Dumping coolant - 986 Forum - The Community for Porsche Boxster & Cayman Owners

As I was pulling into my garage, I hear this odd rushing sound and wife tells me I am dumping fluid. Gauge reads just over 180 as it has as long as I have owned the car, going on three years now. Not oil mind you, but coolant. Anybuddy have a clue to what I am up against? I have distilled water to replace some of it but will have to get more to drive it to a dealership. Frustrated in New Paltz, AkL

[QUOTE=Allen K. Littlefield]As I was pulling into my garage, I hear this odd rushing sound and wife tells me I am dumping fluid. Gauge reads just over 180 as it has as long as I have owned the car, going on three years now. Not oil mind you, but coolant. Anybuddy have a clue to what I am up against? I have distilled water to replace some of it but will have to get more to drive it to a dealership. Frustrated in New Paltz, AkL PS Car is '02 2.7 TIP 44k mileage. Leak is in front of right rear wheel.

The latest coolant cap update ends with a .03- what is your cap's part number? Other than that, how was the trip to Hershey?

In front of the right rear wheel is the vicinity of the water pump. There are several hose connections in that area also.

Bad hose, bad coolant cap, cracked coolant tank are the three most likely with your year and mileage. If you have coolant under the rear trunk carpet it's the tank. I think Pedro has a DIY for the tank on his site.

Allen, I'm facing a similar problem (See thread "Mysterious coolant leak"). In my case, coolant is dumping around the right rear axle area, which seems to be an overflow from the expansion tank. We replaced thermostat, pressure cap and bleeder valve, but that didn't fix the problem. Two possibilities: 1/- Air pocket in the coolant system expanding with the heat, pushes the coolant up thru the pressure cap and overflow. Solution: check that the coolant system is purged from any air, thru the bleeder valve (Use "vacuum method") 2/- The dreadful but less likely head gasket leak (seems to be a favorite among some in the industry). Have exhaust gases analyzed for water vapor and coolant analyzed for presence of hydro-carbons. I'm not an expert, but this is where I'm at right now. I'm getting the car back to the shop tomorrow to investigate the above possibilities. Good luck and let the rest of us know what you find out. Alain

And I like explanation #1 better, because it's a lot cheaper to fix, and also it may explain why the problem I have is intermittent. Indeed, depending where the air bubble is trapped, it may be exposed to higher or lower temperatures, thus resulting in more or less expansion. I assume the air bubble would move. Again, I don't know much about engines, but...

I test drove a 2004 S with less than 20 k. After driving about 10 miles and parking, roughly a cup of coolant dumped on ground near right rear. The over flow tank showed way more than max fluid level in the tank. The reservoir cap was tight and the carpet in the trunk felt dry. The dealer mechanic racked it and could not find a source or repeat the problem. I love the car but this is a bit of a red flag. Dealer is offering a 30day 100% warranty and a 5 day 100% refund. Worth the risk?

I had the exact same thing happen to me. I pulled into the garage, shut the car off and all the coolant drained out. I freaked out and took it to the dealer and $600 later nothing was wrong. It was just an air bubble in the coolant tank, and it all drained out of the coolant overflow above the right rear tire. Refill the coolant and don't worry about it.

Part # ends in .01 and upon examination shows no cracks. Trip to Hershey was great, didn't get much as what I wanted wasn't on sale anywhere. Did get to talk with Charles Navarron from L&N Engineering about the engines and their problems. Never saw so many 914, 356 and 968 cars in one group before. Met only one person I knew and he was from my region, HVR. Missed everybody at Dennis from PA's booth as the number was listed wrong. Felt like I was waiting for that Froggy guy, Good Dough! AKL

my car was leaking coolant for a couple days. It would drip out when I pulled into the garage and shut the car off. not much - maybe a tablespoon worth. i had it in teh shop the next day for a vacuum leak and they looked at it. they said my water pump was failing. car has 75k miles. ever since then, it hasn't dripped at ALL. so it's apparently "fixed itself".... mine was dripping in front of the right rear tire too - which is around where the water pump is...

Cap has no cracks and last digits are .01, not .00 which is supposed to be the troublesome one. Pulled up carpet and no water at all. Hoses connecting to the tank look tight and no drips. Put in about 1/2 gallon of distilled water and the plastic tank came up to half between low and high lines. Let sit for awhile and checked again, no water drips anywhere and none underneath. Really turned the cap down tight as I could and went for a very local ride to get car up to temp. Car came up to just its normal spot of about 1/8" above the 180 mark. No water drip at all. Checked when back in garage and found no water under plastic tank or underneath. Water in tank has dropped a bit below the low mark on the tank. Called dealer repair man and he offered no insight. Called local P-car mechanic and he said the tank could be bad internally which could cause the problem. Will be gone until next week on business in Phila. When I get back I will drive it some more and see what happens. Wish it was something obvious like a cracked hose or visible split in the tank. Thanks for all the help so far. AKL

I had something similar happen.. I was sitting at a stop light on my way to court for a ticket.. i saw some white smoke coming out of my taillights, then stopped the car, got out and saw my car dropped almost all of the coolant.. i was able to drive it down the block to a gas station before the engine overheated. I had the car towed to the Highland Park Porsche Dealership on the Northside of Chicago. The car was diagnosed with a broken "Trans-coolant Valve" A $50 part that regulates the flow of engine coolant into and out of the engine. They replaced the part for about $600, then pressure checked the system and my water pump went, which cost me another $1000. My first bet would be a hose, or similar to mine with a broken valve. Did your wife see the puddle after the engine was off? It could have broke when the engine was being turned off so you did not see any white smoke/vapor like i did. Just my experience and .02

Wife got out to open the garage door when she noticed the trail down the driveway of coolant. She mentioned that we were losing something. I then pulled into the garage and shut the car down. Never went over 180 and no red light flashing. I then got out and looked under the car and watch it dump more fluid. So far, as prior post, it ran today with no issues. I will try the cap first and take it from there. Thanks to all for their stories on this problem. AKL