What is the chance after an hour or so of long driving with traffic that my coolant leak is the expansion tank? It looks like I have the newer tank, and I don't see anything visible, but the next morning I have a glop of fluid in the snow in my driveway. I just had a new radiator, thermostat and water pump put in, and see no leaks around there.

2002 S.

 

Meant to put this in stock issue, moderator can you move it?

Thanks!

 

Sounds more like a therostat housing leak but you say it was just replaced. If it is the expansion tank you should be able to see wet coolant or white dried coolant on the tank usually at the center seam. Maybe pop off the tank from the mount and look at the bottom hose just to make sure it is not leaking after all the cooling system work.

 

If you just had all of that cooling system work done, take it back and have them fix it! Something was probably not tightened properly.

 

Possible you might have some pinhole leak(s) in the hose somewhere?

 

I had a coolant leak on my 05 S fixed three times under warranty. This Fall, it started again, so I decided to repair it while I was replacing the leaky motor mount. What I thought was a leak around the thermostat housing turned out to actually be the brass temp sender. The teflon tape around the treads was green and hard, so I simply removed the sender, re-taped it with new teflon tape and it has been fine ever since. Since you had the work done, I'd have the shop look into it, but find it strange that it was'nt noticed.
Was also surprised that the Bentley manual failed to mention two addition sensors that had to be removed just to get to the housing and sensor.

Good luck.

 

Hopefully they didn't nick one of the orings when they changed the water pump.
It a week after I Changed mine for it to start to leak. Good luck tracking it down. wipe everything down, drive it and start looking for antifreeze or dried white residue.

 

Thanks, yep, at least it is not leaking in the car at the heater core right

 

Took a while, but the leak finally manifested it self, first thought the car was on fire, then smelled coolant through the vents. Nice to know I can still overheat when it is 30F outside! I was stuck in traffic and with all the snow here in Boston, was not able to pull to the side, had to wait a bit and kept an eye on the gauge for about 10 minutes, next thing I know the teeny tiny red light is on and the gauge is pegged!

You would think I would get a ding or something.

Anyway I was right next to a spot to get out of the road and I shut off the car. I turned it back to ACC mode and I could hear a fan running before that. Now the red light flashed on the dash, and slowly the gauge went back to the "normal" position. After waiting for about 10 minutes, I started the car, let it idle for a few minutes, was able to get back on the road and home going about 30-40mph (traffic) the rest of the way.

As soon as I pulled in the driveway and let the car idle, it started smoking again. So I popped the hood, and pretty obvious the seem is leaking in the expansion tank.

So where is the best place to get one of these, and should I go for the aftermarket steel one?

How tough are these engines, assuming I didn't see the red light for the engine temp right away, I figure at most it could have been a minute or so, or best case the light just went red and subconsciously I saw it and looked from the corner of my eye.

Thanks!

 

Here's a source for an aftermarket tank. Good luck.

 

Thanks, after the cool down, it was another 35 minute drive home, and engine felt fine. Ordered a new tank last night.

 

Can you see a date code molded into the expansion tank?

 

On the new or old one? I am at work now, but if it is still light when I get home I will check.

Why do you ask?

 

So I looked, and I am guessing this is the original tank, which surprises me, but I assume newer design as it is yellow, maybe just aged?

It has 2 wheels, one starts with 01 to 06 and the 2nd one is 1 thru 12. The arrows point to 02 and other point to 6. My car was manufactured 7/2002

So if this lasted almost 10 years, I don't feel bad about making the decision to replace it with the 34 dollar original tank rather then spend $140 on a metal one.