Determining The Correct Length Of Flexible Brake Line When Installing Fold-Away Coupler Hinge

Updated 09/19/2013 | Published 09/17/2013

Question:

Hello, Looking to order the 3x3 Fulton weld on swing hinge for Escort trailer dual axle with surge-line brake actuator with 21foot Bayliner. Will the 12.5inch flexible f-f brake line be adequate, or should one of the longer ones be used? A competent mechanic/fabricator will be attaching this for me. Currently 1/4inch steel brake line runs from actuator through the tube and out where the frame Y-s out to the rest of the back of the trailer. Thank you,

asked by: Aaron C

Expert Reply:

When considering the coupler hinge, placement of the coupler is very important. I have attached a couple of drawings that show what should be considered when using a hinge coupler. One chart shows the Pivot Length maximum based on the Gross Trailer Weight Rating and the Maximum Tongue Load. The other drawing shows where the measurements are taken, which is from the center line of the trailer ball to the furthest pivot hole on the coupler hinge.

You will need to shorten the existing brake line by coiling it inside the stationary part of the tongue (always coil from the top down not bottom up or sideways) or by cutting the line, reinstalling the fitting in the correct direction on the line and double flaring the end of the cut brake line.

Make sure that you do not install a flexible line that is too short, which would be damaged when the coupler is opened. Also keep in mind if you install a flexible line that is too long, it could wind up being pinched and damaged when opening the coupler. I have attached a product review video for the coupler. I have linked you to some of the flexible brake lines of various lengths that we offer. Your installer/fabricator can determine the best length needed based on the pivot length of your trailer tongue.

expert reply by: Jeffrey L