Engine/Transmission (1998.5 - 2002) AFS Big Dog Fuel system and Draw Straw Install

[MBFARMS]

I installed an AFS Big Dog Fuel system and Draw Straw on a friends truck last night and took pictures. The install was very easy and we ended up with some good fuel pressure numbers. At idle it is about 16 PSI and WOT it will drop about 1/2 a pound. We adjusted the regulator to get these pressures. After you get the module out cut the pick tube and this should allow the module to drop. Take the module part and unhook the fuel float module wire. Take the fuel pickup assembly out and remove the supply fitting from the top of the module. Take the bottom fuel puck off. There will be a top screen there. Take a razor blade or sharp object and cut the screen out. Make sure to remove only the top one. Drill the hole large enough for the draw straw to fit through and drill two holes to the side of it( see pictures in the next post). Put the puck back on, put the module back together and plug the float module back up.

 

[MBFARMS]

These are all pictures of the draw straw install. Check out the small line and all the restriction in the module.

 

[jkalchik]

I'll ad that you want to be *VERY* careful that you don't puncture the fragile screen in the bottom of the module when installing Vulcan's Draw Straw. Don't ask me how I know this.....

 

[MBFARMS]

Next I inserted the Module back in the tank, put the draw straw in place( be sure the module is all the way to the bottom and the Draw straw tube is inserted into the hole properly), and make measurement. Cut off the appropiate amount of hose( be sure to cut at a slight angle). Pull the module up a little and put the draw straw in the groment( make sure the tube is in the proper place) and kinda hold the bottom part of the module up against draw straw and slide the module back in the tank. Put the lock ring on and tighten.

 

[MBFARMS]

While I had the tank down I took the factory supply line out. Remove the banjp bolt from the rear of the Fuel Filter housing. Uplug the factory lfit pump from the factory harness. Take the three bolts off the top of the lift pump and remove lift pump. Take the 90* elbow with the 12mm adapter and washer and swivel pushloc and push the 3/8 hose up on the push loc( remember to lube fitting and apply a little heat to hose). Feed the hose behind the filter housing and down to the frame. Install 12mm fitting( do not over tighten). Install 90* elbow and pushloc. Take the bolt out of the line mount above the tranfercase cross member. Take the mounting bracket supplied and slide the shorter end up under the line bracket. Install Line Bracket bolt. Put your pump in the pump clamps and install them to the bracket, remembering to point the regulator down so the return line runs under the bracket. Cut your hose from the fuel filter to length. Get the relay harness incleded in the kit and feed the pump wires down to the frame rail( make sure it is out of the way of the steering). Run the trigger wire over to the factory connector. Use the velcro strip to secure the fusable link and connect the negative postition to the negative post on the battery. No not hook up the positive yet. Run the pump wires down the frame rail and ziptie the hose and wire. Connect the pump wires to the pump. Cut a small peice of hose. Take and install the hose on the out side pushloc of the fuel filter. Install the other end of the hose on the inlet to the pump and install clamp. Measure the length of hose needed for the supply line and cut. Install the hose on the supply side of the draw straw. Install pushloc swivel end of the supply line. Cut about 4" out of the middle of the filler vent tube and install the return tee and clamps. Measure the length of hose from the return off the pump to the return tee and cut. Install the puchloc swivel on the return side and install the other end to the return tee and install clamp. Remove the plastic from the stock fuel return line, so you only have steel line showing. Measure and cut the 5/16 line that came with the draw straw. Install the line on the pushloc on the draw straw and attach other end to the steel return line and install clamp. Push tank back in place and secure. Install module wire and install hoses. Attach the supply line to the fuel filter. Connect the positive wire of the relay to the battery. Bump the starter( do not start). You may have to do this a few things to bleed the system. Check for any leaks. Start the truck. Check your fuel pressure.

 

[MBFARMS]

Hope this helps someone out.