Airflite40

I have been keeping an eye on the cooling ability of my 951 ever since I bought it.

On sunday I noticed the Coolant Reservoir was spewing coolant from around the cap.

I took the cap from my 924S which looked much newer than the one on the 951 and swapped them.
I also topped up the coolant at the same time.

The car seemed to be holding temperature much better and not running so hot while idling, with AC on etc.

Then I turned off the car and went inside. Come outside 20 minutes later, and puddle of coolant under the front of the car.
I look underneath and its dripping directly from the bottom of the rad.
FAWK!!!!!

I turn the car on and kick on the a/c to see what happens.

The DRIPPING stops.
So I go for a drive for about 15 minutes, stop n go traffic, still running like normal.

Then I stop at a store, turn of the car, go inside. 15 minutes later, come back out and its dripping coolant again. Turn on the car and the drip stops.....

BTW I have no white smoke from the exhaust, no milkshake in the oil....

??????

Keithr726

Early 944s (924S also) used a different cap.

http://www.pelicanparts.com/catalog/..._pg1.htm#item4

Airflite40

But neither one is a stock cap, they are ones that you would buy at FLAPS.... lets swap them back and see....

UncleMaz

How are the tongues on the coolant resevoir cap screw/plastic neck? I think that plastic wears down as mine is not the tightest fit.

Airflite40

They are fine.....I want to replace my reservoir with a new one anyway soon since I cannot see anything through mine.

Both caps look identical, both are 16psi and one says "STANT" and the other one is generic.
The STANT one looks newer.

I swapped them back and it no longer drips coolant but it runs noticably hotter now.

DarylJ

Tighter cap presenting a small leak in your rad when it's at it's highest pressure (after you shut it off) maybe?

Try going to autozone or similar and get a free tool rental of a cooling system pressure tester. That ought to tell you a whole lot.