What does the evaporator service kit actually correct? My quick read shows it contains foam strips and tape. It appears to be more of an efficiency booster than a leak fix.

 

https://miamibritish.com/shop/land-r...lr097253-behr/

It includes the evaporator with the metal hoses attached to it on one end and a new expansion valve on the other end, as well as the supplies for installation, such as asphalt tape, etc.

 

That looks good. Thank goodness for service kits! I used one for my vacuum pump. The availability of service kits is a good indicator of the weak points in a vehicle.

 

More like an indicator of what tech at a high volume dealer complained about.

 

Gather around, boys and girls. Uncle Fly has a good horror story for you.

We got the service kit, and my mechanic proceeded to remove the old evaporator from the heater box according to the service manual instructions. What he found instantly confirmed the source of the problem.

This thing here is what's left of a line that runs from the evaporator to the expansion valve. What you see here is the end of the fitting that fits into the valve. It's been cleaned up a bit to highlight the problem. Hard to miss!



That is corrosion on the aluminum of the pipe. Specifically, a combination of pitting and exfoliation corrosion. The corrosion has eaten through the pipe, which explains why there was dye on the expansion valve and no refrigerant in the system soon after being recharged. But you can't see that if you remove the expansion valve from the engine compartment side, because it's on the side of the pipe facing the cabin. Closer detail with my USB coin microscope shows the extent of the damage.



So, $1500 later (mostly labor, the evaporator kit was $311, plus a few misc doodads), I have a working a/c. It's summer, and the car is still all mine. Money comes, money goes, but the cool cabin is worth it.

So now you know. Put some WD-40 all over that to inhibit the corrosion on all the hardware. Be generous -- it won't hurt anything if you slosh it around. Especially if, like mine, your car spent any serious amount of time near salt water (the previous owner spent a lot of time with his family in Cape Cod). Why this wasn't treated for corrosion prevention by the subcontractor who made is going to be another one of those mysteries...

 

So the only part that actually required replacement was the line that had corroded?

Good tip on spraying WD-40. They make a special version (WD-40 300035) to inhibit corrosion.

 

No, the pipe is an integral component of the evaporator. You can't buy it separately. The piece that I have was cut off from the remainder of the pipe.
No need for a special version. The original WD-40 is specifically meant to prevent corrosion. WD = Water Displacement, developed to inhibit corrosion on missile exterior skins in long term silo storage under less-than-ideal conditions.

 

I think the special version marketed for rust (Corrosion Inhibitor) is formulated to cling longer to extend the rust prevention for 1 - 2 years. Regular WD-40 benefits don't last much longer than a day or so.

 

Regular WD-40 dries to a long lasting film that is what gives you the protection. If it only lasted 1-2 days the government would never have bought it. Don't believe all the marketing BS. 😁