Automotive Air Conditioning Information Forum (Archives)

texan4ever on Mon July 09, 2012 1:43 PM

Year: 2001
Make: Toyota
Model: Tundra
Refrigerant Type: 134a

I just bought a 2001 Toyota Tundra. When I got the truck it had almost no refrigerant. I charged the system a few days ago and it was performing very well (90 degrees in the garage and 44 degrees coming out the duct). However, I suspect it may have a small leak in the system. I am in the process of adding dye to the system so I will know in a few days.

If I evacuate the system, what components should I replace, if any?

How long can the system typically be in an evaluated state, before the dryer needs to be replaces (I may replace all the O-rings on the fittings as preventive maintenance)

Should I flush the system while I have it evacuated ( I plan to keep the vehicle for 5 to 10 years).

Thanks

My background:
Electrical Engineer. I have previous experience overhauling a 97 Dodge Caravan. I have done a R12 to R134a conversion on a 1990 Mazda Miata. (I probably did not do everything to spec. I want to do it right the first time on the Toyota)

Equipment I own:
30 lb tank of 134a (thank you Sam's club)
Master Cool gauge set
Vacuum pump
UV light
Dye injector
Air Compressor
Haynes Auto AC service manual

mk378 on Mon July 09, 2012 6:06 PM

Add the dye and see if that helps find the leak. If it never leaked all the way down to zero, there won't be much water in there but considering the drier is 11 years old it should be replaced should you open the system for repairs. For pre-emptive replacement you could consider the o-rings on both ends of the line from the compressor to the condenser, that part runs hot and tends to harden o-rings. I wouldn't mess with any other connections that aren't leaking and don't otherwise need to be disconnected. Don't leave a system in vacuum for days, evacuate to do a leak-up test, if it passes, evacuate again and charge right away. Charging an empty system from a 30 lb tank you need some sort of scale to get the charge amount right.

Edited: Mon July 09, 2012 at 6:08 PM by mk378

texan4ever on Wed July 11, 2012 9:27 AM

Thanks for the reply. This makes sense. Two more questions:

Do I need to add any more oil to compensate for what leaked out with the refrigerant? When replacing the dryer, do I just drain the oil from the dryer into a container and then refill with the same amount?

Thanks

Edited: Wed July 11, 2012 at 9:30 AM by texan4ever