Bill Speed

Mine's been empty pretty much since I got the car with 43+ thousand miles! I never bothered to convert, but my other car I recently got from eBay for $510 total has new A/C conversion already and does blow cold. Sadly, my experience is once you turn it off, it takes a matter of minutes to disapate back to the sun drenched heat thru your glass windows. I have blue leather in my Cad and gray cloth in my 'Bird, which is a convert and my major concern there is sunburn. I plan to revamp the A/C in that one as well and one estimate here was about $600 to do it w/o a new pump at the time likely included, though that car is now gone, the price is probably around $300~$400

Bill

ScrapMaker

is there anyway to speed up the vacuum process to about 30 minutes? what level of vacuum can I safely bring it down to, in hopes of speeding it up? My friends make telescope mirrors in a giant vault, and I bet I could use one of their vacuum pumps to speed it up.

1. you put the flushing liquid in the system, (after you pull the oriffice tube and the dryer,) and blow it through with an air compressor, right? or is the stuff already pressurized? Also, is it better to leave the oriffice tube in, or take it out before you flush the system?

2. anyhow, I guess you'd want to blow it out with a compressor after all that, to get most of the liquid out...

3. pour the oil in the compressor (10oz give or take?)

4. then pull the vacuum on the system...

5. LEAVE the vacuum in the system while you add the r134a from the cans.

DENN_SHAH

iTrader: (1)

Lucid, going to the bigger condenser was a good move, the bigger the better.
the dual fans will also help out at idle & low driving speeds, other than those things as long as everything else is in good condition there isn't much you can do.
the outside of the evaporator core could be dirty which will cause reduced air flow through it, the only thing i know of that would really work for that is either pulling it out & cleaning it with some coil cleaner which is made for that job (not the enviro type of cleaner, that stuff sucks) or replacing the evap core with a new 1. cleaning is cheaper but there is the risk of the cleaner eating away at the old core & causing it to leak. if all of the cleaner is
not washed off the core then it will continue to eat away on the core & then leak. either way its a lot of work & may not yield much improvement.

ScrapMaker, i run 8 oz in my system, i put 4 in the compressor & the rest in the accumulator.
to flush the system out, everything needs to be disconnected. there are some flush kits that are pressurized, most shops buy flush by the gallon that is poured into a container that is then pressurized & used to flush the system out.
there really isn't anyway to speed up the evac process. a good vacuum pump will pull a clean system with no leaks down to its maximum vacuum in about 5~10 minutes. but no matter how fast or how deep the pump can pull, it still takes time to boil the water out.
around 45 minutes seems to be the standard amount of time most places evac a system,.. a full hour is better.
the deeper the pump pull will down the better, most pumps are rated not just how fast they can pull down, but the most important part, how far they can pull to.
here is a site with some info & a chart showing at what temps & vacuum water starts to boil at.

http://www.robinair.com/new/acsoluti...m/acvacuum.php

yes, leave the system under vacuum when you recharge it.

ScrapMaker

well I was worried about the seals on the system... because my friends have a tank they put a vacuum on, then they use it to powder coat/aluminize stuff...

they even have an oil-sump vacuum pump...

although, I may as well just use the standard A/C vacuum pump, as my friend has one of those too.

so is there anything I can SEE, or HEAR to know that I'm getting to the point where I can just stop the process if I'm in a hurry?

Lucid

iTrader: (4)

I forgot to show you my dual fan conversion, this thing runs sweet, especially with the A/c on. I first bought an aluminum Modine radiator, these things are awesome. I had to cut all the damn mounting tabs off the fans, which required a lot of trimming so they would fit and clearance all the junk in the engine compartment. Then the lips along the edge of the shrouds didnt allow the fans to fit inside the tanks of the radiator. So i grabbed a bench grinder and meticuously grinded them down until they fit snug inbetween the tanks. I ran cable ties through the radiator with carefully drilled holes, and wrapped it up by cutting the upper radiator cover with a saw to keep it looking stock. The wiring was the hardest part since no one makes a connector for these Valeo fans since they are from Europe, they are quiet but VERY powerful. I bought them from Ramchargers, and it was cheaper to buy the Modine Aluminum radiator and Dual Fans together than just to buy a BeCool Radiator by itself without the fans.

Cheers!
Lucid

ScrapMaker

did you wire the fans to run independently like a 4thgen? the main reason for getting 2 fans is so if the temps are slowly creeping up, you can just run one fan, on and off... but if it's hot, and you have the AC on, then both will be running full blast...

if they don't run independently, you may be better off with one monsterous fan instead

Mcdamit

Is it really that hard to get some R-12? I got like 5lbs. of the stuff for free..

ScrapMaker

it's pretty hard to get nowadays... shops can still get it... but it costs an arm and a leg.... you got lucky..

Lucid

iTrader: (4)

Scapmaker,
These fans are fully capable of running at low and high speed independently (separate wires). I couldnt find a connector and then i really didnt want to mess with it too much. I got a Adjustable Fan Relay/ Thermostat from Oreillys and wired it up to a terminal block. The thermostat is capable and is wired to control both fans, and i didnt connect the low speeds. There is a probe that i ran into the radiator (i drilled a hole in the fan shroud and hid it through the radiator there). When the preset temp is hit, the fans come on and blast and then when the temp drops they shut off. When the A/C is turned on, both fans come on and blast. There is no ECM involvement in this process, since it used to be with the single fan. The GM relay was problematic and came on waaaaaay to late after the car was about to overheat. I was going to run two relays and run two probes, but i said what the hell and it runs great this way. When the alternator is charging correctly in this Texas heat and A/C going, and i dont gun it too much, the temps stay around 220 degrees. That wasnt possible with the single fan i had before, not with this engine. Although i have noticed that with the A/C on, blower full blast, stereo on, this thing is a big drain on the battery even with the Red Top i bought from autozone.
I don't know how to run them like the 4th geners...?

ScrapMaker

you probably dont NEED both fans on at the same time... I was just suggesting having one that runs ALWAYS with the A/C... then the other one turns on with the thermostat...

just easier on the charging system, that's all...

then, if it was REALLY hot outside, or you were raggin the hell out of it, you'd want both fans on even though the A/C was off... plenty of ways of doing this, but maybe through your adjustable relay or temperature sensor...



on my thirdgen, I had to wire up a switch to control the fan... I had it wired to be on AUTO (stock,) or IGNITION... I left it in ignition mode, forever... it made the A/C colder, and my car ran like 20 degrees cooler... I had a yellowtop with a regular alternator... no big problems either...


not that you really need to change anything, just food for thought... could lengthen the life of your charging system...

ringo234

Are you sure you've got the correct amount of refrigerant?
The refrigerant will only enter the system as long as the pressure in the can is higher than the pressure in the AC.
To force more refrigerant into the AC raise the pressure in the can by raising it's temperature with a hot air gun.

This is what I did for my boss's car. I had the car running with the AC on and heated the canister until the AC started blowing cold air. It worked great.

Lucid

iTrader: (4)

Scrapmaker,
Did you ever get that A/C going? My dad pulled a vacuum on my system and we refilled it, it blows pretty well right now. It helped on my drive up to Austin on the 94 degree day we just had. I had a bolt on my blower motor back out so it was spewing some of my cold air in the engine compartment. I am using audio grade butt connectors and bulb grease from now on, i had spliced a new high speed relay and the cheap ones i had put on were burning up at the connection, causing a volt drop because of the resistance.

ScrapMaker

I got the A/C going in my thirdgen almost a year ago... pull the vacuum like you said, but there was a problem with how the A/C system mounts up to the new compressor... I had to get custom spacers/gaskets... PITA...