Coolant Leak / Overflow ???

[Lil bastard]

Originally Posted by Boxtaboy

Agreed, but he hadn't lost all the coolant in his system, so topping up with distilled water and driving the 30 minutes to the dealer (which was what he was asking if it was safe to do), would be fine. There was a friend of ours who during a 9 hr. drive down to a Boxster event in North Carolina from New Jersey, his old coolant cap let out a huge amount of coolant after stopping. Refilled with (non-distilled) bottled water and went on to go thru the whole 4-day event, and then drove all the way back home, with no issues. Car and water pump are still fine today....

Not to put too fine a point on it, but you stated that with " 'just' (sic. only)distilled water you can drive the car safely". That was the basis of my disagreement.

Your friend has added bottled water to the system, but it wasn't completely dry from your description, nor would I expect it to be from just a failed cap. So, while diluted, I suspect there was still sufficient coolant in the car to lube the pump, etc.

[D.L.]

Not to hijack this thread, but my coolant levels are sometimes low causing the light to blink on the dash. I think I may have a small leak or a bad cap because I find A LOT of condensation above of the coolant area on the trunk. I always thought this was normal due to changes in temperature, but I guess not. Anyways, I always used regular water to refill... Did I mess up the car doing this, or should I use coolant to refill? I also heard that Boxsters use a different type of coolant. Is there special coolant for our cars?

[Lil bastard]

Originally Posted by D.L.

Not to hijack this thread, but my coolant levels are sometimes low causing the light to blink on the dash. I think I may have a small leak or a bad cap because I find A LOT of condensation above of the coolant area on the trunk. I always thought this was normal due to changes in temperature, but I guess not. Anyways, I always used regular water to refill... Did I mess up the car doing this, or should I use coolant to refill? I also heard that Boxsters use a different type of coolant. Is there special coolant for our cars?

A Lot of condensation isn't mormal. Suspect a bad cap, a poor Bleed Valve seal, a bad hose connection or a cracked coolant tank.

It's OK to top up occaisionally with water (distilled water is best to prevent introducing minerals to the system).

But, each time you do this, you dilute the coolant mix. Porsche specifies either a 50/50 mix of anti-freeze/distilled water, or a 60/40 mix. You don't really want to be <35% anti-freeze or you both increase the corrosion potential and reduce the lubricating properties of the mix.

Over time, topping up with even a little bit of distilled water on a semi-regular basis adds up. You can buy a cheap Hydrometer at most any auto parts store for about $5. This is the little 'baster' which has the little floating balls in it. It tests the specific gravity of the coolant mix and can tell you what your actual mix % are.

The coolant should really be changed every 5 yrs. or so, despite claims from Porsche that it's a lifetime fluid - it isn't.

Use the search function here to find out what brands are, and are not, compatible. There's lots of good info.

[rick3000]

Just a quick update:

I talked to the Porsche dealer today, and they said they couldn't find anything obvious wrong with the car. The coolant tank was fine, all the hoses where fine, and that the problem could be only one of two things. One it that the instrument cluster was showing a bad reading and that the complete coolant drain was a weird occurrence.

The second thing it could be, is the water pump. The water pump drains out of the coolant overflow above the right rear tire (where I saw the coolant come out), and it would cause the overheating at low speeds, and not high speeds that I have been seeing. This explanation fits all the symptoms of my problem.

Here's the problem. If they pull the water pump out and nothing is wrong, I get stuck with the bill. If something is wrong then I don't have to pay anything except the deductible.
Has anyone replaced a water pump, what did it cost?
What is the likely hood of it being the water pump?

Thanks Everyone!

[juan986]

I replaced the water pump, got it from ebay for $100 and my mechanic replaced it for $160. Its very simple, not too much work involved.

I had the same problem, my water would drain out little by little, it would take about 1 week and a half and then the blinking light would turn on and tempereture started to raise.

[Lil bastard]

Waterpumps do fail, fact of life. A '99 means the pump is now 8-9 years old. At that age, it's not unusual regardless of mileage to have it fail.

It's a pretty easy DIY. I personally would not pay to have it done. The pump runs about $300 (cheaper on eBay), not sure if there's a rebuild kit for one, but if so, this is also an option. A rebuild consists of replacing everything but the actual casting. Seal, Bearing, Shaft, Impeller are all new. Usually the shaft needs to be pressed out and the new pressed in - I've had NAPA machine shops do this work for me in the past for under $50 with good results. You'd also need a new gasket - $8 which has to be cut because it is also the gasket for the Oil pump - an easy modification. Then you'd need 2 gal. of coolant and 2 gal. of distilled water - say $30 max. If I were going to that trouble, on a '99, I'd also change out the 'T'stat - another $15 incl. gasket.

[rick3000]

That's what I have been reading. I think I will just tell them to check the water pump. I would DIY except with the warranty, it isn't worth $300 out of my pocket, when there is almost a 90%+ chance it is the water pump, so it will be covered.
Thanks for all the help, and I'll let everyone know what happens.