Is The Check Valve For Demco SBS Braking System Necessary.

Published 11/17/2021

Products Featured in This Question

Demco Stay-IN-Play Duo Flat Tow Brake System for RVs w/ Hydraulic Brakes - Proportional

(845)

$1245.50

Replacement Check Valve for Demco SBS Supplemental Braking Systems

(63)

$27.24

Question:

My local mechanic did not install the vacuum check valve as noted in the instructions. Is this necessary and if so why? Tried to attach picture but it would not upload.

asked by: Tim D

Expert Reply:

The Replacement Check Valve for Demco SBS Supplemental Braking Systems # SM99909 required for all towed vehicles that don't have a diesel engine and are not Hummers.

A vacuum pump check valve for automobiles, also known as a vacuum check valve, is a part of your car that's responsible for making your vacuum pump system work. This valve seals and holds the vacuum flow up for energy-efficient and completely safe operation. You need it, for example, for your vehicle to brake properly.

expert reply by: David B