You need to be sure all the air is completely out of the system...It may take a few times of letting it out to get it right..its not always a 1 shot deal Good Luck!

 

It sound like air in the system and like Stump said it can take a few tries to get it bleed out. Also be careful opening the bleeder screws because they are about 10 bucks a piece and only available at the dealer.

 

Where are the bleeder screws located at? 1 other think that I noticed is the antifreeze that they gave me to put in it was clumpy. I noticed it after I was about done filling it. I was gonna drain it and put new in but the owner wanted that antifreeze in it. I thought they mite just heat up and melt but I just found out that the antifreeze is very old. (its not my car).

 

You need to flush the goop(clumpy) out Immediately! No wonder your haveing overheating issues!

You should have told us that on your first post! You need to flush it a minimum of 2 to 3 times to be sure you get it all out!/ besure to turn on the heater so as to throughly flush the heater core !

Then you need to use the proper mix of water vs (new)antifreeze for proper cooling./performance.

 

Yup gonna flush it in the morning and go buy some good antifreeze for it. I asked them where they got the antifreeze a couple hours ago and they told me they found it in a shed and they had no idea how old it was. Not cool I told them. It was mixed right and I didn't notice the clumps till it was about full. I figured that mite be the only one but after hearing how old this crap is its kinda obvious. Thanks for the help.

How do you recommend to bleed the system?

 

Never-mind I got it. Thanks.

