When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
So i went down and swapped the thermostat. I noticed the one I had was too long. It was so long the spring would compress when installed.
I replaced with an SLP one. In the pics here you can see the difference in lengths.
However that did not solve my problem. In fact zero coolant went from the radiator to the engine. I drained the coolant 5 minutes after the engine read 235 degrees and climbing. it was room temperature in the radiator (garage temperature)
Since the head change i drove from RALEIGH NC to Florence SC About 3hrs one way. Everything was fine.
However I did buy another high performance water pump (yes I'm throwing parts at it 4 years to get this car where it is and this is the ONLY thing stopping me from racing) I will stick my fingers up the water pump area to see if there is any gasket blocking flow from the head while I have the pump off.
00PooterSS " I am going to use your version of filling this time. When I was down last time I drained the New radiator fluid looked great.
I go back down this Thursday and my first chore is to flush the heater core and make sure its not blocked. Since when I changed the thermostat zero flow went to the radiator. Engine read 239 on HPTuners and the radiator hoses both were cool and so was the water in the radiator. That wast the case before I changed thermostats.
In your method please forgive me for being so clueless. Its not that I just want to make sure I am doing it right. So If you or someone familiar with the process could verify/correct any steps or make sure nothing is left out. I would appreciate it.
I know this is a simple task but after swapping everything except the heater core already and the block testing kit.... and hours of scratching my bald head.... I am 1 step from taking it to a shop which I hate to do. I rather do it myself but when you are defeated, you are defeated. After this round I may have to throw in the towel. I mean new radiator, new condenser, new hose thermostat, 2nd new pump, block tester, total 2 new caps now about to be 4 new caps, The only thing I havent changed is the overflow resivoir, Ill take that up and make sure its not cracked. It steams from it when it first started over heating. I was told that even if it wasnt there, the car shouldnt over heat.
These are the steps with nothing left on the table.
1. leave the cap OFF the radiator (I want sure if it needs to be off or on)
2. make sure some fluid is in the reservoir.
3. unhook the upper radiator hose from the RADIATOR side.
4. crank up the engine, and start filling that upper hose going into the top of the water pump.
5. When the engine is full (fluid at the top of the hose. Connect the hose back to the upper radiator at this point.
6. remove the cardboard/toothpick then tighten the neck snug it to specs.
7. top off the fluid in the radiator.
Air bubbles usually wont completely stop flow into the block, and you already replaced the waterpump and t-stat so there aren't too many other options. Verify the gasket is installed properly, top it off, and squeeze/massage the coolant pipe as the car is idling to help get the coolant to start flowing. Once flowing, it will be easy to bleed properly.
You can do the tooth pick method with out having any hoses off, fill it until it wont take anymore water WITHOUT THE ENGINE RUNNING. It may take a little while for it to be perfectly full so be patient and bring a soda or two with you when you go to fill it.
If you don't prop the thermostat open with the toothpick then pour water/antifreeze into the upper radiator hose until you can't pour anymore fluid in WITHOUT THE ENGINE RUNNING. Then connect the upper hose to the radiator and continue filling the system until it won't take anymore water.
Or do a mixture of both methods like you wrote but do not do it with the engine running. You want it full of water, completely and totally before you turn it on.
Then put your cap on and run the car, if you did it right you shouldn't need to run it with the cap off. See how it does. If it does good let it sit overnight and cool then double check the coolant level in the morning.
However it really sounds like you have another issue here, I've seen blow headgaskets cause a lack of coolant circulation a few times, it's odd and I'm not exactly sure what is going on that causes it, but I have seen a few cars with bad head gaskets not circulate coolant through the system. My best guess is the air that is entering the system is either pumping air into the system and cavitating the water pump, or the air is creating an air pocket and stopping flow (similar to cavitation)
Im glad I asked for the steps. Thursday Ill post the results.
To further explain a little...
Filling it with it running heats up the water and it expands, if you fill it cool you get more water in.
Plus if you take very long the water will start to boil before you get it full. Radiator caps keep the system under pressure, which keeps it from boiling.. no cap equals boiling water. That's why the cap is so important.. pressure. (Boiling point of fluid is higher under pressure, and lower under vacuum)
Lastly if you haven't gotten water into the block and to the back of the thermostat before you start running the motor, it's gonna be a major pain in the *** to get it to take water and act right while filling it. So try to not fill a dry motor while running. A top off is fine while running, but not a complete fill. You want as much in there as absolutely possible first.
Definitely stop letting the engine run that hot,, its not getting you anywhere.. !!
