MN-634 (05609) ECR 5791 Pneumatic Control System Kit No. 27225 Please read these instructions completely before proceeding with installation Failure to read these instructions can result in mis-installation Vehicle Requirements... 1 Important Information... 1 Installing the Air Tank... 2 Installing the Height Control Valve... 3 Installing the Compressor and Fittings... 4 *Kit Installation Diagram... 5 Routing the Air Lines... 7 Compressor Wiring... 8 Maintenance Guidelines Adjusting the Height Control Valve... 9 Systems Check... 10 by Thank you for purchasing Air Lift Products Mailing Address: Street Address: AIR LIFT COMPANY AIR LIFT COMPANY P.O. Box 80167 2727 Snow Rd. Lansing, MI 48908-0167 Lansing, MI 48917 Local Phone: (517) 322-2144 Fax: (517) 322-0240 For Technical Assistance call 1-800-248-0892 The Choice of the Professional Installer www.airliftcompany.com
Vehicle Requirements Systems Check Gross Vehicle Weight Rating (GVWR) IMPORTANT: The installation of this kit does not alter the GVWR or payload of the vehicle. Check your vehicle s owner s manual and do not exceed the maximum load listed for your vehicle. Gross Vehicle Weight Rating - The maximum allowable weight of the fully loaded vehicle (including passengers and cargo). This number - along with other weight limits, as well as tire, rim size and inflation pressure data - is shown on the vehicle s Safety Compliance Certification Label. CAUTION: Keep everyone clear of the chassis for the following steps. 1. With everything clear of the chassis, turn the key on and turn the switch on to cycle the system. 5. Check for leaks one more time and fix if necessary. Make sure all the air and electrical lines have been secured. 6. Drain the tank periodically by opening the valve on the bottom. Important Information This control system, whether used for single or dual automatic kneeling, is intended for vehicles that require a kneeling function (ie., ambulances, catering vehicles, flat bed accessibility, etc.). Payload - The combined, maximum allowable weight of cargo and pasengers that the truck is designed to carry. It is GVWR minus the Base Curb Weight. This manual covers the installation of the components and specific installations of components used in conjunction with Air Lift RoadTamer products where applicable. If no specifications are given for the application that you are using, these instructions can be used as a guide for the mentioned components. Call Air Lift at (800) 248-0892 with any further questions. 2. Let the suspension drop to the floor. Check the HCV arms for binding or interference problems. 3. Turn the switch off and check to see that the suspension returns to the ride height determined earlier. NOTE: There is a delay set into the height control valve. It may take 5 to 15 seconds for the valve to open and the suspension to begin raising. 4. Drive around the parking lot or block. Check the height and make any final adjustments if necessary. IMPORTANT: The most important installation step is to leak check the entire system after installation. The number one cause for a premature failure is an air leak which causes unnecessary cycling of the system and increased wear on the compressor. 7. Check for leaks using a solution made up of 1 tablespoon of dish detergent per 16 ounces of water. Spray all fittings on the system checking for leaks. Correct any existing problems. Continue to test and fix the system until no leaks are found. Maintenance Guidelines 1
Adjusting the HCV Valve Installing the Air Tank Maintenance Guidelines 1. Measure the length of the air springs and compare this to the required height specified in the air suspension installation manual. 2. If the air springs are not at the proper length, this can be adjusted by either adjusting the length of the linkage, or by slightly repositioning the height control valve arm. 3. To adjust the height control valve arm, loosen the nylock nut that secures it and slightly rotate the arm up or down to adjust the spring length. NOTE: The height control valve has an 8-10 second delay built in before it reacts to changes. Make small adjustments to the linkages and height control valve arm until the air spring is at the proper length. CAUTION: Failure to adjust the air spring to the proper designed height may cause drive line problems such as vibration and premature wear of the U-joints. 1. Select a ridgid mounting location for the air tank. Use the air tank mounting holes to determine mounting hole locations. Drill four 3/8 diameter holes and secure using bolts (KK), washers (LL), and nylock nuts (NN) (Figure 1). NOTE: Apply thread sealant to all fittings which are not already pre-coated with sealant. 2. No matter which direction the tank is mounted, use the hole at the bottom of the tank for the drain valve. Using a 1/2 to 1/4 reducer bushing (RR), attach the drain valve (R) to the tank. 3. Attach two 1/2 to 1/8 reducer bushings (PP) to two of the four ports on the side of the tank. Connect two 90, 1/8 elbows (F) to the reducer bushings. Axle Figure 1 Always Facing Upward TT T 4. Attach a 3/8 to 1/2 90 elbow (UU) directly onto the tank. This will be the connection for the compressor. 5. For the pressure switch assembly, install a tank valve (TT) to one end of a street tee (SS). Attach a pressure switch (T) to the top of the street tee (Figure 2). 6. Attach a 1/2 to 1/8 reducer bushing (PP) to the end of the tank and attach the pressure switch assembly to the bushing (Figure 2). 7. Plug the open port or ports on the tank using the provided plugs (QQ). UU QQ RR F C PP SS NN LL RR R PP NN QQ LL Figure 2 KK Always Facing Downward 9 2 KK
