Anti-Freeze seeping out of radiator overflow (1 Viewer)

[Bigstar]

Hi guys. I did a quick search but couldn’t get a direct answer for my question so…..

I checked my radiator level before our weekend freeze and the level was a little low. I topped it off with anti-freeze until it spilled over the top. I started the FJ40 and let it run for a few minutes…. it was only about 5 minutes. I noticed anti-freeze dripping under the radiator. I realized it was coming out of the overflow tank. I pulled the hose and raised it about the radiator fill cap. Anti-freeze started coming out of the raised hose. When I turned off the truck antifreeze continued to flow out of the raised hose. The truck has ALWAYS run cool and never had any overheating issues.
I just went out and checked on it and the water has stopped seeping out of the raised hose.…..

 

[middlecalf]

If you don’t hook that hose back up to the overflow tank it will suck air back into the coolant system and that air will need to be burped back out to avoid cooling issues the next time it’s run.

 

[Bigstar]

Thanks… yeah I stuck it back into the overflow tank when I was done. Is it normal to push out coolant when the truck is started and it’s low idling for awhile? Not sure if that is normal when the thermostat opens or what…..?

 

[73FJ40]

Thanks… yeah I stuck it back into the overflow tank when I was done. Is it normal to push out coolant when the truck is started and it’s low idling for awhile? Not sure if that is normal when the thermostat opens or what…..?

Yes. Without the overflow tank (on older models not equipped with tanks), the factory manual says to keep the cold level 3/4" below full.

From the 1973 owner's manual:

The coolant expands when heated, and if the radiator is full, it has to go somewhere.

 

[B y r o n]

Most coolant overflow bottles have a cold and hot level. If the coolant level is at the hot when cold then it will bleed fluid when it gets warm. As the radiator cools it will suck fluid from the reservoir and the fluid level should come down to the cool level. It may take some time to equalize but it will eventually.

 

[Bigstar]

You guys go have a beer on me! ….. spiritually haha. Your knowledge is appreciated

 

[45Dougal]

Most coolant overflow bottles have a cold and hot level. If the coolant level is at the hot when cold then it will bleed fluid when it gets warm. As the radiator cools it will suck fluid from the reservoir and the fluid level should come down to the cool level. It may take some time to equalize but it will eventually.

When the radiator cools it Should suck fluid from the reservoir...

If you're blowing fluid out and not sucking it back in (resulting in a net loss), then check the seals on your cap - both the bottom and the top seal must make a good seal in order for this to happen (yes - I lost a bunch of coolant this year).