| Author |
Message |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1547
Registered: 11-2002
| | Posted on Saturday, May 24, 2003 - 12:01 pm: | |
Pete,
The colors indicate the type of oil the o-ring is compatible with, Green & Blue are universal (pag, ester, mineral)...black is only compatible with mineral oil.
For 134a Green or Blue..no black. For R12 all 3 are ok.
I suggested green in case someday his system is changed to 134a he won't need to worry about those particular seals again. |
pete gorrell (Rufus)
New member
Username: Rufus
Post Number: 40
Registered: 2-2002
| | Posted on Saturday, May 24, 2003 - 11:44 am: | |
Hey, JRV...
Engine's out, so I'm switching to R134A.. got the package of O-rings for the change, about 150 or so various sizes, multiple colours of each size, presumed they were all OK for new refrigerant. Now your 'green is OK' comment makes me realize how dumb it is to make any assumptions... Are these things colour-coded? What are the non-green ones for?
Thanks for your help... A/C is new to me! |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1528
Registered: 11-2002
| | Posted on Thursday, May 22, 2003 - 6:54 pm: | |
Probably helpful to explain how freon works also.
Freon doesn't cool anything off per se...although when it's transformed from liquid to gas it does get extremly cold, the way it works is by drawing the heat out of the air that passes across the evaporator.
As forced air is blown across the evaporator the heat in the air is drawn into the froen inside the evaporator and carried away to the compressor where the heated gas is recompressed into liquid, this heated liquid is then sent to the condensor where it is cooled off and sent back to the expansion valve to change back into heat absorbing gas. The high or hot side has to be cooled to keep the pressure within a range that it can efficiently be handled by the components and draw off more heat once converted back to gas.
At least this is how it's been explained to me.
|
Tom Bakowsky (Tbakowsky)
Member
Username: Tbakowsky
Post Number: 401
Registered: 9-2002
| | Posted on Thursday, May 22, 2003 - 6:39 pm: | |
M-Benz does the samething. |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1527
Registered: 11-2002
| | Posted on Thursday, May 22, 2003 - 6:35 pm: | |
Jeff/Paul,
never investigated this to any serious degree, however it was my understanding that the fuel cooled the high side line as it passed thru the tank to help the effieciency of the AC system. The high side of an AC system gets very hot, hot enough to burn a finger or two when poking around looking for problems. So hot in fact the AC condensor has to have a fan blowing across it to disapate the heat generated. It was my understanding that Ferrari did this to increase effieciency to a degree never before dreamed of in a Ferrari. Normaly, freon isn't used for cooling until it goes from it's liquid state to it;s gaseous state as it passes thru the expansion valve.
Of course I may be mistaken. |
Jeff Green (Carguy)
Member
Username: Carguy
Post Number: 300
Registered: 10-2002
| | Posted on Thursday, May 22, 2003 - 6:24 pm: | |
Paul...it seems that the AC not only cools down the inside cabin temps, but also the fuel temps. At least this is what I'm told. This nice bit of info. is not shown in the work shop manual or parts manual. It was a pleasant surprise for me as the coolant just "blew out" into my face as I was under the car removing hoses and fittings! Very Nice! |
Paul Hill (348paul)
Member
Username: 348paul
Post Number: 253
Registered: 12-2002
| | Posted on Thursday, May 22, 2003 - 6:15 pm: | |
Jeff/JRV
Why does the AC flow through the tank??? Scratching my head here but can think for the life of me why!!
Paul
|
Jeff Green (Carguy)
Member
Username: Carguy
Post Number: 299
Registered: 10-2002
| | Posted on Thursday, May 22, 2003 - 5:55 pm: | |
I will get the tank physically installed tonight, and do the hook-ups tomorrow. Took a look at your profile.....MAN-OH-MAN! That is a great pic! Even my two nosey cats who are always looking over my shoulder, were impressed! That would make a cool poster for my measily little shop! |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1526
Registered: 11-2002
| | Posted on Thursday, May 22, 2003 - 5:44 pm: | |
Yes, they're a common problem......it would really depress DRstrangelove (again) if he knew how often those .50 cents worth of parts resulted in $100's of dollars worth of lost freon.
;-) |
Jeff Green (Carguy)
Member
Username: Carguy
Post Number: 298
Registered: 10-2002
| | Posted on Thursday, May 22, 2003 - 5:39 pm: | |
Sounds like a good idea-since so cheap. Do the valves become a leak source over time? |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1525
Registered: 11-2002
| | Posted on Thursday, May 22, 2003 - 5:35 pm: | |
Jeff,
while you're picking up that dollars worth of o-rings do yourself a BIG favor and splurge another .50 cents on new schraeder valves and swap out with the old ones while the AC system is empty.. |
Jeff Green (Carguy)
Member
Username: Carguy
Post Number: 297
Registered: 10-2002
| | Posted on Thursday, May 22, 2003 - 5:29 pm: | |
Yeah that was fast.....but not as fast as your response to my question!! Thanks JRV...
The guy who fixed the tank asked around as to "why is the A.C. routed through the tank?" And his sources said that it's to cool down the fuel. So I was wrong when I thought that the fuel was the coolant, it's actually the "warmer"! Those Italians...you gotta love 'em! |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1523
Registered: 11-2002
| | Posted on Thursday, May 22, 2003 - 5:24 pm: | |
Just use the correct sizes (metric) found at any parts store in green. Green is compatible with R12 or R134a.
The sizes are the same as used on many Japanese cars. Both diameter and cross section (thickness).
Congrats...that was fast. |
Jeff Green (Carguy)
Member
Username: Carguy
Post Number: 296
Registered: 10-2002
| | Posted on Thursday, May 22, 2003 - 5:17 pm: | |
My gas tank has been repaired, two holes fixed, two new vapor hose nipples (I tore the old ones off getting the hoses off!), and the sending unit spring cleaned, bead blasted and coated. It's as good as new....cost was $175. Now since the A.C. flows through the tank, I need to replace the O-Rings at the fittings. Can these be just ordinary O-Rings or must they be some special material? Not sure what refrigerant was in the system, would this make a difference? |