Tie Down 66 Actuator For Serial #16020 and above - Manual

TIE DOWN ENGINEERING • 255 Villanova Drive SW • Atlanta, GA 30336
www.tiedown.com (404) 344-0000 Fax (404) 349-0401
Installation Instructions and Service Manual
Model 66
Actuator* for
Trailer Brakes
6600 lbs Capacity
Part #47210/86167 - Drum Brake Ready
Part #47211/86165 - Disc Brake Ready
* US Patent No. 6,375,211
MODEL 66 ACTUATOR INSTALLATION INSTRUCTIONS
IMPORTANT: READ AND UNDERSTAND THE ENTIRE INSTRUCTION/ASSEMBLY PROCEDURE BEFORE INSTALLING YOUR
BRAKES AND ACTUATOR.
The Model 66 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 by depending on the brake fluid in the master cylinder. Low levels of brake fluid will signal the tow vehicle operator to add
brake fluid via hitch ball knocking.
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 66 Actuator is completely assembled and ready to bolt into place (Tongue sizes: 3”x3”, 3”x4” & 3”x5”).
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. Tie Down’s actuators feature a shock dampener that uses brake fluid from the master cylinder. The dampener must be primed before
bleeding or using trailer. To prime the dampener, fill the master cylinder with DOT 3 brake Fluid. Push the coupler into the housing
and slowly pull out 3 times, then refill master cylinder. Failure to do this step will cause actuator problems that could lead to brake failure.
4. Use only DOT-3 heavy-duty brake fluid in the Model 66 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 8 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.
090810,C100
Instruction #15359