1983 f350 reservoir tank fill lines

[carl christensen]

so my tank only has markings up near the top that ,, says hot fill line...nothing on bottle says cold fill line..just how much coolant should be in the tank when cold

 

[MtnHaul]

Do you have a cooling problem or just wanting to be precise?

I don't know the answer to your question, but I do know that you don't need a coolant overflow or a 100% full radiator. No coolant overflow bottle for the last 3.5 years and no overheating with a slightly under-filled 2-row aluminum rad. YMMV

 

[snicklas]

I’m not 100% sure either. But, you could make sure the radiator is full, get it to operating temperature (thermostat opened) and fill it to the HOT FILL mark....

Just make sure you have at least some in the bottom, and the hose is pushed all the way to the bottom... that way you don’t suck air in instead of coolant.

Also, until they went to the pressurized degas bottle, the coolant tank was more of a pollution control than anything else. In the 70’s and earlier, there was just a hose run down the side of the radiator and what ever came out just dripped on the ground. You will fill it up and once all the air was worked out, it would find it’s own “full” which normally isn’t up to the neck..... the coolant recovery bottle was just that.... to keep it from dripping out on the ground. It does have the side effect of allowing the system to draw coolant back in..... but I don’t think that was it’s real design purpose. I worked on a 56 Packard for a lady and it hadn’t ran in a bit. Someone had filled the radiator completely full after the last time it had run. once I got it running, the “extra” dripped out on the ground. My oldest (25) was worried something was wrong and we had a leak. He is used to the “newer” vehicles (his DD is an 86 IDI). I showed him the hose and explained how it worked....

 

[Philip1]

I'd at minimum make sure the hose going into the overflow is covered that way you know that the radiator isn't pulling air when it is cooling down. I agree with snickles about the best way to fill it would be to get the engine to operating temperature then fill it to the hot full mark.

 

[Booyah45828]

Cold or hot, just fill it to the hot mark. It will find it's own level.

As snicklas said, it's not really "necessary" but is nice to have. I've seen a lot of the older cars with that hose pushed into coke bottles, milk jugs, or any other container to catch the overflow and return it back when cold.

And for a car to pull coolant back in, it has to be air tight from the radiator cap to the bottle. Some vehicles aren't, so they'll be an inch or so of air at the top of the radiator. No problems caused by that either.

 

[carl christensen]

thanks guys