S14 RB25 A/C Issues

[Sileighty_85]

Well this is more of a confirmation thread for me, so ppl that have knowledge on A/C systems or had this issue and fixed it chime in.

Its a RB25, 98 S14, A/C worked awesome before the swap, No issues.

New Parts: Got a brand new A/C condenser and band New Nissan OEM Filter drier WITH Pressure Switch, Brand new custom lines made by an A/C shop using all new hoses.

Whats Going on and Info:
What I think is going on is I think the bearings are bad in the A/C compressor cuz when its at idle it works fine but makes a squeaky grinding noise when its engaged. When driving it kicks on and off, stays off longer than on.

I thought maybe the Filter Drier was getting heat soaked and messing with the pressure sensor, so kinda ghetto shielded it
(Yes its fucking ghetto, gonna make a heat shield later)
http://i73.photobucket.com/albums/i235/Neil_85/Miyukis%20Silvia/DSCN5394.jpg
I even went as far as taking off the hood and driving around, Still does it.
The firewall small HP line is still warm, but the big LP line is fairly cool even when around the turbo.

Now the HP line coming right out of compressor, Hotter than the damn exhaust manifold. I know the freons gonna be hot when compressed but not this hot.

I even went ahead and shielded the low pressure lines thinking they are getting heat soaked and contributing to the issue, Still no luck...

http://i73.photobucket.com/albums/i235/Neil_85/Miyukis%20Silvia/DSCN5391.jpg
http://i73.photobucket.com/albums/i235/Neil_85/Miyukis%20Silvia/DSCN5392.jpg
http://i73.photobucket.com/albums/i235/Neil_85/Miyukis%20Silvia/DSCN5393.jpg

My Theory:
I noticed there is a sensor on top of the A/C compressor, Which appears to be a temp sensor according to FAST. So my theory is the bad bearings are causing excessive heat and tripping the sensor.
http://i73.photobucket.com/albums/i235/Neil_85/Miyukis%20Silvia/DSCN5390.jpg

So yeah I just want confirmation before I have to buy a another Compressor and have to get my Freon reclaimed again and do all this shit again.

[Sileighty_85]

Another thing

Who know what the hell this is.
http://i73.photobucket.com/albums/i235/Neil_85/Miyukis%20Silvia/compressor_ac_lines.jpg

Best i can think of is its a oil baffle to keep a steady stream of oil going to the compressor?

I notice that J-Spec S-Chassis dont have them.

Is it needed?

[redline racer510]

Man those are all really good questions,wish I can help. Hope I dont run into any of these problems. What usdm Nissan compressor is compatible just in case you need to replace, or is it a compressor exclusively made for the rb25?How much ac oil did you put in?

[Sileighty_85]

For some reason FAST wont cross reference the compressor, so i dont know.
Had a shop do it so i dont know how much oil is in it but that was a possibility and I was gonna have them add more oil today but just woke up so gonna have to wait for tomorrow

[redline racer510]

updates??????????????????????????????????????????

[Boostin240sx]

I always thought the thing in the picture on your second post was an accumulators.

I second the notion about the oil. If they didn't put enough oil in it, it will cook your bearings.

[Darius]

Yah oil. When the shop charged the A/C system, are you sure they put in enough oil? If not, the compressor will grind itself to pieces.

[Sileighty_85]

Thats what Im figuring it needing more oil.

Still havent made it to the shop, cant seem to get my ass out of bed early enough.

[redline racer510]

let me know how it turns out btw how much oil does the fsm say to inject?

[Sileighty_85]

well i went to the shop they added more oil but its still doing it, Im just gonna locate another Compressor and swap it out

[S14DB]

Did the AC shop flush out the parts that were reused? What oil did they use? Did they watch it cycle for a while? Is the compressor a VCR like the KA?

I can see it being one of 3 problems:
Clog in the lines.
Wrong Oil.
Bad charge level.

The system is definitely seeing something wrong and shutting down then restarting when it's happy.

The shop should hook it up to the gauges and watch it cycle for a while until the problem starts happening.

[Sileighty_85]

Nah I couldnt get the system flushed, turns out theres no dedicated A/C shops around here....

They have that automatic machine that pulls Vac, adds oil and charges.

Lines shouldnt be clogged, worked fine before the swap, and the A/C cools when its engaged.

Hey hooked up the gauges to the car while running and said everything looked good, even during the grinding

I just think the bearings are bad and just gonna go ahead and replace it.

I'll probably be able to pick one up pretty cheap when I head to Okinawa to visit the inlaws

[redline racer510]

Is there a dedicated type of oil for these compressors or will the kragen/autocrap oil suffice. I wonder if nissan sells a/c oil

why not just replace the bearing your self

[S14DB]

Nah I couldnt get the system flushed, turns out theres no dedicated A/C shops around here....

They have that automatic machine that pulls Vac, adds oil and charges.

Lines shouldnt be clogged, worked fine before the swap, and the A/C cools when its engaged.

Hey hooked up the gauges to the car while running and said everything looked good, even during the grinding

I just think the bearings are bad and just gonna go ahead and replace it.

I'll probably be able to pick one up pretty cheap when I head to Okinawa to visit the inlaws
How long were the lines open to the ATM? Just to swap lines or did it sit for a while?
Is there a dedicated type of oil for these compressors or will the kragen/autocrap oil suffice. I wonder if nissan sells a/c oil
There are 2 different types of 134a oil. PAG(Polyalkylene Glycol) and POE(Polyolester) Oil.
PAG is the most common and comes in 3 weights.
PAG (ISO) 46 - Thin
PAG (ISO) 100 - Medium
PAG (ISO) 150 - Thick

We use PAG 46. But shelf stock is 100

why not just replace the bearing your self
Rebuilding a VDC is no easy task.

[Sileighty_85]

How long were the lines open to the ATM? Just to swap lines or did it sit for a while?

There are 2 different types of 134a oil. PAG(Polyalkylene Glycol) and POE(Polyolester) Oil.
PAG is the most common and comes in 3 weights.
PAG (ISO) 46 - Thin
PAG (ISO) 100 - Medium
PAG (ISO) 150 - Thick

We use PAG 46. But shelf stock is 100


Rebuilding a VDC is no easy task.

they were somewhat open since I pulled out the KA had the HP side plugged but kinda hard to keep the LP side right above the turbo sealed.

Not really sure on the oil it seems pretty thin and had dye mixed in from what they said , I fig the shop knew what they were doing.

haha yeah I dont plan on trying to rebuild it.

When I do get a newer compressor I'm gonna find a real shop and have them flush the system and all.