Tie Down 850E - Manual (Page 3)

IMPORTANT: READ AND UNDERSTAND THE ENTIRE INSTRUCTION/ASSEMBLY
PROCEDURE BEFORE INSTALLING YOUR BRAKES AND ACTUATOR.
The Model 850E works by the “surge” or “push” of the trailer toward the tow vehicle.
This automatically synchronizes the trailer brakes with the tow vehicle axle brakes. When
the trailer pushes against the tow vehicle, the actuator telescopes together and applies
the force to the master cylinder, supplying hydraulic pressure to the brakes. The built in
dampening shock absorber retards the telescoping shock against the hitch ball.
Be sure to comply with regulations for brakes in your state. Brake laws sometimes are
minimum standards and you may wish to add additional brakes to your trailer.
Read your tow vehicles owner’s manual on towing capacity and other towing
recommendations before installing brakes or this actuator. The Model 850E Actuator is
completely assembled and ready to bolt into place, if not all ready installed. Manufactured
for tongue sizes: 3”x 3”, 3”x 4” & 3”x 5”.
1. Bolt the actuator to the tongue-using grade 5 bolts 1/2 inch in diameter, 4 inches
long. Lightweight tongues, less than 11 gauge, require spacer tubes inside the
tongue for reinforcement. Attachment strength should equal or exceed than
1-1/2 times trailer G.V.W.R..
2. Hydraulic brake lines should be installed on the trailer as described in the
installation manual supplied with the brakes. Note: Some disc brakes require the
use of flexible brake lines at the connection POINT on the brake caliper. Follow
brake manufacturer instructions.
3. Use only DOT-3 heavy-duty brake fluid in the Model 850E actuator. Use a pressure
type brake bleeder to bleed brakes. (This type of brake bleeder is available at your
local automotive jobber.) Follow manufacturer’s directions. Or, manually bleed the
brakes using a heavy-duty flat blade screwdriver inserted in the hole provided on
top of the actuator near the front. Insert the screwdriver and use a pumping action
to activate the master cylinder in order to bleed the brakes.
See page 7 for more details.
To bleed master cylinder and brakes, install bleeder hose on first wheel cylinder to
be bled; if tandem axle trailer, bleed closest axle first, and the closest brake on that
axle first. Use a loose end of hose from the bleeder valve submerged in a glass
container of brake fluid to observe bubbling (hose must be submerged into clean
brake fluid to keep air from traveling back into the brake cylinder). Loosen the
bleeder screw located in the wheel cylinder one turn, the system is now open to the
atmosphere. The bleeding operation for that brake is complete when bubbling stops.
Be sure to tighten bleeder screw securely.
Each wheel cylinder must be bleed until all air is out of the lines. Replenish the
brake fluid during the bleeding process so the level does not fall below half full level
in the master cylinder reservoir. When bleeding and testing is completed, make sure
master cylinder is filled to 3/8” below the top of the reservoir and filler cap is
securely in place.
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