1949 Chevy Heating and Air Conditioning - Crimps 'n' Hose

Once the correct die for the size hose was selected, it was installed in the tool, which was mounted in a vise.

The hose and fitting were then placed in the die, ensuring they were still in alignment, and the bar at the top of the tool locked in place.

The small arm that's been swung round against the fitting since the last picture is a height guide, with the fitting pushed up against it, ensuring the crimping is done in the correct location. An air wrench was used to tighten the tool, and hence crimp the fitting.

I used stock GM pulleys on my motor, but the water pump pulley ever so slightly fouled on the body of the Edelbrock water pump. Speedway Motors sell these pulley shims to provide correct alignment. I only had to use one 1/16-inch shim, though the kit contains two 1/16- and one 1/8-inch shims. On the left is a crankshaft pulley spacer to match the upper pulley's alignment.

Here's what the finished crimped fitting should look like, OEM style and leak free.

The drier has to be located between the condenser and the evaporator. I mounted it at the front of the inner fender, which obviously needs a little repair work before it's ready for paint!

The condenser (listed in the Vintage Air catalog as for a '39-40 Ford or '55-57 Chevy) was mounted in front of the radiator, a triple flow design from U.S. Radiator, using Vintage Air's universal brackets. Be sure to mount the condenser with the larger No. 8 fitting at the top. The refrigerant lines were routed through the radiator support panel and will eventually pass through suitably sized grommets.

I used stock GM pulleys on my motor, but the water pump pulley ever so slightly fouled on the body of the Edelbrock water pump. Speedway Motors sell these pulley shims to provide correct alignment. I only had to use one 1/16-inch shim, though the kit contains two 1/16- and one 1/8-inch shims. On the left is a crankshaft pulley spacer to match the upper pulley's alignment.

Alignment of all the pulleys is vital, and now's the time to check it. I used an over-long belt to check that all the pulleys were true in relation to each other.

In order to tension the belt while checking the pulley alignment, I used Vice Grips to clamp the excess under the crankshaft pulley.

With all the refrigerant lines plumbed in the engine bay, I moved to the interior. With the evaporator removed, this is how the fittings pass through the firewall using the tube I fabricated last month. I routed the heater hoses at the top, and the A/C lines at the bottom, as they're not as flexible as the heater hoses and there's limited room for maneuver once the evaporator is installed.

Both the heater hose (shown here) and refrigerant line fittings use rubber O-rings to seal the joint. Applying a little refrigerant oil (supplied) ensures they don't snag, tear, or otherwise get damaged during installation. Add a couple of drops of refrigerant oil to the threads on the fittings as well.

I installed the heater fittings and this beadlock refrigerant fitting before bolting the evaporator in place, as they're almost impossible to get to afterward in my application. Actually I installed over-length heater hoses, ensuring the hose clamps faced downward should I need to access later, and crimped the beadlock fitting to an over-long refrigerant hose, meaning I could fine-tune their lengths once the evaporator was in place.

I had to make all the interior hoses 4 inches longer than necessary in order to be able to pull the bulkhead fitting out slightly, enabling me to tighten the fittings. Hose clamps still have to be added to the heater hoses here. While my idea was to use the original fresh-air tubes to hide much of the A/C and heater plumbing, I'll admit I made life unnecessarily complicated for myself with this arrangement.

This picture belies just how tight for space everything is in this corner of the firewall. I even had to move the evaporator up by an inch, which puts it close to the wiper mechanism, in order for the heater hose you can see running across the top of the others (arrow) to clear. If only I'd welded up that huge hole in the firewall and used a regular bulkhead fitting as it was meant to be used, it would have been simpler.

With the plumbing complete, I ran the duct hose from the various ports on the evaporator to the original Chevy de-mister vents, and to where I'll mount the louvers. Be sure to slightly stretch the duct hose and make the turns as smooth as possible to maximize airflow. But more on that particular part of the project another time!

Next came the easy part; hooking up the wiring harness. Vintage Air makes this simple in the extreme and the power and ground harness is simply plugged into the evaporator next to the control panel wiring. Be sure to run the main harness ground to the negative terminal of the battery. Good grounds are essential with any electronic system.

More simplicity. This harness also plugs into a female plug on the evaporator. The white wire is ground while the red leads to a 30-amp circuit breaker.

Here's the circuit breaker (top), while the two relays are for the heater control valve and the A/C compressor. These are supplied pre-wired and the wiring diagram in the comprehensive instruction booklet is simple to follow. I mounted these just in front of the A-pillar, where they'll be covered by the kick panel.

This is the trinary safety switch, which not only cuts off the compressor clutch at 30 psi or 406 psi, but also sends an electric fan engagement signal at 254 psi. Connect the trinary switch fan trigger to the same relay as your engine temperature switch. This arrangement will engage the fan with either engine temperature or A/C pressure. If you're running a mechanical fan, you only need a binary safety switch to cut off the compressor clutch at the high or low pressures. The trinary switch is mounted on the outside of the bulkhead fitting in the line between the dryer and the evaporator. It can be installed anywhere in the high-pressure liquid line between the condenser and the evaporator.

Mounted in the heater line from the intake manifold to the evaporator, the heater control valve flows left to right (as shown here). The valve is directional, so pay attention to the arrow on the decal. Remember that the hose from the intake manifold is the high-pressure side, while the water pump is the low-pressure (suction) side. The heater control valve installs in the high-pressure line!