How to recharge air conditioning on a 1991 Buick Lesabre?

Answer 1

You will need to convert the A/C system to either R134A or an R12A type refrigerant, since the original R12 is no longer legal for sale.

To accomplish this, you will need first to evacuate the whole system, and leak test the system before adding new refrigerant. Leaks will need to be repaired. These tasks require professional equipment, and cannot be done at home. You will need to replace the accumulator (large silver cylinder with 3 fittings on it at passenger side firewall- about a $50 part). R12A charging kits can be obtained for home use at an auto parts retailer- it's a fiddly job because the gas pressures for R12A are different than for R12 and it's easy to undercharge the system. R12A Duracool has a website that gives good information, but R12A is not legal everywhere, so you may be forced to use only R134 which can only be handled by tech shops.

Probably best to get a tech shop to do the job- estimated cost if no parts like compressors etc. are bad is around $300. If you need compressor, condensor, or other parts, they are available at rockauto.com. and can add considerably to the cost. Be patient afterward- the new refrigerants don't work at the same pressures as the old R12 and the system will probably need some further attention to get it working right.