Rich Osborne

My wife is bugging to fix the A/C in my 1970 911S Targa before we head out to Boise in July. I would like to read up on A/C. Are there any sites I can research for air conditioning on my year car? I was told that the compressor on the engine is a Tecumseh unit. Does anyone know whether this is a factory option or a dealer option? What is the unit under the front compartment - is it the refrigeration unit where refrigerant gets loaded?

HarryD

Hi Rich,

If you do a search, you should find some previous postings on this topic.

I am assuming your 70 is like my 73. In the rear is the compressor and condensor. The evaporator is in the front of car with the expansion valve and AC Blower. There are two Looooong lines to connect the two parts. Freon in in all of these parts.

My AC is disabled (the compressor is frozen and removed along with the condensor). In my previous web searches, it appears to cost around $1,500 to $2,000 to make functional. For me, that was too much. Others have updated the compressor and had some sucess making some cooler (not frigid) air.

I am sure that the other experts can help you more than me but I would be interested in hearing about your progress as resoting the AC is a long term goal for me also.

procooler

Hi Rich,

The compressor which is in the engine compartment is were you normally load the refrigerant. the compartment in the front, houses the evaporator and txv (thermal expansion valve)which meters the amount of freon entering the evaporator. the receiver/drier which normally is in the left wheel well on factory systems stores liquid freon after it exits the condensor (which should be in the deck lid). the sequence is like this: The refrigerant vapor is compressed which heats it up, it then goes to the condensor where it is cooled by air passing through the condensor, this cooling causes it to become a liquid which is stored in the receiver, then it goes to the expansion valve hopefully still a liquid (rarely is). the expansion valve is a restiction in the system. high pressure on the discharge side and low pressure on the suction side (or return to the compressor). as the liquid refrigerant goes from high pressure to low pressure inside the evaporator it becomes cold and is able to absorb heat from the car as hot air is passed over the evaporator. it then goes back to the compressor and starts all over again. whew! thats the short version.

now that your totally confused, i hope that helps

ron m
<a href="http://www.procooler.com" target="_blank">www.procooler.com</a>
inspired ideas for a/c systems
rennlist member

HarryD

Rich,

I was over at Pelican Parts and found this. It may help you out.

<a href="http://www.pelicanparts.com/techarticles/mult_AC_faq.htm/Mult_AC_faq.htm" target="_blank">Air Conditioning in 911s</a>

JackOlsen

Here's another good place to look.:

<a href="http://www.griffiths.com/porsac911.htm" target="_blank">http://www.griffiths.com/porsac911.htm</A>

Best path is to update to the rotary compressor and replace all those designed-to-leak hoses.