Part 8 - Rear Heater Install

In the warmer seasons one can go without a heater of any sort, and not even think about it. You can be driving your Subaru powered Vanagon with the windows down, hair dancing in the wind, and thoughts of tubing the river - then Fall hits - and there is frost on the ground.

At some point you will really appreciate having heat in your aircooled Vanagon turned SubaruVanagon. This article details how we installedl a rear heater into our formerly aircooled 82' Westfalia. We used parts from a watercooled Vanagon and followed the same layout as the watercooled Vans. Follow along with us and get some heat on!

 Overview and Approximate Time Needed :


Process Description

~ Time (hours)


Install rear heater assembly



Install heater lines



Install heater cabling and switch






* Approximate Total Time =


*When you factor in rest and prep time, a mechanically inclined person should reserve a half day to complete this process.  For someone new to working on cars, this may take a day of work.


Tools you may need:

1.       Drill and drill bits (long drill bit makes finding hole easier)

2.       Masking tape

3.       Reciprocating saw

4.       Hole saw drill bit

5.       Funnel for coolant 

Step 1: Install rear heater assembly

Step 1 or Step 3 could be completed first, but I chose to physically install the heater assembly first. This step is fun because there is a good amount of progress seen, and you can almost feel the heat pour from the fins even though it sits idle.

Step 2: Install heater lines

Once the heater assembly is in place we can run the heater lines and connect them to the motor and get warm coolant flowing through the heater core - so close to having heat! 

Step 3: Install heater cabling and switch

Now that warm coolant is coursing through the heater core we need to push that heat forward and out so passengers can feel it. This step requires some mild wiring skill and can be tricky, but it will pay off, I swear!


Doesn't the heat feel nice on your cold toes? This step is fairly straightforward and can be completed in a morning if you're quick. If the rear heater isn't enough heat for you, continue to the next Part and we'll show how we took apart the dash and installed a front heater core and blower assembly into our aircooled Westfalia.