I may get some hate, but I find a bottle of one of the wetting agents added to the coolant helps a lot,,
Redline/Blue Ice pick one they are all the same chemical, they kill the surface tension of the coolant
which helps prevent air bubbles in the system. I've had a engine that would not bleed, pour a bottle in
and poof the bubbles start raging out of the coolant.
FWIW nearly every glycol based building cooling and heating system in the world uses wetting agents,
they increase efficiency , reduce corrosion and help keep pump seals and such in good shape..
Those systems are nothing but a big chilled and heated water system with a radiator..
The water coming out the other piece of hose is good, that means the water went into the block through the thermostat up the lower hose into the radiator and back out the other side of the hose. That will push the air out of the block so you should be good.
What kind of fans do you have? Are they running the right direction? Do both of them come on?
Im back in business took a 30 minute drive it never went over 207 mainly stayed at 198 for a long time... this was in traffic downtown with stoplights.
i think it was air on the engine side. after pooter and some others explained it to me i think i understand.
Also there was nothing wrong with the long thermostat... the spring push back is by design. (im learning)😁
the engine side took a little over 1.5 gallons filling it from the top.
before following all of the instructions my car would get super hot in 2 to 3 minutes just idling.
my biggest mistakes....
1. throwing parts at it
2. not turning on the heat.
3. filling it while running.
4. not having water in the overflow b4 filling.
now to start another thread on getting my speedo to work.
Real quick question after finally grasping a little better understanding of the cooling system.
I have recently switched to an electric water pump. Just because..... I was fine with the mechanical.....
All of these problems with air...
If you have two holes drilled in the thermostat.. wouldn't that be the easiest fix to rid air bubbles. The air cant stay trapped if there is an escape.... Am I overthinking this? I had other issues as well that got sorted in this thread but the ultimate I think may have been the air in the system.
If I am wrong please come in and correct me but to eliminate that as a possible culprit couldn't we just drill two holes and never look back?
I am only mentioning this in case it can help someone else... but I would like some of the seasoned guys to confirm.
I know many have been doing this all along, its nothing new at all. I just wish I had tried that before. Its the first thing I did with the electrical pump.
Drilling holes in the thermostat is a horrible idea, the thermostat won't be able to control water flow and keep it cooled/heated
Thermostats are a little more complex than most think.
They stay closed when the motor is cold to help it heat up.
They open when the motor warms up but they only open a certain amount, if they open too much or something has happened to creates excess water flow (like drilling holes) the water speed will be too high and pass through the radiator too fast not giving it enough time to cool back down before re entering the engine.
I learned this the hard way when I was 17, it took me years before I knew what happened.. I took my thermostat out of my car in January and it was in the 20's outside, the car immediately overheated and stayed overheating with no thermostat in it..
That's why I recommended wedging the thermostat just a tad open with a piece of tooth pick, and you have to lightly open the thermostat when you do this or you can wedge it to the side and lock it open, you'll know if you do that, it'll be open and cocked sideways, just have to move the center pin back to the guide in the middle. If you wedge the toothpick piece in there, when the thermostat opens it will eject the tooth pick and allow the thermostat to close all the way when the engine cools down.
Once you run a car and the coolant circulates (thermostat has opened and allowed flow) the air should move to the top and once it cools down you should be able to fill it and be done. There's no other way for air to continue to enter the system unless you have a blow head gasket introducing air or some sort of funky leak that allows air in, but if you did you should have a coolant leak.
Last edited by 00pooterSS; 07-16-2018 at 04:34 PM.
You could drill a very small hole (like 1/8 inch) in the themostat just for the air bubbles/pockets and to help the bleeding of the system. On the Corvette side I have heard when they went to an electric pump a small hole in the thermostat helped with the bleeding of the system. I agree with guy above the thermostat needs to work properly large holes are not going to help with the cooling. A small hole will not change cooling things but may help with your bleeding process since yours seems to be more of a problem. On mine I just take the plews suction gun to small overflow tank hose and just pull the air through that way until I start sucking nothing but water. That gets is 95% of the way there with a top off after a drive for a few miles.
I got me one of those vacuum test and fill kits from the snap on guy. It sucks the system into a vacuum then you fill using pick up tube and 5 gallon bucket with your coolant mix. It works really good.
I have a snap on account and I get a tool allowance from my employer so thats why I got the snap on version. But you can get them from other places and they aren't so expensive. I highly recommend them. Saves time and virtually eliminates the chance for vapor locking.
06-18-2018, 03:27 PM
