Q: Where is the vacuum check valve located on a vacuum assisted brake booster?

asked by on October 15, 2016

Good afternoon, my name is John and I am replacing my power brake booster in my 2007 Lincoln MKX. Was told I need to disconnect the vacuum check valve but I'm not sure where it is located. I have diagrams and what not, but none of them actually say a vacuum check valve. The paperwork I have states that the brake booster check valve must be disconnected from the brake booster prior to removing the master cylinder or the master cylinder seal may be drawn into the brake booster. By chance is the vacuum check valve located with the manifold vacuum hose assembly on the backside of the power brake booster?

My car has 178000 miles.
My car has an automatic transmission.

The check valve is built into the hose that connects to the brake booster. The hose should be disconnected from the booster connection when removing the master cylinder. If you apply vacuum to the hose after you remove it from the booster, you should be able to hold vacuum on the line indicating check valve is good. If it will not hold vacuum, then you will need to replace the line assembly with check valve built into it. If you need help with this repair, YourMechanic offers a repair and diagnosis service preformed by a certified mechanic that will commute to your location to help you replace your brake booster vacuum pump.

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