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Discussion Starter #1
HI,

Summer in TX is approaching so I did some AC work for a friend on an 97 Acura which has a small leak but usually needs a can of R134a.

I also decided to check the S500...

This time around, I noticed and rented a real nice master cool R134a 2-way manifold gauge set from AutoZone for FREE ($99 deposit/return). The kit has EZ lock fittings and a nice refrigerant can valve. They also have a 2CFM rotary vane vacuum punp for rent which I didn't need.

I picked up a case (12-12oz. cans) of Johnsens R134a from SAM's for $36. Come's out to $3.04/can. Pep Boys sells it for $9-14/can...

So, here's some pix with hi side (red), low side (blue), and can (yellow) hookups. Based on ambient temps, 85F and looking at the temp chart, I was low about 1.5-12oz cans. I ended up using a little over one can and my AC improved quite noticably for ~$5 :) The AC has never been serviced or checked in over 10yrs...:confused:
 

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HI,

Summer in TX is approaching so I did some AC work for a friend on an 97 Acura which has a small leak but usually needs a can of R134a.

I also decided to check the S500...

This time around, I noticed and rented a real nice master cool R134a 2-way manifold gauge set from AutoZone for FREE ($99 deposit/return). The kit has EZ lock fittings and a nice refrigerant can valve. They also have a 2CFM rotary vane vacuum punp for rent which I didn't need.

I picked up a case (12-12oz. cans) of Johnsens R134a from SAM's for $36. Come's out to $3.04/can. Pep Boys sells it for $9-14/can...

So, here's some pix with hi side (red), low side (blue), and can (yellow) hookups. Based on ambient temps, 85F and looking at the temp chart, I was low about 1.5-12oz cans. I ended up using a little over one can and my AC improved quite noticably for ~$5 :) The AC has never been serviced or checked in over 10yrs...:confused:
Hey Moss500,
Thanks a bunch for posting these pictures!

I'm going to try recharging my AC with your guidance, tomorrow. I just replaced the AC control module in the dash and the blower regulator under the hood. Everything is now working except blowing hot air.

If the R-134A charge works you just helped me save $500 bucks, minimum.

Awesome!
 

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HI,

Summer in TX is approaching so I did some AC work for a friend on an 97 Acura which has a small leak but usually needs a can of R134a.

I also decided to check the S500...

This time around, I noticed and rented a real nice master cool R134a 2-way manifold gauge set from AutoZone for FREE ($99 deposit/return). The kit has EZ lock fittings and a nice refrigerant can valve. They also have a 2CFM rotary vane vacuum punp for rent which I didn't need.

I picked up a case (12-12oz. cans) of Johnsens R134a from SAM's for $36. Come's out to $3.04/can. Pep Boys sells it for $9-14/can...

So, here's some pix with hi side (red), low side (blue), and can (yellow) hookups. Based on ambient temps, 85F and looking at the temp chart, I was low about 1.5-12oz cans. I ended up using a little over one can and my AC improved quite noticably for ~$5 :) The AC has never been serviced or checked in over 10yrs...:confused:
Hi MOSS500 and Others...
I tried to charge my A/C. I bought a can of R134A with integrated pressure guage and plugged it into the low pressure nozzle after running the car with AC on High for 3-4 minutes. I did not plug in anything to the high pressure (larger) nozzle in the front of the car by the radiator.

When I pressed the button on the R134A can.. the pressure guage simply dropped slowly from about 35lbs to Zero.

Any suggestions?

Thanks All - JimK in Seattle
 

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If your system was empty it means that you still need more 134!! 1 can ain't gonna make it!!

Smokie
 

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If your system was empty it means that you still need more 134!! 1 can ain't gonna make it!!

Smokie
Yep...

the user manual of your car will have the specs for your car's capacity.
 

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Discussion Starter #7
If your topping off, something doesn't seem right. Your low side should be anywhere from 25-40psi depending on ambient temps. Sounds like your AC system is completely empty as others have speculated. If thats the case, you need to pull and hold a vacuum of 25" or better for an hour otherwise you have unacceptable leaks that need to be addressed....
 

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Thank you for the information OP

I just emptied out a 22 oz. giant size "arctic freeze" of 134a+ can into a 1993 W140 500sel this morning and the a/c is once again "blowing sharpy cold"!

Many thanks to your very helpful diy.
 
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