Porsche 911 Carrera Water overheating?

Hey im new to all this so please be patient I have a 51 reg 911 Carrera triptronic S And after driving for about 45mins the water temp levels go sky high. The warning lights come on After the ignition is turned off (take key out lock doors etc) The fan stays on for about 30mins or so Anyone have any ideas on what this could be? Ive not noticed any water leaks or anything of the sort. water is topped up Thankyou for all your help in advance :thumb:

have you checked your coolant levels ? (note have a look in the manual for exact info on how to do this)

hey Sandeep many thanks for the reply I did not get a owners manual with is from the last owner All coolant levels that i have got checked seemed fine BUT ive noticed the hydrolics Oil level dropping alot?

Something sounds very sick. Are both the coolant fans working at the front? Is the coolant level normal? No leaks from the water pump? Is it losing coolant? When you say hydraulic oil, do you mean motor oil? If it is, is it mixing with the coolant? Could be a head gasket, oil seperator, early signs of bore failure although by now it would have been evident. Take it to a local indy to have it looked at.

Hey there dont seem to be any leaks anywhere its been parked up for a week and there are no water or oil patches on the floor? the hydraulics oil is sep from the main motor oil doesnt take much to fill someone did say that the new radiator that was put upfront has not been bled properly? could this be it Is there a speical way to bleeds these if so how? many thanks

If it is the hydraulic oil that sounds like the power steering pump reservoir. There could be an airlock in the cooling system and there is a Porsche way of bleeding it. Do a search on Renntech forum and the procedure is listed there.

can a airlock happen randomly? was ok before soorry im 24 and this is my 1st porsche dont really no alot about it Many thanks for all the help

Airlocks don't happen randomly unless the cooling system was disturbed or something is leaking out letting air in. Given you are 24 and not too sure what is going on, for your piece of mind, take it to a reputable independent for them to have a look. There are a lot about who wouldn't take you for a ride and will at the very least tell you if the problem is serious or not. I'm sure you have done your research on 996s before you bought yours and you will know you want to have any overheating problem sorted pronto or it could be big, big bills. I have an early 996 myself and I love it and would do a lot of the work myself but any problem arising I would always sort quickly as the thing can escalate. 996s are cheap at the moment but it was a £60k car with possible bills to match. It is much cheaper to run and a lot more reliable than other GTs/supercars but it still wasn't a cheap car new. They still need TLC to keep them sweet. The Renntech and Porsche Club GB forums are also very good for technical advice.

MAny thanks for your response. I was looking throught the service book and it showed that the radiator had been replaced i checked all the coolant levels. I turned by internal fan on low 3 bars (cold air) and took it out for a long drive last night it was quite quick to get between 80/90C and remained steady no error lights etc Just wondering how long is the fan at the rear ment to stay on After turning the car of is it ment to stay on at all :dont know: ? Thanks a million for all your help and support

There are 2 fans at the front and one in the engine compartment. The description below is taken from the workshop manual: Radiator fans: Stage 1 is switched on when the coolant temperature is >100 °C or the aircon is on, the intake air temperature is >8 °C and terminal 15 is switched on. Stage 2 is switched on when the coolant temperature is >105 °C or the refrigerant pressure is >16 bar. Engine compartment fan: The engine compartment fan is switched on when the engine compartment temperature is >80 °C or the coolant temperature is >102 °C. After-running of engine compartment fan If the ignition is switched off and the engine compartment temperature is more than 60 °C, the DME control module remains in readiness for another 20 minutes. During this time, the engine compartment temperature is retrieved every 10 seconds. If the engine compartment temperature is >85 °C, the engine compartment fan is switched on for 20 seconds. If the engine compartment temperature is still >85 °C after this time, the fan remains on for a further 30 seconds. To be honest, my 996 is used daily in all conditions and in traffic the temperature can climb to about 95 (just right of the 0 of 80 on the dial). Even then I have never had the engine fan click on or the radiator fans engage high speed. At normal running temperature, if the aircon is on, both the fans at the front will come on. Put your hand under each side of the front bumper and you will feel air blowing. When the fans click onto high speed(stage2) you can hear them miles away!

Advice: Check your coolant level after a good run (hot engine) *with the engine still ticking over* I think you may find it has vacuumed down by a few inches. Don't panic, carefully remove expansion cap and fill to level with enginge still running.

JC - NEVER EVER unscrew the cap on a hot 911 engine. You may not be seeing a leak but sometimes the rads/pipe unions start to weep/mist coolant. Its a slow process over a period of time. In severe cases you will start to smell a sweet odour(that's the anti-freeze/water mix evaporating) and maybe some steam. One other common culprit for small leaks is the plastic pipe that runs o/side to near/side of the engine. It rubs against the rear undertray. I assisted a guy in Russia on here with this exact same problem(he saw no water on the floor but the leak was so small it hardly dumped any coolant) If you remove the expansion tank cap do this only when the car is STONE COLD. Then start up the engine. When it's still cold let the car idle until the temp guage just starts to move(DO NOT LET IT WARM_UP). Top up if required then immediately put the cap back on. This coolant circulation/top-up process when the car is COLD often pushes out any airlocks.....you may need to repeat this simple process over a few days/week to purge any airlocks. Just make sure you are not just adding water but also the correct anti-freeze/coolant mix? If the level still drops after the cooling system has been checked then you probably have an engine oil/water mix problem(check your oil filler cap) for a creamy white gunge. So do the airlock purge/top-up procedure I outlined above than get the coolant system checked from back to front if your coolant level still drops.

just an update it stil overheats but i have put in a manual switch to turn the fans on at the front when this happens things cool down again any ideas?

You need to get this into a good independent Porsche garage for a check over as this sort of overheating is a potential symptom of a much more serious failure. Phil

what else could happen anyone know of a decent place to get checked? im based in luton does anyone know a good place near by