San Rensho

2000 2,7. I'm getting a slight coolant leak; condensation on the trunk. I changed the bleeder valve and now it stays in the up position when the car is hot. Is it supposed to do this and it is the source of the leak?

insite

this is normal behavior. that valve isn't just for bleeding the system, it's a pressure regulator. when the coolant gets hot, some of it vaporizes. vapor is a crappy heat conductor, so the system is designed to vent the vapor into the overflow tank, keeping the system primed with liquid only. when the car cools, a vacuum is created in the system that then draws liquid from the tank back into the system. that 'bleeder valve' regulates all of this, and will be in various stages of open/closed while the car is warm.

also note that this setup means that the system is self bleeding. once the initial bleed is done when the coolant is filled, any remaining air will be purged through the overflow tank.

sometimes you will get vapor condensation because the reservoir cap itself is bad. porsche actually changed the design somewhat, so you may want to replace it as well.

San Rensho

Thanks. Great explanation. I got the new cap and still get some leakage. I just hope its not the dreaded coolant tank leak.

insite

if your car is a 2000 and you haven't done the expansion tank yet, just get it out of they way. you're on borrowed time.

Dale_K

There are 2 o-rings under the base of the bleeder valve that might be the problem. I put a new cap and bleeder valve on my 2000 S and still saw condensation. Totally dry after doing the o-rings. Here are a couple pictures I took when I had the bleeder valve body apart.

San Rensho

Yikes. I just found coolant leaking out of the coolant tank and into the trunk. Not looking forward to digging the tank out and replacing it.

Macster

The tank can be a pain to replace. I had no place to work on my car when its tank failed and gushed hot coolant out just ahead of the rear tire so I took it to a dealer.

Tech said the job was not hard but 'fiddly'.

But there are several DIYs articles on this around. One trick is to buy the right tool to unclip/loosen the hose clamps. That's all I know. Check with DIY articles for more reliable/accurate info.

Sincerely,

Macster.

San Rensho

Thanks, I looked at pelican and pedros and it looks doable. Definitely getting the special tol to remove the clamps.

insite

yeah, that tool is a must-have. mac's right that the job isn't difficult, but it IS a knucklebuster.

San Rensho

I guess I'll consider the tank replacement as my initiation to Boxster wrenching. Anyone know of a source for a cheap tank? autogeek has one for about 250.