Vacuum System Installation

December 2004

Vacuum Pump Installation

One benefit of electrical vehicles is that they are very quiet. Unfortunately, vacuum pumps are known to be noisy and can easily be heard inside the cabin. In order to keep the vacuum pump as quiet as possible, it was placed in fiberglass insulation, inside a plastic housing. This housing was placed in the rear of the vehicle on foam mounting.

The vacuum pump and its housing:

...and installed in the rear of the vehicle:

Vacuum Reservoir Construction and Installation

To reduce the amount of times the vacuum pump cycles, it is nice to have a vacuum reservoir. This can easily be constructed by using PVC, two end caps and some fittings:

Hoses for Vacuum System

Selecting a nose for the vacuum system turned out to be a bit of a task. Originally 1/2" heater hose was used, however it was quickly discovered that this hoes deforms under vacuum and makes the pump work overtime. The material that was selected is called POLYFLO tubing. It is black and semi-rigid. It can be formed with a heat gun (to navigate sharp corners). Beware - whatever material you select, make sure it is semi-rigid and can withstand the automotive environment. Some materials, such as indoor plumbing, cannot withstand the outdoor punishment of an auto environment.