Zoomspeed

I found out today that I have a coolant leak. It leaks from the undercover area on the passenger side underneath the headlight.

It only seems to leak after I turn off the car so I suspected the overflow tank, so after I had turned off the car today it was dripping. Then I took a some water and poured into my overflow and water started pouring out from underneath the car.

I looked in the service manual to figure out how to get the overflow out but I can't find it.

Here are my questions:
How do I get the overflow tank out?
Is it a pain to get to?
Is there anything else in that area that it could be?
If it's a crack in the overflow tank could it be repared with anything (i.e. superglue, JB Weld, silicone sealent, etc..) or should I just replace it with a new one?

Please hurry with your help. If someone can help in time for me to get to school then I'll overnight you a sandwich from work!

Thanks

badass7

That doesn't sound good at all! Usually that means your coolant seals have gone out on you. However, I hope that is not the case for you!!

Sidestick

iTrader: (1)

No need to take the tank out, I don't think it's the problem either. I had the same problem. It was due to a faulty Pettit aluminum AST, ended up eliminating AST altogether. Do you still have an AST? If so try replacing the cap.

At the worst, as badass said, could be your o-rings. Sorry.

Zoomspeed

I have the pettit AST as well. I poured water directly into the overflow while the car was off and as soon as I poured the water in it started coming our from the area right under the overflow tank.

How could it be a fualty AST or o-ring? The AST is on the other side of the car, and for the water to get to the o-rings from the overflow the car would have to be on and sucking in coolant from the overflow right? Please correct me if my reasoning is flawed though.

Thanks

spooledUP7

I can't really see how the AST could be flawed unless the filler neck had been distorted when welded on, or if the overflow nipple had a small leak.

By itself, the AST could cause a problem like you describe if the filler cap is not holding pressure. Either the filler cap on the engine, or on the AS could cause the same scenario.

One lesson I learned about pressure and filler caps is that you can't really tel just by looking at them if they have gone bad.

Just replace them and I'm sure that this will fix your problem.

You will also want to look for any signs of a slight coolant leaks such as: Heater hoses, throttle body hoses, radiator hoses, overflow hose, Lower AST return hose, and anything else you can find.

If you are leaking any amount, then your overflow tank will not return as much coolant, or none at all because the system would have decompressed. So, you can see that if you are constantly overflowing but never returning then you will end up with a mess on your driveway.

chrislloydus

If you are keen to remove the overflow tank its quite easy ( and if you havent got a turkey baster you will need to remove it to drain out the coolant to bring it back to the F mark anyway).

Jack the car up securly, remove the road wheel, and remove the inner arch completely - its possible to get it out withough it completely removed, but for the sake of 5 mins work.......The inner arch is held in by those plastic clips that you unscrew the centre out of then pop off. The edge of the arch is held by phillips head screws.

The overflow should be obvious (see attached piture at bottom of this post). Disconnect the filler tube from within the engine compartment (one 10mm bolt - then pull upwards), then disconnect the pipe in the top of the overflow - it sits in a rubber grommet and can be persuaded out. Then theres one 10mm nut, one 10mm bolt holding the tank to the chassis. Undo these (the tank will still be supported) then pull the right side of the tank out first, followed by the left. Ta-da ! one removed tank.

Set the tank on a level and put the filler neck back on , then drain off the excess fluid , using the dipstick to check the level.


Check the pic

Zoomspeed

I'm getting a little confused. How do the pressure caps affect it if the car is of and the sytem is not pressurized?

Theres only 2 ways into the over flow: The overflow filler neck, and the line that goes from the bottom of th AST to the overflow right? Assuming theres nothing wrong with the overflow. If I pour water directly into the overflow when the car is off and the system is not pressurized The only place it could come out is the filler neck right? But its not coming out the filler neck. So wouldn't it have to be the overflow?

ech

the system is pressurized - when the fluid is pumped and when any air in the system expands, or fluid boils. That is why the radiator caps have 0.9, 1.1, and 1.3 bar on them. Pressure ratings.

If the cap is bad then coolant can get past the cap on the ast and flow into the overflow tank.

If there are leaks in some hoses, then air can get in and expand under heat soak. Sometimes there are leaks or problems near the heater core.

If you have bad o-rings, then gasses get into your system and displace coolant. After your turn your car off heat soak expands the gasses.

check the things that are cheepest first.
1) all hoses/lines, esp by heater core. Should be able to sniff for coolant and look for residue.
2) replace caps - just for kicks
3) start to check for bad o-rings. Car hard to start in the AM? More white smoke than you used to have? What does your exhaust smell like? If coolant, then :-(. Have shop run an emissions sniffer on the overflow tank - to see if exhaust gasses are in there.

best of luck.

Zoomspeed

gsrx1000, you were right. I just overfilled. Damn my paranoid self. Thanks

Thanks everyone for your replies. Even though what you guys brought up was not the case this time (and I hope if never is) Its good info to have incase bad things start happening.

Thanks everyone