Thank I’m advance:
my issue starts with when I turn the car on and I let it warm up when I get ready to leave I would have coolant on the floor from the over flow tank.

so I did some research on the forum and found that this could be caused by a broken water seal or air in the system.

so I bought a Lisle funnel system to do a champagne test. So preforming the test I got a few bubbles to come out in the beginning of the warm up but they did stop. I let the fan come on a few time and also i had the heater on full hot and on four. And I also disconnected the coolant line going to the TB also.

too make sure I have everything set up correctly:
i have an AST with my pressure cap on it.
the funnel set up is on the filler neck on the thermostat housing.

so the question after the whole explanation is when I turnt the car off I had some bubble come up. Is this normal or just mean I have to cycle this process a few time or do I have a issue?

Again thanks in advance for the help.

 

Simple things first:

-- with the engine cold, where is the coolant level in the overflow tank? Between the F and L marks on the dipstick?
-- are the hoses to the filler neck, AST and overflow tank connected correctly?
-- is the pressure cap still good?

 

— it’s on the full line.
—from my understanding yes they are correct but I will double check in the morning.
— the one that’s on the car right now is new. And of course it could be bad out the box.

when this issue started I thought I just over filled the overflow thank but after it over flowed a few times I thought it would level out just never did.

 

If your problem only began after putting on the new cap, can you switch back to the old one?

Here are the factory AST lines:

 

no I had the issue before that’s why I got a new one. It I’m 99% sure my lines are right but I’ll double check in the morning when I get home from work. Thanks for the diagram.

 

The other possibility is the line going from the AST to the overflow tank has a small leak. That line has to be air tight.

As the cooling system warms up, it expands. Some of the coolant is pushed out of the system through the radiator cap to the overflow tank. As the system cools, it sucks coolant back from the overflow tank.

The overflow tank has to be at the Full line on the dip stick, if you just fill it up randomly the coolant that the system pushes into the tank will overflow the top of the tank. Also if the hose going from the radiator cap nipple to the tank has to be air tight. If it isn't the system can push coolant out but ends up sucking air in through the hole and not sucking coolant back in.

The overflow tank has a hole on top by design, if it is too full it will come out of the top of it.

Dale

 

Just got done double check the routing of the lines. And I’ll double check if I can find any of the issues that you brought up Dale. Thanks again gentlemen for the help.

BTW I think I’ll be deleting the AST sooner then later now.

 

Another quick. Could a bad seal on a no pressure relief cap cause this issue?

 

Possibly, if the seal failure allows air to be drawn in as the engine cools but still prevents coolant from leaking out when the engine is hot.

 

If you mean the non-vented fill cap, then yes. Air might be sucked in as the system cools (not pulling coolant back from the OF tank) w/o leaking out as it gets warm.

Also, internal engine coolant seals can leak one way and not the other - in your case, letting combustion gasses into the cooling system w/o letting coolant into the combustion chambers. That would force coolant into the OF tank and cause your low-coolant and tank overflow symptoms.

 

I think this is the issue I may be having. Does anybody know the part number for this? Do you think I could find this at a normal parts stores?

 

The 2 caps:
-- thermostat housing/filler neck cap KF 01-15-205. I've also seen it as KF 02-15-205. I think it is unlikely you'd find it at a general auto parts store, but you might. EDIT: Advance Auto's website sells both types of caps.
-- 0.9 bar AST pressure relief cap N3A1-15-205A. Generic replacements are sold at most US auto parts stores.

In a pinch, I suppose you could use either cap on the filler neck and it should seal properly, but only a pressure relief cap should be used on the AST.