Car doesnt suck coolant?

[Turbo Juice]

when i go WOT or i am on the highwayfor a while, my coolant boils over. the problem is that my car doesnt suck the coolant back in from the overflow tank.
i occasionally have to top off the system by pouring in more coolant, but the overflow bottle is always all the way filled up.

i have a different over flow tank that i got form autozone, but it is set up properly.

whats up with this.

 

[silver eclipse]

Your radiator cap could be bad, but more importantly is why are you haveing to continually fill up the fluid. Maybe its shooting back in, and overflowing, thats why its always full?

 

[Turbo Juice]

also i have a greddy rad cap, not too old 170 deg thermostat.

well in the cold it is real obvious that i am low on fluid because there is no heat at idle. so even just cruising around town it wont suck any back in. also my temps never go higher than 210, so i dont what reason it has to overflow.

 

[1990talon]

You prbably have a small leak. pressure check the cooling system

 

[silver eclipse]

If its boiling out, either its over heating or not holding pressure. Do like 1990talon said and pressure check it.
You maybe loosing a small amount from a bad water pump. It will drip out of the weep hole. And it maybe hard to find due to timing belt cover, pulleys and etc.

What pressure is that aftermarket cap rated for, It needs to be almost exactly the same as factory.

 

[Turbo Juice]

the rad cap is 1.3 bar.

there isnt a water pump leak. and as for pressure. the hoses get pretty hard woth the car on. and they release a lot of pressure when i take the cap off.

 

[sawnuoff]

usually the only time it sucks from the overflow bottle is when your car is cooling down, like overnight, i dont think it will just driving around town.

 

[silver eclipse]

Thats like 19 psi, thats kinda high. but other than that, if theres no leaks then youll have figure out why your loosinf it. thats the first key.

 

[silver eclipse]

Did you figure it out yet?
-Chad

 

[fp-green-95tsi]

You are running a coolant overflow bottle not a catch can correct? It does have the tube inside the bottle for recirculation correct? It should only draw the coolant back in when the car is cooling down.

 

[laserspeeddemon]

You could have a HG problem, this will cause boost to leak into the coolant lines and force coolant out of the system.

 

[spoold96tsi]

You could have a HG problem, this will cause boost to leak into the coolant lines and force coolant out of the system.

Or dump coolant into the cylinders

Id suggest pressure testing. You could just have an air pocket too.

 

[dieseltech]

I have a similar problem with my n/t car. The rad light came on awhile back so i filled it up, all 2 fl oz, . then i filled the overflow tank to the proper level. The light came back on and so I checked the overflow tank. Completely full, odd. I'm planning on pressure checking it soon.

 

[Turbo Juice]

so far i have not figured it out. the car is still overflowing coolant.
i have an overflow bottol from autzone mounted in between my fise box and intake cone. the coolant goes to a nipple on the bttom of the bottle so i know it is set up properly.

i thought it may be the headgasket. it was just replaced less than 10k ago and compression is good. there is no milshake in my oil and my coolant is minty green. no hint of brown.

so i am lost as why it is always overflowing.