Aftermarket coolant over flow tank

[Nightstang00]

I am switching to contour fans, and got a coolant tank online from amazon. Seems to be highly rated but i filled the stock reservoir up to cold and poured it into the new one and its almost filled up. I’m concerned that it will not be able to take the hot level of fluid based off the line level on the stock reservoir.

Would I just be able to fill the raditator up and not the overflow reservoir? It’s from a 93 5.0 5 speed.

The more I think about it , I don’t remember seeing any coolant in the stock overflow tank when I removed it. The after market overflow is 800ml.

 

[Mustang5L5]

It just needs to be sized enough to handle the expansion of coolant.

I run this one, which is 1qt.

https://www.summitracing.com/parts/sum-g1476

It still works fine even with my larger 3-core radiator and more fluid volume. Level only rises an inch or two when heated.

 

[Nightstang00]

It just needs to be sized enough to handle the expansion of coolant.

I run this one, which is 1qt.

https://www.summitracing.com/parts/sum-g1476

It still works fine even with my larger 3-core radiator and more fluid volume. Level only rises an inch or two when heated.

how would I be sure if the one I have works currently ?

 

[Mustang5L5]

I'm more than confident it would. Install it, run line to the bottom of tank and fill to 1" or so depth of coolant with radiator topped off.

Run engine til warmed up and note how high the coolant rises. Add coolant to bring the level up to a height you are comfortable with.

I have mine set so full hot is about 2/3 up.

 

[Steel1]

I've have an aftermarket overflow on my 93GT for quite a few years now.
Forget brand but it's about 2" in diameter and about 12" tall, full hot I only get about
an inch or two in the tank, seems to work fine.

 

[Nightstang00]

I'm more than confident it would. Install it, run line to the bottom of tank and fill to 1" or so depth of coolant with radiator topped off.

Run engine til warmed up and note how high the coolant rises. Add coolant to bring the level up to a height you are comfortable with.

I have mine set so full hot is about 2/3 up.

Thanks man. Didn’t want anything blowing up hahah

 

[Wayne Waldrep]

You coolant overflow experts should tell us regular folks about why it's not good for the reservoir to be empty. I'm thinking it could eventually draw in air and mess up the system....correct? Or not? And by mess up I mean make the already inaccurate stock temp gauge read even more wonky because of an air pocket.

 

[Mustang5L5]

Correct. When the coolant cools, it contracts. It draws from the overflow. If the van is empty, it pulls in air.

Usually as the coolant expands, the air gets pushed back into the bottle, but not always.

Ideally, set it up so that full cold you still have coolant in the bottle. That guarantees an air free radiator