Attention: TDR Forum Junkies 
I thought I would share some pics and info from my winter project. I got a 1985 M998 HMMWV in a trade for another military truck. Problem was, the 6. 2L diesel was a rusty, locked up boat anchor. So, with dreams of a Cummins Humvee dancing in my head, I made a trip to OH and picked up a 1995 190hp Cummins 6BT from a Ford bus. The engine test fired just fine, so I went about readying the HMMWV for the transplant. Then, somewhere along the way, the wife ends up pregnant with our second son. I got a little worried about having a dead humvee in the garage all winter with my wife trudging through the snow with two kids to get to her SUV so I put the Cummins swap on hold in favor of throwing in another 6. 2L. I assumed that would be a lot faster, but that 6. 2L turned out to have a bad pump and a couple of leaky injectors. Rather than dump any more money in it, I yanked it out after the baby was born. My wife was just tickled 
I pulled the 5. 9L out of the back of the garage and dusted it off. I swapped the huge front-sump pan out for a Dodge rear-sump. Then, I pulled the timing cover, tabbed the dowel pin and replaced the crank seal. I purchased an adapter from fordcummins.com and bolted that in place. After that, I had to lift the front of the HMMWV body about 18" to make room for the engine to clear the body and frame. Once I wiggled the engine into place, I could lower the body and check for clearance issues. With the trans in the stock position, the crank dampener was hitting the front crossmember and differential mount. I decided to slide the whole engine and drivetrain back 3" rather than hack a hole in the crossmember. That actually worked out really well because it distributed the weight more evenly and allowed me to sit the engine lower between the frame-rails to keep the center of gravity low. I went to work on fabbing some engine mounts once I had the engine sitting where I wanted it. I used cardboard to make some templates and then cut pieces out of 3/8 x 4" plate. I tacked them together, bolted everything up, checked the engine position, removed them and welded them solid.
Once the engine was in I had to cut and section the water inlet because it was hitting the frame. I shortened it and tightened the radius to get it to clear. After that, I got the radiator bolted in and hooked my hoses up. I cut and spliced an upper hose from a chevy diesel to make my top hose. I am going to weld one up out of steel tubing to make it look more factory. At this point I was getting very eager to start it so I started working on the fuel system. I ran rubber lines to the pick-up and return fittings on the tank. I left the stock lift pump in place as it was working well when we test fired it. Next, I used a shut-off cable from a M35A2 6x6 to make a manual shut-off for the injection pump. I ditched the sloppy factory throttle pedal/linkage in favor of a Lokar aluminum pedal and braided stainless throttle cable.
Next, I had to tackle the electrical system. I used the stock humvee sending units in the Cummins to make the gauges work, sourced a 24v alternator that would fit in the Ford factory mount and wired the stock starter switch to operate the Ford 6. 0L starter. Why a 6. 0L starter you ask? Because that's what the fordcummins.com guys used with their adapter and billet flywheel. Nobody makes or custom winds a 6. 0L starter in 24v so I am starting on 12v and running everything else on 24v. I am just center tapping the pair of batteries for now, but will add a third battery and a 24-12v battery equalizer in the near future for starting and other 12v accessories.
Finally, I was ready for a test fire. I primed the pump until the button was firm and then flipped the switch. It fired and ran after about 6 revs.
Once it actually ran I had to fab the intercooler mount, install the intercooler, run intercooler piping, install trans cooler, fab transmission/t-case shifter, run trans lines, fab/install 2. 5" body lift, fab a downpipe/cross-over, install hood, install seats/windshields/top/doors, install Dodge vacuum/PS pump, install a new hydroboost unit, install 24v LED headlights/taillights, fab electric fan mount, and install 24v fan/thermo.
I still have to install Westach boost/egt gauge, install mirrors, mount 37x12. 50R16. 50 Baja TA's on my 24-bolt beadlock rims, fab a new trans x-member, install late-model parking brake kit, install 3-point seatbelt kit, install trans kickdown switch and fab a new engine cover.
Phew! What a project. Here are some pics!
I pulled the 5. 9L out of the back of the garage and dusted it off. I swapped the huge front-sump pan out for a Dodge rear-sump. Then, I pulled the timing cover, tabbed the dowel pin and replaced the crank seal. I purchased an adapter from fordcummins.com and bolted that in place. After that, I had to lift the front of the HMMWV body about 18" to make room for the engine to clear the body and frame. Once I wiggled the engine into place, I could lower the body and check for clearance issues. With the trans in the stock position, the crank dampener was hitting the front crossmember and differential mount. I decided to slide the whole engine and drivetrain back 3" rather than hack a hole in the crossmember. That actually worked out really well because it distributed the weight more evenly and allowed me to sit the engine lower between the frame-rails to keep the center of gravity low. I went to work on fabbing some engine mounts once I had the engine sitting where I wanted it. I used cardboard to make some templates and then cut pieces out of 3/8 x 4" plate. I tacked them together, bolted everything up, checked the engine position, removed them and welded them solid.
Once the engine was in I had to cut and section the water inlet because it was hitting the frame. I shortened it and tightened the radius to get it to clear. After that, I got the radiator bolted in and hooked my hoses up. I cut and spliced an upper hose from a chevy diesel to make my top hose. I am going to weld one up out of steel tubing to make it look more factory. At this point I was getting very eager to start it so I started working on the fuel system. I ran rubber lines to the pick-up and return fittings on the tank. I left the stock lift pump in place as it was working well when we test fired it. Next, I used a shut-off cable from a M35A2 6x6 to make a manual shut-off for the injection pump. I ditched the sloppy factory throttle pedal/linkage in favor of a Lokar aluminum pedal and braided stainless throttle cable.
Next, I had to tackle the electrical system. I used the stock humvee sending units in the Cummins to make the gauges work, sourced a 24v alternator that would fit in the Ford factory mount and wired the stock starter switch to operate the Ford 6. 0L starter. Why a 6. 0L starter you ask? Because that's what the fordcummins.com guys used with their adapter and billet flywheel. Nobody makes or custom winds a 6. 0L starter in 24v so I am starting on 12v and running everything else on 24v. I am just center tapping the pair of batteries for now, but will add a third battery and a 24-12v battery equalizer in the near future for starting and other 12v accessories.
Finally, I was ready for a test fire. I primed the pump until the button was firm and then flipped the switch. It fired and ran after about 6 revs.
Once it actually ran I had to fab the intercooler mount, install the intercooler, run intercooler piping, install trans cooler, fab transmission/t-case shifter, run trans lines, fab/install 2. 5" body lift, fab a downpipe/cross-over, install hood, install seats/windshields/top/doors, install Dodge vacuum/PS pump, install a new hydroboost unit, install 24v LED headlights/taillights, fab electric fan mount, and install 24v fan/thermo.
I still have to install Westach boost/egt gauge, install mirrors, mount 37x12. 50R16. 50 Baja TA's on my 24-bolt beadlock rims, fab a new trans x-member, install late-model parking brake kit, install 3-point seatbelt kit, install trans kickdown switch and fab a new engine cover.
Phew! What a project. Here are some pics!
! 
