Coolant Cap Poll

[JFP in PA]

Originally Posted by Speedy2000

Im in the same boat, would someone please shed some light

The system has a vent line that runs under the car, when the system pressure exceeds the cap pressure rating (which drops from its original 18.2 PSIG over time and with use), coolant goes out the vent and onto the ground. Now that there is air space in the surge tank, air starts circulating in the system, and you get air pockets; and the car starts to overheat. All over a part that cost about $20 and should be tested and/or replaced regularly..............

[clickman]

Originally Posted by JFP in PA

The system has a vent line that runs under the car, when the system pressure exceeds the cap pressure rating (which drops from its original 18.2 PSIG over time and with use), coolant goes out the vent and onto the ground. Now that there is air space in the surge tank, air starts circulating in the system, and you get air pockets; and the car starts to overheat. All over a part that cost about $20 and should be tested and/or replaced regularly..............

Replace how regularly?

[JFP in PA]

Originally Posted by clickman

Replace how regularly?

We pressure test them every time a car comes into the shop; if they don't hold until 18.2 PSIG, they go in the trash. Never tried to develop an "average life expectancy", as it seems to be all over the map. If you can't pressure test, I would replace it at least every two years.

[jotoole]

Originally Posted by JFP in PA

We pressure test them every time a car comes into the shop; if they don't hold until 18.2 PSIG, they go in the trash. Never tried to develop an "average life expectancy", as it seems to be all over the map. If you can't pressure test, I would replace it at least every two years.

That seems to be my luck with the caps, have always had that condensation so I've ordered yet another "04" cap.

[Idaho Red Rocket 3]

2000 Boxster S 82,000 miles with original cap and no problems.