radiator problem

[malexander44]

Hey guys...

Got a question for ya. I just replaced the water pump and thermostat on my 63 350 and now my radiator is pushing water out of the overflow valve when it gets up to running temp. Any suggestions on what it could be? I just did (10 minutes ago) a flush to the system, with the same effect.

What do you all think?

Mark

[joe231]

check to see if you have the correct pressure radiator cap.....
also need to make sure it functions properly, or just get a new one, they are inexpensive

[malexander44]

I'll just buy a new one. What or where can I find the correct pressure cap that I need? Also, does anyone run an overflow catch tank or does it just drain to the ground? Mine just drains to the ground now. What are your suggestions?

Thanks
Mark

[malexander44]

I know that the autoparts store will carry the cap, what I meant to say was... is there something on the radiator that will tell me the pressure cap that I need?

Mark

[joe231]

these trucks didn't come with over-flow bottles, but i think most add one.......
your local parts store should be able to tell you the proper pressure....believe it is 12-16 pounds

[ChopperDr]

Try not to over fill the radiator. Without an overflow tank it will need some room to expand when it gets hot. Is it just puking out the overflow? Will it stop once it gets to temp, or does it continue?

Chop

[malexander44]

It does stop, but I don't know if that is because the radiator is almost empty. After it stops puking and I open the cap I don't see any fluid in the radiator. When I open drain at the bottom maybe 2 liters of fluid drains out.

I just pulled the lower hose to check and see if the hose might be clogged and obviously fluid drained from the pump. After checking the hose I reinstalled it and filled the radiator up again and started the truck until it got hot without any leaking. When I opened the cap again the radiator was still full.

I might be overfilling the rad. Where do you suggest that I fill it to?

Mark

[malexander44]

I would have thought the radiator would have at least a little less fluid in it due to the fact that it would have filled up the pump again, or would that have filled up while I was filling the rad?

Sorry that these questions might sound stupid. I understand that when you fill fluid above a point it will fill in the areas below that, I just thought the pump would not take fluid unless it was turning.

Mark

[protrash64]

I would fill it....drive it and monitor engine temps. If its ok then leave it and dont worry about the level until it cools. Sounds like its just leveling out the system to me. Check it but if its not hot and it stops puking, then its full.

[Fred T]

Radiator fill level is 1" below the filler neck . Have you checked the water temp? I use a meat thermometer. Start the engine with the cap off. When the coolant starts flowing it should be close to the temp of the stat.

[towrecker]

you could also have gotten a bad stat i have got them that either would not open or not all the way a build pressure o and by the way the cap is 13 pounds if you have a v8 radiator 16 with the tiny 6cyl radiator and i got that outa the 63 chevy truck shop manual i was given at the chevy dealer they got tired of me comming to look at it and gave it to me is that not just luck ...heck it was like getting a 100 dollar bill give to me ;-)
jason

[towrecker]

as for your question on an overflow tank i have one on my 63 i just cant remember what it came off of i got it at the bone yard fits on drivers side in the same manor as the battery on the other clears the volt reg and all it was off a mopar but cant remember what kind heck i cant even remember the color of the car now ...been years i say they are all crushed now i will look it over monday and see if it has a part number to cross and take a pic it looks like it grew there ...well like it was factory installed i should say ...

jason

[MacAttack]

Mass produced things like thermostats and caps go wrong all the time - nature of the process.

Remove your thermostat and put it in a pan full of hot water and see if it’s opening. With the cap off and the engine up to temperature - your should be able to see the water flowing.

I was always taught that air is not the friend of your coolant system.

A fresh cap in the 14-16 pound range (each pound equating to increasing the temperature of water from boiling by two degrees Fahrenheit) should keep your rig from over-flowing.

A catch bottle is simple to retrofit and are a very cheap way of keeping your coolant off the ground. Again, with the fluid level up to the minimum ("Cool") level in the bottle and the air purged from the system - it should be okay, if the pump is doing its job and nothing is blocking your engine’s water passage.

Mac.

[malexander44]

Well, it seems like the problem has been fixed. It appears that I was filling the rad too full. I have now replaced the pump, thermo and cap and keep the rad filled to within an inch of the fill spout and it runs like a champ. The temp will get up to about 225-230 then come right back down to 190. While I'm on the highway it runs at 190 all day long.

Thank you to everyone that gave me advice, I REALLY appreciate it.

Mark

[protrash64]