Evaporator Core replacements can be done in a relatively short time

When I went to work for a GM dealership some years ago, I was amazed that no one wanted to touch the evaporator cores in the C & H bodies made throughout the 90’s. Their reason was simple; everyone felt it didn’t pay enough. Therefore, everyone quoted the job high, hoping the customer wouldn’t give approval so they could flag the check-out time and move on to the next job.

What everyone hated about this repair is two-fold. First is the rubber insulator covering the evaporator housing that needs to be cut for removal; second is removing the instrument panel (I/P) to access one bolt that retains the evaporator housing from the inside.

The hard part first — cutting the heavy rubber cover on the evaporator housing. What makes cutting the insulator difficult is it needs to be cut behind the right strut tower, and the cover wraps under the evaporator housing out of sight. The solution is simple. Take a long pry bar, one with a slight angle on the end, and give it quick edge with a file. This gives you a cutting tool with good control and the ability to easily maneuver underneath the housing. Also, cut just outside of the indicated cut area; this will expose the two screws securing the right side of the evaporator housing.

Now, the easy part — removing the I/P. Don’t do it! The reason the I/P needs to be removed is for that one screw. Removing the I/P can be very time-consuming and introduces the possibility of causing rattles, squeaks, etc. So, once everything else has been removed exposing the evaporator housing, remove all the exterior screws securing the housing. Then locate the plastic fastener below the blower motor opening. Using the same pry bar, work through the blower motor opening and GENTLY pry the housing away from the firewall. Move from one side of the retainer to the other, loosening the housing in multiple small steps. What you’re achieving is a slight bend in the housing where the plastic retainer is secured. Taking it slow and easy will free the housing from the retainer with out any damage to either. Once free, simply peen the housing flange flat. Leaving the plastic retainer secure in its original position will aid in the installation by allowing the housing to snap and hold its position during the installation.

Also, once the evaporator is removed thoroughly clean the water separator. Clean, dry and disinfect it using a pleasant smelling disinfectant spray. This will eliminate that musty smell and give a fresh scent that will be noticed and appreciated by the customer.

With a little practice, you can easily complete this repair in less than a couple of hours; significantly less than book time. Using these “tips” you can provide a quality repair at a fair price and earn customer respect. Although it may be a bit tougher, this will also work on similar Cadillac body styles.