Question on adding coolant to radiator

-
72Plymouth

72Plymouth

Well-Known Member
Joined
Jun 5, 2010
Messages
764
Reaction score
35
Location
Vista, CA
The car is cold and hasn't been on for a week. I pulled the cap off and I saw that the coolant wasn't over the metal cooling passages. I added almost a full jug of coolant and it still didn't even submerge those passages inside.

I checked the cap a few months ago and there was some coolant inside the radiator (car was warm). I know that a little overflowed out the other day from the overflow tube but didn't think it could use that much up.

Should I keep filling it until the coolant is just below the bottom part of the cap?
Just wanted to make sure that I do not over fill it because it's cold and I haven't started it in a bit.

It has a 318
 
Best mix is 50/50 water and antifreeze. Get yourself an aftermarket rad overflow bottle to connect to the overflow tube. Check for leaks or wet spots. Coolant expands when hot and will go into the bottle and will be drawn back into the rad when the engine cools down.
 
Yup I added the premixed 50/50 jug. Is it better to run the engine for a bit to normal temp then check the radiator after it cools for a bit? Just didn't want to pull the cap when its hot and have all the coolant shoot out.

But would that be the best way to tell how much coolant is in there or should it always be filled with coolant just below the cap area even when its cold?

Also the cap would need to be changed if I get a tank right (someone said on another thread)?
 
72Plymouth said:
Yup I added the premixed 50/50 jug. Is it better to run the engine for a bit to normal temp then check the radiator after it cools for a bit? Just didn't want to pull the cap when its hot and have all the coolant shoot out.

But would that be the best way to tell how much coolant is in there or should it always be filled with coolant just below the cap area even when its cold?

Also the cap would need to be changed if I get a tank right?
Click to expand...

Most caps now are designed for an overflow bottle. Your right, it's best to remove the cap when the engine has cooled down. You don't want a steam or hot antifreeze burn.
The coolant should cover the rad tubes when cold.
 
You can fill it cold, and all my cars like to run about an inch or so over the cooling tubes. If I overfill them, they just fill the recovery bottle up anyway. Keep an eye on it after everytime you drive it for the next couple times. If it is continually using a quart or more when running about an inch or so above the tubes, a problem exists somewhere and should be addressed. I would hook up a recovery bottle first off and check that while the car is up to temp. Hows the temp guage reading?? Don't pull the cap while the car is up to temp, EVER!!! You can, however run the car without the cap and check the flow of the water pump when it reaches temp and the thermostat opens. You can also check the coolant for bubbles (big bubbles) indicating air in the water being introduced by a blown head gasket. A gallon low on coolant is a lot, and should be monitored closely for the next few trips. Good luck with your project, Geof
 
cosgig said:
You can fill it cold, and all my cars like to run about an inch or so over the cooling tubes. If I overfill them, they just fill the recovery bottle up anyway. Keep an eye on it after everytime you drive it for the next couple times. If it is continually using a quart or more when running about an inch or so above the tubes, a problem exists somewhere and should be addressed. I would hook up a recovery bottle first off and check that while the car is up to temp. Hows the temp guage reading?? Don't pull the cap while the car is up to temp, EVER!!! You can, however run the car without the cap and check the flow of the water pump when it reaches temp and the thermostat opens. You can also check the coolant for bubbles (big bubbles) indicating air in the water being introduced by a blown head gasket. A gallon low on coolant is a lot, and should be monitored closely for the next few trips. Good luck with your project, Geof
Click to expand...

I don't have a recovery bottle, just a tube that dumps it.

Last time I was letting the car warm up for like 5 minutes or so and it got to temp. After that, the gauge read almost all the way to the hottest and coolant/steam was coming out of the tube. Then it cooled once I started driving it.
 
I would hook up a recovery bottle asap and eliminate the car dumping fluid on the ground. A recovery bottle is as easy as getting a pop bottle with a cap, drilling a hole in the cap the size of your overflow hose and stuffing the hose through the hole. Then just wedge the bottle down along the side of the radiator where the overflow tube routes. Make sure the tube sits on the bottom of the bottle so it can syphon fluid out of the bottle. Now you have a recovery bottle to work with and monitor. You can buy a more permanent system as you go, but this setup will allow you to monitor the fluid of your car.

The car should operate at or near 1/4 of the way up on the guage. If there is a great fluctuation between normal operating temp and sitting at idle then you need to review what your system is doing. What temp is your thermostat? Is it a high flow thermostat?? Have you flushed out your radiator? How is your water pump flowing? Do you have a shroud? Are you running a flex fan or an OE style clutch fan?? Or maybe an electric fan?? All of these things need to be addressed and in order to eliminate each as a possible cause of your overheating and water loss problem. Report back with any additional information you can about your system and we'll go through them one by one and try to get that baby cooled down!!! Geof
 
cosgig said:
I would hook up a recovery bottle asap and eliminate the car dumping fluid on the ground. A recovery bottle is as easy as getting a pop bottle with a cap, drilling a hole in the cap the size of your overflow hose and stuffing the hose through the hole. Then just wedge the bottle down along the side of the radiator where the overflow tube routes. Make sure the tube sits on the bottom of the bottle so it can syphon fluid out of the bottle. Now you have a recovery bottle to work with and monitor. You can buy a more permanent system as you go, but this setup will allow you to monitor the fluid of your car.

The car should operate at or near 1/4 of the way up on the guage. If there is a great fluctuation between normal operating temp and sitting at idle then you need to review what your system is doing. What temp is your thermostat? Is it a high flow thermostat?? Have you flushed out your radiator? How is your water pump flowing? Do you have a shroud? Are you running a flex fan or an OE style clutch fan?? Or maybe an electric fan?? All of these things need to be addressed and in order to eliminate each as a possible cause of your overheating and water loss problem. Report back with any additional information you can about your system and we'll go through them one by one and try to get that baby cooled down!!! Geof
Click to expand...

It is all stock, so yes it has the shroud and clutch fan. Looks like a newer water pump. Haven't flushed it.

Ok so all together I added about a jug and a half of coolant and it runs a lot cooler now. The temp gauge barely gets above the coolest side. About 1/5 of the way up. It was just really low. Last time when the car was idling and warming up, it started to overheat. I will need to keep an eye on it to make sure it isn't loosing any coolant.

Thanks again
 
You could also try to find a radiator cap that has a thermostat gauge built into the cap itself. I believe Mr. Gasket makes these caps.I have this style cap on my Duster and it is very helpful not only to monitor your coolant temp, but also to let you know when it is safe to open up the cap.you NEVER want to remove a radiator cap that has been under pressure and is hot. You can get very badly burned.
 
I bought an aftermarket overflow bottle from Autozone for like $7 and it works great.But the hoses that come with it suck.I bought different hoses for it.
 
check that your cap is good , mine was dumping fluid and running a bit hot , tested the cap , it was only good for 10lbs pressure . Replaced with good cap and it has not dumped any fluid , runs cool.
 
You must log in or register to reply here.
-

Back
Top