Expansion tank leak

[gcp]

Today I was introduced to a Porsche mechanic who will probably be servicing my 996 (independent shop, we don’t yet have a dealer in Huntsville). He started telling me while inside his shop that the coolant expansion tanks have a tendency to leak due to the way the sensor is mounted at the bottom of the tank. He said it just turns and locks into place without even the use of an o-ring, kind of like a simple twist fit.

And wouldn’t you know it, the minute we walked outside there’s a small coolant puddle under my car. Never noticed a leak before, in the week I’ve owned the car, so I don’t know if it just occurred or I just didn’t notice it (very much doubt it). My question to you is, if this is an inherently (Porsche) bad design, is there an after market tank available out there? Have any of you experienced this problem and if so how did you rectify it permanently? He estimated about 4 hours labor and about $250 for the tank but I am reluctant to give him the go ahead only to have it happen again. :help:

Thanks,

gcp

[Loren]

Yes, this is a common problem (you can find many posts on it here). Porsche is on a fourth generation of that tank. If you post the model year, exact model and whether the car is US/Canada or RoW I will get you the latest part number. There is also a link here to a DIY - likely a 5 or 6 or 1-10 scale.

[djantlive]

4 hr of labor is excessive. I'd say he'll spend 2 hrs at most. I think he's screwing you!

[gcp]

Loren, my car is a 2000 911 Carrera Cabriolet, USA model I believe.

Thanks,

gcp

PS. djantlive thanks for the advise, I'll talk to him about it.

Edited September 27, 2005 by gcp

[Loren]

Loren, my car is a 2000 911 Carrera Cabriolet, USA model I believe.

Thanks,

gcp

PS. djantlive thanks for the advise, I'll talk to him about it.

996 106 147 56 Water reservoir - retail $255.79 (as of Sept 2005). I'm sure Sunset Imports (Porsche Parts at Dealer Cost) can beat that.

[gcp]

Loren, your number is correct. I've already ordered the same from Jeff for $164.43.

Now I'll have to deal with the mechanic's time. Is 2 hours labor reasonable and should I insist on it?

Thanks,

gcp

[slbates]

Get the new cap if you don't already have it. Also, get the new water level switch...it is only $10 and you have to remove the tank to replace it. BTW, your mechanic is wrong. The water level switch on the bottom of the tank is not a "wet" switch and does not need a o-ring. I just replaced my tank due to old age and 98K miles of use. The tank just had a hairline crack along the side. I ran the tank for three weeks with the pressure relief valve in the up position and it did not leak when not under pressure. I changed the tank myself and it took me a solid 2 hours. I used the instructions on this site, with a few mods. Most importantly, place a couple of large vacuum caps over the fuel bungs. You do not want any dirt getting into the fuel system and with all of the wrangling trying to get the tank out, you are going to stir it up.

[gcp]

Guys, since the expansion tank design seems to have systemic design/fabrication problems has there possibly been a Porsche recall on this issue?

slbates, thanks for your suggestions I will order the water level switch and the new cap today. BTW where is the DIY on this? Can't seem to find it. Being new around here are the DIY procedures pinned? Any suggestions on which replacement coolant I should buy/use?

Thanks,

gcp

Edited September 28, 2005 by gcp

[gcp]

Lets try my question again!

"BTW where is the DIY on this? Can't seem to find it. Being new around here are the DIY procedures pinned? Any suggestions on which replacement coolant I should buy/use?"

Thanks,

gcp

[1999Porsche911]

The sensor does not seal anything. It does not even touch the collant. You can run without the sensor and there will be no leak. It simply inserts into a large dimple in the bottom of the tank that, itself, is molded as part of the tank. If it leaks there, it has nothing to do with the sensor sealing.

Edited September 29, 2005 by 1999Porsche911

[TRIATHLETE]

Lets try my question again!

"BTW where is the DIY on this? Can't seem to find it. Being new around here are the DIY procedures pinned? Any suggestions on which replacement coolant I should buy/use?"

Thanks,

gcp

<{POST_SNAPBACK}>

Here you go - http://basketcasemotorsports.bravehost.com/Tank.htm

I just did my 99 C2 yesterday - two hours tops. Getting the tank out was a bear. I ended up pushing it back in and pulling a few more hoses off to finally extricate it.

You will only need a pint of coolant (Porsche brand) if you follow the instructions and reuse what you drain. Good luck.

I'm enjoying the $400 I saved by doing it myself, but this DIY is not for novices - if in doubt pay somebody else to do it.

[gcp]

Thank you very much TRIATHLETE.