Installing the Height Control Valve Compressor Wiring NOTE: When installing the height control valve, first review the instructions included with the valve and the following figures to become more familiar with the mounting geometry and hardware. Figure 3 Ring Terminal Ring Terminal Height Control Valve Link Tab Washer NOTE: The air lines must be attached to specific ports dependant on the orientation of the height control valve. The air supply line must always be attached to the port that is at the bottom of the control valve. The line going to the air springs must be in the middle and the exhaust line is always attached to the port at the top. 1. Mount the height control valve (M) to the frame using two 1/4 hex cap screws (J), four flat washers (K), and two 1/4 nyloc nuts (L) (Figure 6). 2. Bring the vehicle to the designed ride height per the suspension installation instructions. Refer to the information provided with the suspension kit to set the suspension and air spring to the proper position. This may be accomplished by either blocking up the frame of the vehicle, or using air pressure in the air springs to bring the vehicle to the proper height. 3. Move the control arm on the height control valve to a 45 down position for 10-15 seconds to calibrate the valve. Return the control arm slowly to the center position. Insert the wood location pin in to the adjusting block bracket on the valve. NOTE: This procedure is setting the delay of the valve. If this procedure is not performed, reduced performance in the control system will result. 4. The valve link has to go from the height control valve arm, down to the beam, and attach to the height control valve link tab (Figure 4). Assemble the arm so that it is the proper length. 5. Loosely attach the link to the height control valve using the supplied 1/4 hardware. Attach the control valve link tab to the opposite end. 1. Connect the male spade on the red compressor wire to the female terminal on the 12 gauge red wire. 2. Connect the other end of the 12 gauge red wire to one of the terminals of the pressure switch using 12 gauge wire and one 1/4 female spade terminal (Figure 9). 3. Assemble the power wire using 12 gauge wire, terminals, butt connector, fuse and fuse holder or equivalent (Figure 10). 4. Connect this assembly to a 30 AMP keyed power source (Figure 10). 5. Let the compressor run to fill the tank. Terminal 30 Amp Keyed Relay 30A A Figure 9 Figure 10 12 Gauge Wire Ground 30 Amp Fuse or Equivalent +12V Washer Height Control Valve Link Tab 6. Set the link tab onto the beam, mark the holes and centerpunch the beam. Drill a small pilot hole so that the self-tapping screw can be inserted easily. 3 Figure 4 8
Routing the Air Lines Installing the Height Control Valve (Cont.) 1. Continue to route and plumb the system according to Figure 6. NOTE: A clean square cut will ensure against leaks (Figure 7). Air Line Cutting Good Cut Poor Cut 2. Attach the height control valve fittings to the height control valve. 3. Attach the air lines from the height control valves to the tank using the supplied 1/2-1/8 (PP) bushings and 1/8 x 1/4 elbow fittings (F). Figure 7 Figure 8 Cut off excess air line squarely. Install the air line into the fitting. This is a self locking fitting. Push and slightly turn the cut end of the air line into the fitting as far as it will go. You will hear or feel a definite click when the air line is seated. Air line should go in 9 /16". The air line is now installed. 7. Remove the valve link tab from the valve link and attach it to the beam using the provided self-tapping screw. 8. Adjust the length of the link (N) and secure using the supplied screws and nuts. Install the plastic fitting to the top ports(s) on the height control valve. Attach the clear plastic hose to this fitting. Ensure that the holes of the link line up with the height control valve and the height control valve bracket on the beam. Secure the link using the supplied 1/4 hardware. Installing the Compressor and Fittings 1. Select a rigid convenient mounting location under the hood or in a storage area. NOTE: The location selected should shield the compressor from the elements and heat sources. 2. Attach the provided check valve (D) and air fitting (OO) onto the leader hose on the compressor. Tighten finger-tight plus 1 1/2 turns. Do not overtighten. NOTE: Do not tighten bolts on the links tight. They must be loose enough to be able to turn by hand. If they are too tight, premature failure of the bushing will result. NOTE: Fine adjustments in ride height can be made by loosening the height control arm nut and rotating the control arm. 9. Remove the wooden locating pin. 10.The height control valve will be fine adjusted after the system is fully installed and functional. Refer to page 9, Adjusting the Height Control Valve. 3. Using the holes in the base of the compressor as a template, mark and center-punch the four holes. Drill the holes out to 3/16 diameter. 4. Position the compressor over the mounting holes and secure with the supplied hardware. D Q OO A Figure 5 Ground 7 4
Kit Diagram Kit Diagram Figure 6 Item Part No. Description Quantity A 16380 Compressor 1 B 10632 Link Bracket 2 C 24290 Pressure Relief Valve 1 D 21760 Check Valve 1 F 21744 1/4 x 1/8 90 Elbow 2 G 21640 1/4 Weather Head Union Tee 3 J 17174 1/4-20 x 1.25 Hex Cap Screw 8 K 18419 #12 Flat Washer 16 L 18425 1/4-20 Nyloc Nut 8 M 25526 Height Control Valve 2 Hardware List Item Part No. Description Quantity N 10547 Height Control Valve Link 2 O 10991 Air Tank 1 P none 1/4 Diameter Hose supplied by customer Q 20947 3/8 Diameter Hose 15 R 21944 Cable Pull Drain Valve 1 T 24551 110-145 PSI Pressure Switch 1 U 26394 Two-Way Solenoid Assembly 1 V 26397 Three-Way Solenoid Assembly 2 Z 24595 Female Terminal 2 KK 17159 3/8-16 x 1.5 Bolt 4 Item Part No. Description Quantity LL 18444 3/8 Flat Washer 4 NN 18435 3/8-16 Nyloc Nut 4 OO 21862 1/4 MNPT - 3/8 Connector 1 PP 21251 1/2 MNPT to 1/8 FNPT 2 QQ 21193 1/2 Hex Head Plug 3 RR 21247 1/2 MNPT - 1/4 FNPT Reducer 2 SS 21740 1/8 MNPT x 1/8 FNPT Street Tee 1 UU 21747 3/8 x 1/2 Swivel Elbow 1 VV 17173 Self-Tapping Screw 2 WW 21633 Push Lock Valve 3 (2 from 39216 kit) XX 26065 Low Pressure Sensor 2 YY 24574 Warning Lamp 1 5 6