I've got a 1991 crx si. It used to have AC but all the freon is gone due to a leak. How and where do I tell if I have a leak? Do most leaks come from the hoses? Should I just replace a hose, or is it more complicated than that?

 

you can buy a flourescent black light dye that goes in the system and with a black light it will glow where you are leaking

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Crx Jimmy &raquo;</TD></TR><TR><TD CLASS="quote">you can buy a flourescent black light dye that goes in the system and with a black light it will glow where you are leaking</TD></TR></TABLE>

yea I tried to do this with my oil. It didn't turn out so great. I'm sure it would work better in ur ac system though.

 

Appreciated. Thanks.

 

if it's a big leak then maybe you'll see oil on the lines. I'd fill the system with 300 psi nitrogen. at this pressure the leak should be obvious. you have a leak if you charge it with 300 psig n2, come back later and the gage reads less than 300 psig or if you remove the non-condensables and it doesn't hold vacuum.
don't replace anything until you have proof that it failed. could be a 50 cent part like a schrader valve in the access port that still leaks after you bought a new hose.

if you can't hear it there's always soap bubbles and as a last resort an electronic leak detector.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by eda6 &raquo;</TD></TR><TR><TD CLASS="quote">if it's a big leak then maybe you'll see oil on the lines. I'd fill the system with 300 psi nitrogen. at this pressure the leak should be obvious. you have a leak if you charge it with 300 psig n2, come back later and the gage reads less than 300 psig or if you remove the non-condensables and it doesn't hold vacuum.
don't replace anything until you have proof that it failed. could be a 50 cent part like a schrader valve in the access port that still leaks after you bought a new hose.

if you can't hear it there's always soap bubbles and as a last resort an electronic leak detector.</TD></TR></TABLE>

Where can I buy the nitrogen?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Crx Jimmy &raquo;</TD></TR><TR><TD CLASS="quote">you can buy a flourescent black light dye that goes in the system and with a black light it will glow where you are leaking.</TD></TR></TABLE>

Where can I buy a flourescent black light dye?


By the way, this information is REALLY helpful guys

Looks like I won't have to go to a shop anymore.

 

I think that 300 psi of nitrogen is a little much, don't you? I would try 50 psi at the most. Also, most of the times it is the O-rings that go bad due to age. There are probably about 10 O-rings under the hood and you have to take the front bumper off to get to the ones near the condenser. Also if the system has been open for a long time you really need to evacuate it (pull a vacuum) to draw out moisture. A new drier is also recommended (in front driver's side under hood to right of compressor). The lines usually don't go bad it is almost always the O-rings.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr. Famadico &raquo;</TD></TR><TR><TD CLASS="quote">

Where can I buy the nitrogen?
Where can I buy a flourescent black light dye?

</TD></TR></TABLE>

a refrigeration parts house has everything you need. The bottle costs $75 and the n2 costs $10.
yellowjacket makes a kit that includes a blacklight and dye.
my advice-go there and wait for a tech to pull up, ask him to fill your system with n2 and offer to buy him lunch. buying the guy lunch has to be cheaper than $85.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sbarmann &raquo;</TD></TR><TR><TD CLASS="quote">I think that 300 psi of nitrogen is a little much, don't you? I would try 50 psi at the most.</TD></TR></TABLE>

i don't think that 300 psig n2 is that much. before a coil leaves the factory they're filled with 200-400 psi n2 to make sure there's no leaks. during mechanical cooling the head pressure is at least 150 psig and when the system is off static pressure can be greater than 100 psig depending on ambient temp. why stop at 50 psig?

 

The leak in your A/C system could be any where your best bet is if you havent retro fitted the system from R-12 to R-134a yet is to take it to someone professional and have them retro fit it and find the leak and fix it. The best way to detect the leak is to inject dye and recharge the system with freon to its proper amount run the A/C system sometimes you find the leak right away sometimes it may take a week or two for the slow leak to show itself.