AC reinstall advice

[scottiedawg66]

hey everyone. I am putting the AC back into my 87 1jz MK3. I have had the air conditioning lines, heat exchanger, fan, compressor, out of the car for almost 10 years. Besides just hooking everything back up are there any seals I should replace, or any other maintenance I should perform? I imagine alot of crud got into that large fitting on the passenger firewall? Should I replace that? clean that? I will follow the stickies about the R134 conversion, so you can leave that out since it is well documented. Thanks SM!

~scotty

 

[hvyman]

Just flush the evaporator.

 

[3p141592654]

new receiver drier is mandatory.

 

[SC61 MK3]

I'm doing this right now. If the ac lines were open that it may need a good flush to remove anything in them. All the ac seals are cheap from rock auto and just make sure you pull a strong vacuum before you recharge it to remove any moisture in the lines

 

[scottiedawg66]

what do you all recommend using to flush the evaporator and AC lines? would a receiver dryer from a closed (stock never messed with) system from a junk car work, or do you recommend a new one?

when you recommend "pulling a strong vacuum" does that mean get some air movement through the lines? Sorry for being dense! It has been almost 5 years since I have spent any time working anything with more than 2 wheels.

thank you everyone.

 

[Maple191]

Flush the oil out (and replace with new proper amount) and purge the system with Nitrogen thats the best and proper way.

 

[scottiedawg66]

flush the oil out of the compressor is part of the R134 conversion ?

 

[OfnaRcR4]

Okay, i'd replace the drier, and the seals at the spots where its been disconnected. To get the rest of the moisture out a shop can hook up the system and pull a vacuum on it. This makes the water basically evaporate out of your lines but it can take a few hours iirc. You'll want to charge it with dye because most likely you'll be chasing leaks, seals might not be what they used to be 10 years ago. Oh and don't use leak sealer, it gums up the system.

Just one question. If you could go back and stop yourself from removing AC, would you?

 

[scottiedawg66]

of course! but I was 19 when I bought the car. alot changes in 10 years

 

[hvyman]

New dryer is like 20$.

Need to pull a strong vacuum with a a/ c machine. And then properly charge it.

 

[3p141592654]

R134 and R12 driers use different materials. The drier also has a filter so there is no way you want to reuse it. Pulling a vacuum is not optional, you need to get out the non-condensable gases from it having been opened up, as well as moisture that can cause long-term internal damage. The drier can only mop up a small amount of H2O before it gets saturated.

 

[OfnaRcR4]

of course! but I was 19 when I bought the car. alot changes in 10 years

My point exactly DON'T RIP OUT YOU AC!!!!!!!! Anywho good luck with the re-install, you've got some good advice to go with.

As for the r-12 to r-154. Yes they use different materials(i'm not completely sure everything that is involved) but i've been running r154 for a few years now and no problems so far.

 

[Maple191]

Again this is why you pay a shop to purge it with Nitrogen its innert and it can also be used to find leaks before adding R-134a and it can also help push out any moisture left in the system.

 

[slowma70]

My point exactly DON'T RIP OUT YOU AC!!!!!!!! Anywho good luck with the re-install, you've got some good advice to go with.

As for the r-12 to r-134. Yes they use different materials(i'm not completely sure everything that is involved) but i've been running r134 for a few years now and no problems so far.

fixed that for you ...lol

 

[3p141592654]

Again this is why you pay a shop to purge it with Nitrogen its innert and it can also be used to find leaks before adding R-134a and it can also help push out any moisture left in the system.

Nitrogen is a non-condensable, you don't want it in your system. Its fine to blow out the system with dry nitrogen, but you need to vacuum it out before charging, or it will impact system efficiency significantly.

more info here... http://www.refrigerants.com/pdf/NRInews-Smr11.pdf

 

[SC61 MK3]

I didnt read the above link but the procedure i use for home ac is to use a flush pressureized thriugh the line by nitrogen while the systems lines are still open. Than seal all the lines and use nitrogen again to simply pressure test the system and make sure it holds the pressure with no loss for ~20 minutes or more. Than vent all the nitrogen from the lines and use a good 3+ cfm vacuum pump to pull a deep vacuum to evaporate all the moisture from the system. Than you are ready to charge it up. And also any times the lines are opened up a new filter dryer should be used.

 

[Maple191]

Nitrogen is a non-condensable, you don't want it in your system. Its fine to blow out the system with dry nitrogen, but you need to vacuum it out before charging, or it will impact system efficiency significantly.

Let me try this again Nitrogen at 200 Psi on both the high and low side of the system while NOT running is easier and cheaper to find leaks. Instead of chasing them down with R-134a or any other refrigerent. After youve found the leaks you can REMOVE the Nitrogen out of the system not leave it in. I.E PURGE