Car over heating

[Paulsingh]

Hey guys.

Still trying my car back on the road.

Passenger radiator was damaged, I've replaced it now and topped on coolant. Let the car run to correct temp but it carried on heating up. I was hoping it was an air lock but can't seem to get anymore out. Is there another bleed valve by the rads etc? Both rads are cold at 90deg?

Appreciate ur help on this!

Paul

[JFP in PA]

First, you need to be very careful about this; hot spots and over heating can be death to these engines. These cars should be filled with coolant using a vacuum system that eliminates any chances of air entrapment in the system. The system sells for about $100 (US), and fits any car. As the radiators are for the most part lower than the engine, replacing parts up front has trapped air in the system. The best way to get it out is using vacuum pulled on the fill opening in the rear boot. Most independent Porsche shops, and for that matter most well equipped shops, have vacuum fill equipment that can do the trick for you.



There is also a bleeder valve in the rear boot (it is the only one on the system) that can get out relatively small amounts of air, but using it takes time and is not always completely successful in getting all the air out. There are several write ups on how to use this valve.



Makes some phone calls and find out who has the vacuum system; with it you will be air free in about 5 min.

[thstone]

Go to the Pelican Parts site, find the Tech Articles section, and follow the instructions for bleeding the coolant system under Coolant Replacement.

http://www.pelicanparts.com/techarticles/Boxster_Tech/29-WATER-Flush/29-WATER-Flush.htm

Or better yet, buy Wayne's book, "101 Projects for Your Boxster" and you'll have 90% of the answers for almost any job right at your fingertips.

[jmatta]

I replaced my coolant a year and a half ago when I installed the LN low temp t-stat. Admittedly, I didn't drain the front radiators; only opened up the system underneath, but proceeded with the manual bleeding system with great success. Drove the car around for two days with the valve open and added coolant in the AM, until it was no longer required. Regrettably, I should have also replaced the water pump at the same time, after reading all the possible failures with an older pump (mine is original, 9 years, 19k miles).

I see another coolant change coming in spring when I do the pump, which I question...can I save and reuse my present 1.5 year old coolant?

As the original poster questioned, hot spots can be deadly to these engines so heed JFP's advice.

[JFP in PA]

Saving and reusing the coolant is totally dependant upon your ability to capture it cleanly and return it to the system with no entrained contaminants. In most DIY situations, not enough time or effort is made to assure that happens, so a fresh refill is in order. If you do make the effort, you will be fine.

[jmatta]

Thanks, JFP...I would anticipate capturing the coolant in a new, clean container since I purchased the good stuff from Pelican. I'd order some back up, anyway, just to be safe.