Hello All - I need some diagnostic guidelines regarding my AC.
(The system was running the original R12 refrigerant.)
It worked all last year and then quit this summer. The switch
engages "something" (I hear a click) but the rotor does not spin,
and the high pitch whine from the compressor is not audible.
Is this related to low R12 pressure ? clutch wear ? etc... ?
I do not have a manifold pressure gage - so I don't know the
status in the system

So - I have seen R12 sold on ebay - is this genuine and legit ???

If I transform the system to 1394, I would have to take it in to
a shop to remove the R12 completely - fine - are there any
special tools required: I have seen kits available to do the
transformation - are there any recommendations ?

THANKS MUCH !

 

Do this first:

Turn key to ON(II). Turn A/C button OFF and cabin blower ON to highest speed.

Start engine.

Raise hood.

Look at the condenser fan and the armature plate at the front of the compressor pulley. The condenser fan and compressor armature plate should NOT be spinning.

Turn A/C button on.

Are both the condenser fan and compressor armature plate now spinning?

 

Thanks very much for your suggestions - I will try this tomorrow morning,
since it is late and rainy here.

 

Muellersfan -

I did the check this morning :

With the engine cold, AC switch in OFF position
the condenser fan and the armature are stationary.

With the AC switch ON both the condenser fan and the armature
plate rotate.

I will try this again with the engine HOT

Does this indicate that the 25+year R12 is low or depleted and
everything else is fine ???

Thanks Much for your time and helpful advice

 

If the results repeat with the engine hot, it's time to hook up a manifold gauge set (rather than station shown in the first diagram).

 

Yes - The results were a repeat with the engine hot -
Looks like I will have to get a MPG - I'll look for one.
Is e-bay an option - any suggestions ?

Thanks Much!

 

eBay is a good place to start for used pressure gauges. Get one that has adapters for both R12 and R134a if you possibly plan to do the conversion.

 

Thanks Much - it appears also that R12 is "available" on ebay -
I would actually like to keep the system as is -
just wondering about the process of a recharge with R12 ?

 

Same as recharge with R134a --> by weight of refrigerant (and you also may need to add oil).

Wait until you get the diagnosis provided by the manifold gauge test. The finding may compel you to change course.

 

Thanks Muellersfan - I'll order one tomorrow morning and let you know - appreciate the guidance !

 

Have you considered R134a conversion?

 

Freedo - Thanks - yes I am looking into it. I'm looking at pressure gages
and the ratings for them are all over the place, so I will go to advance auto and
see if they have a rental. Following this I will decide on the 134 - they
say cooling is not great compared with R12 but I have been in some
recent model cars and didn't notice much difference - but my unit is a 1992 !

 

There is also an R12a conversion. It's legal in Canada, but in the US the EPA hates it. That said there are zero cases in Canada of R12a causing any sort of problem, so there's that. It's a drop-in replacement for R12, with lower head pressures, even. Excellent cooling. No ozone layer depletion problems. Trade names include RED TEK, Duracool ... there are others.

 

Thanks for the info - do you have a link ?
I am looking at keeping the system as is,
and avoid the hassle of conversion. Honda
used to sell a conversion kit - but it is no
longer available.

 

Bit of reading:

Duracool® Technical Information - FAQ'S
http://www.968forums.com/topic/905-m...-refrigerants/

Second link is consistent with my experience.

 

deschlong : Thanks much - I'm still reading through the material - it is very useful.
Question : my a/c has never been abused - just sat there working fine, and I believe
all I need is just a recharge. What I would ideally like to do is just leave the system
as is, and just put in the new charge. I probably do not have any leaks - keeping in
mind that I have never recharged the original system for the last 25+ years and it
worked fine . . .

Please correct me if I am mistaken - I can get "external" adapters which fit to the R12
hardware on the a/c and just recharge the system ? Is there a kit that does this that
has the pressure gauge built in so I can do it safely. I would do it outdoors for sure.
(The e-bay link provided in the forum is now gone)


THANKS MUCH !

 

If you're interested in adding a cabin filter, now's the time to do it. DIY for it is here: https://docs.google.com/document/d/1...VZRaPw/preview

Get yourself some R12 to R134a adapters: ... just make sure that the sizes are CORRECT! Our old 90s Hondas use a funny either low or high side size (I forget which). Measure this. Also, get a half-decent brand, not Made in China noname crap.

 

Thanks Much - Just checking online, there appears to be a very healthy debate
about HC (r12a) refrigerants in regard to safety. I'm still debating where to go.
I still think that my best option is to get R12 and do a simple recharge. But how ????

 

I attribute that to fear mongering by DuPont and the fluorocarbon manufacturers. No restrictions here in Canada and the news isn't full of horror stories about gruesome injuries due to mobile a/c filled with hydrocarbons exploding. Not even one! Just make sure your whole system is all in proper working order. But you can always convert to R134a and have it suck. :/