A/C Heck Solved?

[mhuppertz]

Bumping this thread up to the top because I am getting ready to have my truck charged. So its going to get a new low pressure side line, receiver/dryer, and expansion valve. I don't plan on replacing the oil since the cans come with oil and I think there is already some oil in the system. So 1 can is the recommended charge?

Ok, I will post pictures and details as soon as I can.

[Diesel]

Thanks! I don't think I need pictures because I know where the low pressure fitting is - I'm just curious if a single can of R134 will do the trick? Your vent numbers are unreal!!!

[mhuppertz]

Thanks! I don't think I need pictures because I know where the low pressure fitting is - I'm just curious if a single can of R134 will do the trick? Your vent numbers are unreal!!!

To get it to work like I did, you need to pull a vacuum on the system. The time needed depends on if your system was open to the atmosphere and how humid it is there. It's dry as heck here so I just pulled mine down for 20 minutes. Then add a can. On my truck I pulled the temp sensor that is in the A/C line near the firewall out about 1/2 inch. Then I added just a tiny bit of another can to get it where I wanted it.
It is best to do this in the cool of the morning, and if you have a mechanical fan, use a house box fan or shop fan to force air into the condenser.

Note: With the pressures lower like this, it takes a little longer for the system to get cold, but once it does, LOOKOUT! Since I do a lot of stopping and starting during the day and don't have a lot of time for it to get really cold, I am running a can and a half. I lose the sub-zero and gain a faster cooldown.

Don't forget to replace the receiver/dryer while you are at it.

Is this helpful?

[RumbleFish]

How do you pull a vac? Do you need the fancy$$$$$$$$ ac machine or is there a backyard alternative?

[mhuppertz]

How do you pull a vac? Do you need the fancy$$$$$$$$ ac machine or is there a backyard alternative?

I used an $11 vacuum pump from Horrible Fright. It requires and air compressor to work, but it works great.

[ellis93]

Yep,or find a gas burner and take the line off the brake booster and attach it to the a/c fitting with its core removed. It'll work you just idle the gasser for awhile and you have to be fast when re installing the valve core.
Ya its redneck, but it works if you've no other way.

[Diesel]

mhuppertz - you have been incredibly helpful!

I will install a new expansion valve and dryer with my new line. What is the switch you pulled out? Is it something I can do after I install the parts and charge it?

[mhuppertz]

mhuppertz - you have been incredibly helpful!

I will install a new expansion valve and dryer with my new line. What is the switch you pulled out? Is it something I can do after I install the parts and charge it?

It's not a switch, it's actually a temp probe that slides into a sealed fitting on the cold side pipe by the firewall. It is held in by some sort of paste. If you live in a humid climate, just pull it out a little at a time so that you don't ice up.

[Diesel]

Got it! Right now its on vacuum. I put in a new dryer so I really don't think I need more than 20-30 minutes of vacuum...probably fine with 10-15 but whatever.

[mhuppertz]

Got it! Right now its on vacuum. I put in a new dryer so I really don't think I need more than 20-30 minutes of vacuum...probably fine with 10-15 but whatever.

Sweet!

[Diesel]

Good thing I put this on a vacuum before having it charged! The gasket on the side of the new driver that takes the hose that has the high pressure fitting was losing vacuum...replaced the gasket and hoping its not the line. Hopefully I can get a shop to give me a good charge tomorrow.

[Diesel]

Is there supposed to be an O-ring on the hose ends that go on the dryer? I changed the gasket and it still would lose pressure. I just put an o-ring on the end of the metal nipple and it maybe holding vacuum but will it hold pressure?

[collegekid]

Can you post a pic of the temp probe you pulled out the 1/2"? PLZ

[Diesel]

I don't have a picture but you won't miss it. Look at where the lines hookup to the firewall. There is a copper probe going into a hose. Thats the sensor lead that can be pulled in and out - I do not know what difference it would make but I pulled mine out 1/2" based on the forum suggestion.

[collegekid]

And the ultimate purpose of pulling that out makes the compressor run longer?? Hence more cold air longer? Its a steady 105-110 down here and I wouldnt mind a colder A/C, or maybe a more powerful blower