How to Replace the Master Cylinder on an Atwood Actuator 85778

Updated 08/27/2018 | Published 08/25/2018

Question:

The coupler on my trailer is welded on, and the brakes have not been serviced in some time so the fluid has many large particles in it. Wondering if I can remove the master cylinder with the top bolts after I remove the brake line? I cant see well enough, and the exploded diagram that Ive looked at on-line dont seem to help me understand, how the piston, which is on the port side of the coupler, attaches to the master cylinder/reservoir.

asked by: Paul

Expert Reply:

We actually have a video showing how to replace the master cylinder on an Atwood surge brake actuator like your part 85778 which I have linked for you to reference.

In the video you can see that once you remove the 4 screws the master cylinder can be removed but there is a gasket that seals it to the cover of your actuator so it may be a little difficult to initially move.

expert reply by: Jon G