air cooling

[fgasca]

Hi everyone,

I have a small???? problem. Just discovered that the plastic piece just behind/top the fun has a 2 inches hole on it... I don´t now why. Does anyone know the reason for that or how it could have happened? Potential damage to the engine? No warning lights oil pressure or temperature issues.


Thank you

Fernando

 

[Dave Wilkinson]

Fernando,

Your picture is very small so I can't see mucyh detail but from your explanation and the little bit I can see it looks like the rubber piece between the fan and the blower plenum. It's failure won't have any major impact on performance but probably best to replace ASAP.

It's not uncommon - my own had the same problem a couple of years ago. The part seems to get stressed by the vibration and just cracks - and I'm sure age plays it's part too. The part isn't very expensive and it's pretty easy to fit.

Regards

Dave

 

[fgasca]

Hi Dave,

Thank you for your quick answer. I have spent all the sunday driving and when I noticed that I felt very depressed! Hopefully it looks not very important.

Another question, and this one is very silly, I´m having problems reading the oil gauge, I have raden it in other cars I had previously but in the 964 its like it is more difficult, is this normal? May be I´m becoming a little bit paranoid with the car! ICould exist any possible link between the oil level and this problem with the cooling system?

Regards

 

[Dave Wilkinson]

Fernando,

Fear not - you are not alone with the oil level issue!!! To understand the oil level - whether it be dipstick OR gauge - you need to understand a little about the oil system itself. Because the 964 uses a dry sump system it is unlike virtually any other car you have seen. The oil is held in the tank behind the right rear wheel arch and is supplied to the engine as required. As the oil is circulated and heated by the engine it gets retuirned to the tank via a thermostat which, once actiavted, will route the returning oil via the oil coolr in the front right wing. Only when the oil returns to the tank does it settle in the part where the level is capable of being measured.

While you are driving there is obviously a constant draw on the oil supply and the level is meaningless. Only when the engine is idling with the thermostat open can the level measured. It goes without saying that the car needs to be on level ground.

If the oil level is fairly high you will find that the gauge will move off the red while you're driving but it doesn't really mean much. Only when you stop, leave the engine to idle for at least a minute or two and the level on the gauge should gradually creep up to it's meaningful level. I find the stop at a traffic light to be a good opportunity to check it.

Just try to resist the tempation to check the dipstick in the garage first thing in the morning. It's the stuff that heart attacks are made of!!!

Regards

Dave

 

[fgasca]

David,

Thanks again for your clear explanation. Very useful and relaxing.

 

[fgasca]

Good morning everyone,

And what would be the best way to know the engine temperature? I mean how can I know if its becoming too hot? Would the oil temeperature be a good indicator of the engine temperature?

Thanks

 

[Dave Wilkinson]

Fernando,

The oil temperature is the only data you have available to you. You will find that as the car (i.e. engine) warms up the oil temperature indiactor will gradually rise to the second mark on the dial (approx 8 o'clock) and then, usually quite suddenly will fall back to somewhere between the first and second mark. That moment of the drop coincides with the opening of the oil thermostat and from that point onwards the oil level gauge becomes meaningful.

Bear in mind that oil expands with heat so the hotter the oil gets the more of it there is. This is why it's so important NOT to fill right up to the full mark if the oil is only just warm enough to open the thermostat. If it subsequently gets significantly hotter you run the risk of overfill consequences.

Hope that answers your question.

Regards

Dave

 

[fgasca]

Hi Dave,

Abolutely. Thank you very much for the explanation.

 

[grandad]

I am currently driving my fourth Porsche 911 and I am still learning. Thanks for the explaination. This will help many in the future when doing an oil change or just topping up.