Beretta.net

Okay, this should work to retrofit my 89 GTU's AC into 134a, right?

http://www.autozone.com/autozone/access ... 42674_0_0_

Thanks

Also, how much 134a should I need?

Yes that will work. Its what i have on my 90 GTZ. I checked all data and it says 44oz of refrigerant for an 89 2.8

You will need more than just the fittings. You need to add some 6-8 oz Pag oil as well, since the system has mineral oil in it.
R134 will not circulate the mineral oil.
As for the amount of 134, it is supposed to be 80% of R12 amount to avoid over pressurizing the system.
Do an internet search for more information.
here is a link
http://idqusa.com/faqs/?faq=11

I still have the R-12 oil in my system, and it works fine. Yes you're supose to flush the system and add pag oil but its not needed. Mine blows 44 degrees this way.

Yes but if you added R134 with the over the shelf cans most come with some oil in it so you could have inadvertently added oil to the system.

I need to re-charge mine for Bfest.

"I still have the R-12 oil in my system, and it works fine. Yes you're supose to flush the system and add pag oil but its not needed. Mine blows 44 degrees this way."

I'm glad it worked for you, I hope it continues to work for you.
But no, you are not supposed to flush the system. Leaving the mineral oil in protects the o rings which are
not compatible with R134. If you flush the system you will need to change all the o rings.
And your 44 degree statement. You may have had a 44 degree output on a given day but the output temperature is dependent on the ambient temperature. Look for a twenty degree drop to tell you the system is working fine and is fully charged.
The manufacturer of the r134a says to add pag oil. I'm sure they are not just trying to sell oil.
I suggest anyone retrofitting should follow an informed manufacturer opinion and spend a few bucks
and add the right oil otherwise you risk screwing up your compressor which costs a lot more.

jskiguy wrote:"I still have the R-12 oil in my system, and it works fine. Yes you're supose to flush the system and add pag oil but its not needed. Mine blows 44 degrees this way."

I'm glad it worked for you, I hope it continues to work for you.
But no, you are not supposed to flush the system. Leaving the mineral oil in protects the o rings which are
not compatible with R134. If you flush the system you will need to change all the o rings.
And your 44 degree statement. You may have had a 44 degree output on a given day but the output temperature is dependent on the ambient temperature. Look for a twenty degree drop to tell you the system is working fine and is fully charged.
The manufacturer of the r134a says to add pag oil. I'm sure they are not just trying to sell oil.
I suggest anyone retrofitting should follow an informed manufacturer opinion and spend a few bucks
and add the right oil otherwise you risk screwing up your compressor which costs a lot more.

So you're saying that if its 90 degrees out the A/C should blow 70 degrees? I'm confused by your statement. Yes the output temp does depend on the heat and humidity. Even on Hot days my A/C blow no higher than 48-50 degrees. I've just added 134a to my 90 GTZ, a 91 Bonneville and a 91 corrola, all still fine. And when manufactures say all the o-rings and acumulaters ect need to be replace, it all about the money. If your R-12 ac componets are in good working order, Adding 134a will not hurt the system, But do not mix R-12 with 134A. Make sure you pull a vacuum to it to get all the old R-12 out.

Well, I thought about it and I'll have it leak tested before I charge it since its completely empty to my knowledge.

jskiguy wrote:"I still have the R-12 oil in my system, and it works fine. Yes you're supose to flush the system and add pag oil but its not needed. Mine blows 44 degrees this way."

I'm glad it worked for you, I hope it continues to work for you.
But no, you are not supposed to flush the system. Leaving the mineral oil in protects the o rings which are
not compatible with R134. If you flush the system you will need to change all the o rings.
And your 44 degree statement. You may have had a 44 degree output on a given day but the output temperature is dependent on the ambient temperature. Look for a twenty degree drop to tell you the system is working fine and is fully charged.
The manufacturer of the r134a says to add pag oil. I'm sure they are not just trying to sell oil.
I suggest anyone retrofitting should follow an informed manufacturer opinion and spend a few bucks
and add the right oil otherwise you risk screwing up your compressor which costs a lot more.

The manufacturer DOES say that you're supposed to flush it AND replace all the seals THEN re-fill it with PAG oil. Otherwise you'll have waay too much oil in your system if you just add an additional 6 oz..

However, even though I do these retrofits often in the dealership, I still don't flush it. Since it's not really necessary. Put on the new fittings, buy some (2oz or less) universal oil (oil that works with both pag and mineral oil-I get it form napa-) and then recharge it. You can buy an entire retrofit kit from napa that comes with fittings, oil, and r1234a o-rings for like $50 if you're that paranoid.