Have a 2004996tt x50.Taken the car out for a couple of drives and notice a slight coolant odor after shutting down. Coolant level drops very little after a few hours of driving. No sign of coolant on garage floor and no white exhaust at start up or while running. Any thoughts would be greatly appreciated. Have owned Porsche cars for almost 20 years, this is my first water cooled.

 

I'm no expert but I have asked this question before and was told it is not unusual at all. If you aren't leaking at all, maybe it is residual odor from a fill?

 

Thank you for taking the time to respond. Would have considered that but I have yet to add any coolant. Bought the car mid January and trailered it home. Have just started to drive it a couple of weeks ago. Being our fifth vehicle and basically a sunny day ride it doesn't get driven much......yet :-)

 

Coolant is not considered a consumable, radiators, are more than likely at the top of the list to check. They do go bad, and leak at the seams. The o-rings in the clip in hoses can leak as well. Then there is the coolant tubes in the rear, which go from sealed to dislodged pretty quickly.
I would inspect both for signs of coolant residue.

 

Will do...thank you for your input!

 

I had coolant smell for a long time, until I decided in 2008 to do a proper inspection of the engine. Took out the airbox and the alternator to found one of the coolant pipe from the water pump housing leaking. It did not pop out due to restricted space and there was no leak on the floor because the coolant was evaporating on the engine block.... I also had the left radiator top plastic cover leaking but I had drops on the floor in that case....

 

There is likely a more noticeable leak to come. In my experience this was two radiators. Take a sniff around to try to determine what end of the car it's coming from. If the front, take off the bumper to inspect. Front bumper removal is very easy.

 

Starting to collect parts a few at a time until the car comes off the road next winter. Will be removing engine/tranny for maintenance. One of the jobs I will do is properly sealing the manifold nipples as I understand this is a potential problem. Hopefully I can drive the car this summer without any major problems .Thank you for sharing.
Al

 

i am also in the camp that believes you have a pinhole ( or larger ) leak in a rad.

 

Will do just that....sniff test.......(dog does it all the time) Hopefully all will hold together until fall. Have plans to remove the engine/tranny and address all potential problems at once. That should give me a few years of trouble free enjoyment. Do appreciate you taking the time to respond.
Al

 

Have yet to see any coolant on my garage floor....my 930 marked its territory for years....the 996tt...nothing..yet

 

I agree with the others. There should be no coolant smell at all. You most definitely do have a leak somewhere, and it will eventually let itself be known. Potentially in dramatic, though very unlikely catastrophic, fashion.

I'd check the easy things first.

1) Front radiators. The give away to this is a strong coolant smell coming from near the front wheel wells. Note if there's any moisture at all near the bottom leading edge of the wheel well. A simple front bumper removal will also reveal this clearly, and you might aw well, to clean out the front radiators of built up debris.

2) Coolant expansion tank cap. These should be screwed on tighter than you're use to on other vehicles. They will leak if not closed tightly enough. But they have also been known to fail.

3) Coolant expansion tank itself. If it's very yellowed, this would be a good indicator that it is likely. The coolant tank itself has been known to get hairline cracks, especially on its hidden fender facing side that you can't see unless removed. Leaks only when the coolant system is nice and hot.

4) The multiple coolant fittings. 8 of them. Though the 2 elbows are the typical (though not only) ones to fail. One to the right of the hydraulic pump. One behind the alternator.

 

With all this in mind, will take the car out for a drive over the next couple of days, get it up to operating temp temp and see if I can hunt down the leak or at least the source of the coolant smell. Do appreciate you taking the time and effort to respond
Regards
Al

 

When you have the motor pulled, don't forget to get the whole cooling system " press flush " so insured you get all the air out. Coolant also ages / with all the cycling of the temps. . As explained to me by my Master Porsche tech. Some say it's ok to simply fill and drain. Pressure flush is what the Porsche dealer process.

 

weaping radiator core is my bet, but a good time to look around and inspect all of the system.
It is not normal to have any coolant smell or usage.