2000 Chevrolet Monte Carlo V6-3.4L VIN E
Coolant: Service and Repair
Ethylene glycol/water fill ratios have been established to ensure a minimum of 50 percent ethylene glycol. Ensure that all the engine block drains and air bleeds are utilized. The cooling system capacity for the 3.41L is 10.4 liters (10.9 quarts). The cooling system capacity for the 3.81L is 9.6 liters (10.1 quarts). The quantities listed in the filling procedure include the additional quantity to displace the air remaining in the cooling system after a static refill. Unless the cooling system is completely drained, residual coolant reduces the amount of coolant required to fill the system. Always check the freeze point protection after filling a cooling system. Using the correct fill ratio and the following procedures will ensure a minimum concentration of 50 percent ethylene glycol. Every five years or 240,000 km, (150,000 miles), whichever occurs first, the cooling system should be drained and filled using the following procedure.
Caution: As long as there is pressure in the cooling system, the temperature can be considerably higher than the boiling temperature of the solution in the radiator without causing the solution to boil. Removal of the pressure cap while the engine is hot and pressure is high will cause the solution to boil instantaneously -possibly with explosive force - spewing the solution over the engine, fenders and the person removing the cap.
Notice: When adding coolant, it is important that you use GM Goodwrench DEX-COOL(R) or HAVOLINE(R) DEX-COOL(R) coolant. If Coolant other than DEX-COOL(R) or HAVOLINE(R) DEX-COOL(R) is added to the system the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.
Draining Procedure
Important: This procedure significantly increases the amount of used coolant and diluted hazardous waste.
1.Park the vehicle on a level surface. 2.Remove and clean coolant recovery reservoir. 3.Remove the radiator cap when the engine is cool: 3.1.Slowly rotating the cap counterclockwise to the detent. Do not press down while rotating pressure cap. 3.2.Wait until any residual pressure (indicated by a hissing sound) is relieved. 3.3.After all hissing stops, continue to rotate the cap counterclockwise.
Filling Procedure
Important: Store the used coolant in a used coolant holding tank. Submit the used coolant for recycling.
4.Place a drain pan under vehicle to collect all the drained coolant.
Important: For procedures requiring the cooling system to be partially drained, opening the radiator drain valve should provide sufficient draining and no further actions should be necessary.
5.Open the radiator drain valve located at the bottom of the radiator tank.
6.3.4L - Open the air bleed vent (1) on the thermostat housing. The air bleed vent should be opened two to three turns.
7.3.4L - Open the air bleed vent (1) on the thermostat bypass pipe. The air bleed vent should be opened two to three turns.
8.3.8L - Open the air bleed vent (1) on the thermostat housing. The air bleed vent should be opened two to three turns.
9.3.4L - Remove the engine block coolant drain plug from the engine left side.
10.3.4L - Remove the engine block coolant drain plug from the engine right side.
11.3.8L - Remove both block drains (knock sensors).
Important: Dispose of used coolant in a proper fashion. Never pour used coolant down the drain. Ethylene glycol antifreeze is a very toxic chemical; disposing of it into the sewer system or ground water is both illegal and ecologically unsound!
12.Allow the coolant to drain completely.
Notice: DO NOT use cooling system seal tabs (or similar compounds) unless otherwise instructed. The use of cooling system seal tabs (or similar compounds) may restrict coolant flow through the passages of the cooling system or the engine components. Restricted coolant flow may cause engine overheating and/or damage to the cooling system or the engine components/assembly.
1.Close the radiator drain valve.
2.3.8L - Install both block drains (knock sensors).
3.3.4L - Install the engine block coolant drain plug to the engine right side.
4.3.4L - Install the engine block coolant drain plug to the engine left side. 5.Remove the coolant recovery reservoir and empty. Flush the reservoir with clean water. Install the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement.
Important: -When filling the cooling system, add GM approved Ethylene Glycol Coolant DEX-COOL GM P/N 12346290.-If the cooling system is being refilled ONLY (no flush), a 50 percent ethylene glycol and 50 percent clean drinkable water mixture should be used to fill the system. Fill the system until the level of the 50/50 mixture has reached the base of the radiator neck. Wait two minutes. Check the level of the coolant mixture. Add a 50/50 ethylene glycol/water mixture as necessary to restore the coolant mixture level to the base of the radiator neck. 6.Slowly fill the cooling system through the radiator neck using the following procedure: 6.1.If the coolant system has been flushed first add 100 percent ethylene glycol:-3.4L - 5.2 L (5.45 qt.)-3.8L - 4.8 L (5.05 qt.) 6.2.Slowly add clean drinkable water to the system until the level of the coolant mixture has reached the base of the radiator neck. 6.3.Wait for two minutes. Check the level of the coolant mixture. Add clean drinkable water if necessary to restore the coolant mixture level to the base of the radiator neck. 7.Install the radiator cap making certain the arrows line up with the overflow tube.
8.3.8L - Close the air bleed valve (1) on the thermostat housing.
Important: DO NOT over-torque the air bleed valve. The air bleed valve is made out of brass.
9.3.4L - Close the air bleed valve (1) on the thermostat bypass pipe.
10.3.4L - Close the air bleed valve (1) on the thermostat housing. 11.Fill the coolant recovery reservoir to the COLD mark with of a 50/50 mixture of ethylene glycol and clean drinkable water.
Notice: The Low Coolant warning/indicator lamp may come on after this procedure. If after operating the vehicle so that the engine heats up and cools down three times, the Low Coolant warning/indicator lamp does not go out, or fails to come on at the ignition check, and the coolant is above the full cold mark in the reservoir, refer to Low Coolant Warning/indicator Lamp in Instrument Panel, Gauges and Warning Indicators. If at any time the Temperature warning/indicator lamp comes on, immediate action is required. Turn OFF the engine and allow the vehicle to cool. Do not remove the coolant recovery reservoir cap at this time.
12.Inspect the freeze protection of the engine coolant after the engine heats up and cools down three times using a refractometer or a thermohydrometer to ensure proper freeze -37° C (-34° F) protection. Obtain the coolant mixture for the inspection from the base of the radiator neck, NOT from the coolant recovery reservoir.

 

Ok this car is getting annoying lol. I flushed it 4 times and put new antifreeze and bled it real good and it ran fine no overheating drove it of 20 miles or so and it was fine. Heat was nice and worm car ran at right around 200 deg. BUT this morning it was started and run for 1 mile and it overheated. The cap on the radiator was caked in oil sludge and I cleaned it off real good. Could the cap be causing this? It did have that intake gasket go out over a year ago and put oil in the cooling system. When they had that fixed the system was supposed to be flushed out and cleaned. It has a new thermostat new antifreeze and has been flush and bled.

 

im thinking you have a head gasket issue. when the intake gasket was replaced they should of done the head gaskets as well. or you may have a block somewhere from the "clumpy" sludge u dumped into it for new coolant. im thinking for how many times it over heated now it needs new gaskets anyway and probably the heads machined flat do to all of the overheating that was there for so many times....

 

It does sound like a headgasket issue at this point. Although a new radiator cap is a $10 attempt.

 

I agree with the head gasket. From what it looks like the people that did the intake gasket did not do a very good job so I am about positive that they were not changed. The owners of the car don't like spending money (as you can tell by the antifreeze they had me put in it) which in my opinion always causes problems.