. I tired retarding the timing, riching the air/fuel, and pulling the thermostat, but none of it has done anything!!!! What else could be going on here? I never did this before I took her off the road 5 months ago?

-Shaun

Click to expand...

Well retarding the timing and pulling the thermostat out can both CAUSE overheating, so chances are those didn't help matters. Did you read my last reply to your other overheating post? (i posted it last night) Did you check all of the things listed?
Also, if you overtighten the intake, it can sometimes act like a wedge and try to drive the heads off the block, which can make a leaking headgasket worse. Are you sure the headgaskets arent on backwards?
Read the other post from last night, it might help....

Dave-

EDIT: I just noticed it was gbarbur's thread, not yours... but I remember seeing your name in it, so you should remember which one I mean. Check it out....

1. You might not want to hear it, But Leaky headgasket.


Or you have air trapped inside.

Purging coolant after run is air pressure locked in form compression leakage.

Fill rad 3/4 full of coolant,leave cap off, run motor to operating temp.
you should see coolant flow at steady speed while at idle.
SLOWLY fill while running till about 7/8 full, place good rad cap on and drive.

If it purges after that, Go to back to 1.

PB

Yes.
It's the beginning of a section leak near the coolant jackets.
the compression stroke of the leaking cyl will pump air into the
cooling system like a Tire pump.

make sure to remove ALL the plugs for your test.

PB

Hmmmmmm.... well a bad cap could lead it to o-heat more easily. The pressure provided by the cap also raises the boiling point, so the cap could drop it *some* but I wouldnt think more than 10-15 degrees.
Hot air being pulled back around the radiator could also make things worse, but I would think that the heat dissipation without the hood would MORE than make up for this...
Blocking off the exhaust crossover below the carb, will hurt cold start-up, but should help the o-heating problem.
Do you still have the stock steel 4 or 5 blade fan on it? A flex-i-lite or an electric might be a good upgrade.
In addition to a compression test, most shops can use a "block tester" where they test the coolant / radiator for the pressence of combustion gasses. A sign of a blown HG. Takes about 10 min, probably charge ya $20 if at all.
Is the fan belt the right tension? If its loose than the water pump won't turn like it should.
If you have any big gaps in the core-support next to / above / below the radiator, you might want to block them off (cardboard for a temp test ) to make sure that ALL the air is going through the radiator and not around it... this will not be such a problem on the highway, but will be more noticeable in town, where the volume of air is lower (slower) so it is more crutial.
Also try to feel the radiator just as the thermostat opens, (and it starts to get warm) and feel for cold spots. This will indicate that there is a lack of flow in that area of the radiator. If this is the case, rebuild it or get a new one.
Also check to see that your shroud fits well, no big gaps, the fan isnt way up inside it, or hanging out an inch behind it, etc...
The hole in the thermostat that you drilled is always a good idea. The *slow* trickeling in is the time it takes the air to escape out that hole. If you hadn't drilled the hole, that air would be trapped completely. (until the stat opens)
It sounds like your on the right track....
Check your coolant mix is 50/50 to 60/40 h20/coolant. Too much coolant can HURT the cooling ability of the system. (too little and you have a cracked block in January)
You could run some "Redline: Water Wetter", Summit carries it, and it helps about 5-10 degrees.
If all else fails you could try a good 160 stat, may-be the other one you had was wasted.... you could check it in a pan with a thermometer and watch for temp and smoothe opperation.
Hope some of this helps.
Dave

Maybe you've already heard this, but you might try pressure testing the cooling system. My machine shop guy let me borrow his pressure tester to rule out a leaking head gasket or any other source of leaks. I pressurized the system to 20 PSI and it held for several hours. I was told that if the pressure bled off fairly quickly and I could not find the leak outside the engine (hoses, waterpump, etc.), I would probably find coolant in the cylinders or in the oil pan. (head gasket leak)
Fortunately, I think my problem was air trapped in the system after my recent engine rebuild. I replaced my thermostat, and drilled an 1/8 inch hole in the outer rim of the stat to help purge air trapped in the system. I positioned the hole at the top of thermostat housing. (12 O'clock) After running the engine with the radiator cap off for 20 minutes, I had no further problems with too much pressure building up at relatively low water temps.
If you had your intake off recently, you may have some air still trapped inside the engine. Before I got rid of the air in my engine, I would have coolant coming out the overflow at around 190*.
Hopefully your problem is something similar.

6Stang7 said:

I did have a coolent leak from the thermostat housing, but I tightend the bolts and got it to stop.
-Shaun

Click to expand...

My Camaro had a similar situation with the steaming out of the recovery tank. We'd fill it up with water and it would drive okay for a few miles then steam again. It caused the top hose to collapse. After opening the radiator cap (with a thick towel) the hose would pop back to it's original shape. A new hose didn't help either. It turned out to be a really small leak in the bottom tank that wasn't evident initially but showed itself a few days later with a small drip at the seams. Short of buying anything more, I guess a pressure test of your cooling system might be a good idea as others have mentioned, the pressure in the system is very important to keep coolant from boiling. I would use just water to test and refill with 50/50 after you fix it. Water is actually the best coolant for just plain cooling. The anti-freeze is just what it implies, anti-freeze. I use bottled distilled water, less contaminents and not very expensive. Good luck.

ddonaca351 said:

Well retarding the timing and pulling the thermostat out can both CAUSE overheating, so chances are those didn't help matters. Did you read my last reply to your other overheating post? (i posted it last night) Did you check all of the things listed?
Also, if you overtighten the intake, it can sometimes act like a wedge and try to drive the heads off the block, which can make a leaking headgasket worse. Are you sure the headgaskets arent on backwards?
Read the other post from last night, it might help....

Dave-

EDIT: I just noticed it was gbarbur's thread, not yours... but I remember seeing your name in it, so you should remember which one I mean. Check it out....

Click to expand...

Retarding the timing should make the engine run slightly cooler. (there is less combustion time / less heat)

I guess I don't understand how pulling the thermostat CAUSES overheating...

Speed_Demon1965 said:

Retarding the timing should make the engine run slightly cooler. (there is less combustion time / less heat)

I guess I don't understand how pulling the thermostat CAUSES overheating...

Click to expand...

Without a thermostat in place to control the flow of coolant,
It is possable for the temp to rise above the recommended level.

Too much coolant flowing will not allow it to disapate the heat from the rad.
before it goes back in to the engine.

PB

Did you ever change the head gaskets Shaun?

If so did you make sure that the gaskets pointed forward blocking off the front cooling passage?

If not well this could be a problem other than your water pump/radiator.

Why don't you open it up using a portable torch and use a dip stick to run it through the cooling veins. Weld back together with soder.

If you'd prefer not to open it use muriac acid found in pool supplies pour some in let sit then rinse out this of course off the car.

have you checked your theromstat functionality?? drop it in a pan of boiling water with a thermometer....does it open at the correct setting??

go to a lower cap pressure.....