/15 BH20023, Rev 15 Page 1
DEMCO MODEL DA91 ACTUATOR Model DA91 is a heavy duty surge brake actuator for trailers with two or four wheels. When brakes are applied on the towing vehicle, forward inertia of trailer toward towing vehicle applies brakes on trailer in direct relation to manner brakes are applied on towing vehicle. Brake pressure applied on tow vehicle will cause equal response on trailer brakes. Master cylinder push rod spring assembly protects system from hydraulic pressure overload.
SAFETY TAKE NOTE! THIS SAFETY ALERT SYMBOL FOUND THROUGHOUT THIS MANUAL IS USED TO CALL YOUR ATTENTION TO INSTRUCTIONS INVOLVING YOUR PERSONAL SAFETY AND SAFETY OF OTHERS. FAILURE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN INJURY OR DEATH. THIS SYMBOL MEANS ATTENTION BECOME ALERT YOUR SAFETY IS INVOLVED! SIGNAL WORDS warning: Note use following signal words DANGER, WARNING, and CAUTION with safety messages.
SAFETY sign locations Types of safety sign and locations on equipment are shown in illustration below. Good safety requires that you familiarize yourself with various safety signs, type of warning, and area or particular function related to that area, that requires your SAFETY AWARENESS. This decal positioned as shown BRAKES ON BRAKES OFF DO NOT TOW TOWABLE BH21003 Part # BH21003 Safety sign care • Keep safety signs clean and legible at all times.
Before operation: • Carefully study and understand this manual. • Always wear protective clothing and substantial shoes. • Give equipment a visual inspection for any loose bolts, worn parts, or cracked welds, and make necessary repairs. Follow maintenance safety instructions included in this manual. • Be sure there are no tools lying on or in equipment. • Do not use equipment until you are sure that area is clear, especially around children and animals.
Following operation • Following operation, or when unhitching, stop towing vehicle, set brakes, shut off the engine and remove ignition key. • Store unit in an area away from human activity. • Do not permit children to play on or around stored unit. • Make sure all parked units are on a hard, level surface and engage all safety devices. • Wheel chocks may be needed to prevent unit from rolling.
• Always use proper tools or equipment for job at hand. • Use extreme caution when making adjustments. • Follow torque chart in this manual when tightening bolts and nuts. • Openings in skin and minor cuts are susceptible to infection from brake fluid. Without immediate medical treatment, serious infection and reactions can occur. • Replace all shields and guards after servicing and before moving. • After servicing, be sure all tools, parts and service equipment are removed.
ACTUATOR PARTS BREAKDOWN **16 13 17 8 14 **10 See Page 11 for additional Slider Tube and Outer Case options 18 **12 25 30 26 1B 6 22 ** 21 5 2 20 9 7 4 27 19 24 2 28 1A 3 5 4 Optional Straight Tube Slider 5939 Manual Free Back Lock Out Kit 15 14 23 19 Model 91 ACTUATOR PARTS LIST REF. NO. PART NO. QTY. DESCRIPTION 1A. 13689-95 1 2” Ball Coupler Bolt On eZ-Latch 1B. 12925 2” Ball Coupler Bolt On 2. 01896 3 1/2”-13UNC x 4” Hex Head Bolt (gr.5) 3.
ACTUATOR KITS & OPTIONS 5(9 (&1 '$7( ')70 $ %9'3 % ** 2” Lever Lock Coupler 2” eZ-Latch Coupler 2 5/16” eZ-Latch Coupler 5876 eZ-Latch Repair Kit (' ' /8 0$< +$9( 72 *5,1' 3,1 72 ),7 5398 Master Cylinder Repair Kit (drum) (gasket 09153 included) 1& , 7 12 & 3$57 187 1& 1
WARNING: To Avoid Personal Injury or Property Damage, Observe THE Following Instructions: The weight rating of the coupler is dependent on the correct bolts being used. You must use the exact size, grade and number of bolts as specified in your manual. Mounting hardware can be obtained from a supplier or Demco.
OUTER CASE OPTIONS AND AVAILABLE HITCH CONFIGURATIONS 37 40 38 39 41 42 57 60 2-5/16” RATED 8000# 45 46 56 54 43 55 51 54 43 48 47 44 RATED AT 8000# 54 53 54 56 RATED AT 8000# 44 56 54 54 52 2 ” RATED AT 7000# 2 -5/16” RATED AT 8000# 54 56 2 ” RATED AT 7000# 2 -5/16” RATED AT 8000# 56 58 56 61 50 54 49 59 54 2” RATED AT 6000# 62 2 ” eZ-Latch RATED 8000# 54 2 -5/16” eZ-Latch 8000# 2 -5/16” RATED AT 8000# 64 63 65 54 54 54 2 -5/16” eZ-Latch RATED 8000# 66 2” eZ-Latc
BC20020 REV 0 eZ-Latch Coupler Operation 2" & 2 5/16" Couplers (4) 5/8" Grade 5 Bolts are required with channel mounted 2" & 2 5/16" couplers (1) eZ-Latch couplers do not require users to lift the handle for the coupler to engage the ball. Position the ball in the center of the ball socket or slightly forward, then begin to lower the coupler with the jack on the trailer.
WARNING • • • DEMCO MODEL DA91 BRAKE ACTUATOR To Prevent Serious Injury Or Death: Review all of the following instructions before installation and use of hydraulic brake actuator. Dealers or Distributors must review these instructions with ultimate user. Failure to follow these instructions, or failure to properly maintain braking system after installation, can result in loss of braking action which could cause severe property damage, personal injury or death.
SERVICING THE EMERGENCY LEVER (SEE PAGE 11 FOR BREAKDOWN AND REFERENCE NUMBERS) If emergency lever (#16) of actuator is applied, it can be disengaged by using a screwdriver to lift upward on front of flat emergency lever spring (#12) while pulling lever forward until released. A thorough inspection of emergency lever, emergency lever spring, and safety cable is required. Damaged parts must be replaced as follows: a. Remove master cylinder (#21) and push rod assembly (#18).
Rue Ring Installation To install Rue Ring, place straight wire of Rue Ring through hole in pin as shown in illustrations ( Figure B 1- 2) Next, using a pliers, twist end of Rue Ring so the straight wire crosses over top of the bent wire. ( Figure B 3) Figure B illustration 4 shows removal of Rue Ring. Uncross wires, then while lifting the bent wire, pull on loop end of the Rue Ring to remove from pin. Locked 4010 320th St. P.O. BOX 189, BOYDEN, IA.
P.O. BOX 189 4010 320th St., BOYDEN, IA. 51234 PH: (712) 725-2311 FAX: (712) 725-2380 TOLL FREE: 1-800-54DEMCO (1-800-543-3626) www.demco-products.com Go online to www.demco-products.com for Demco warranty policies, product registration & operator manuals.
