Heater core lines

Up next was connecting the heater hoses to the heater core. The Mazda heater core in/out is located on the driver side while the in/out on the engine is on the passenger side. The “easy” solution to this is just run heater hoses under the hood to the factory Mazda location on the driver side and work fine. However I did not want rubber hoses draped across the top of the engine and the location on the driver side of the firewall is pretty tight to connect to. The alternative solution that was used is to run new copper hard lines from the heater core on the driver side to the passenger side under the dash which gives a straight connection to the engine. It took a few tries to get the angles right but it came out ok. I had the copper line pressure tested as well. They held 80psi of air for awhile so I should be alright...I hope!

Interior:



Driver side heater core in/out:



Passenger side:



Under hood: