"McRat" Turbo Install Instructions

 

 

  • Prepare all required tools and lay a large white bed sheet out on the work table. To keep track of parts taken off, I lay them on the sheet and label the parts directly on the sheet with a permanent marker. Inspect all included parts and check to make sure all required parts are present before beginning. Be sure to read through instructions thoroughly before beginning so you have all required extra supplies/tools before disabling truck!
  • disconnect both batteries

  • insert a ½” breaker bar into the serpentine belt tensioner to release tension on the serpentine belt. Remove the belt.

  • unplug the two electrical connectors near the air conditioning compressor. Unbolt the 4 large bolts that hold the AC compressor to the engine.

  • carefully swing the AC compressor up and over the engine, and lay it upside down on the passenger side battery, as shown in the picture. Be careful not to stress the AC lines.

  • Remove the air intake tube. The pictures shown are with an AFE Stage 2 aftermarket intake, but other aftermarket intakes should be similar. There is no need to remove the actual airbox itself, just the tube that connects the airbox to the inlet of the turbo.

  • If the large “6.6 turbo diesel” box/resonator is still on the engine, remove it as it is not needed. You will need a 2 ½” plumber’s rubber end cap to cover the hole in the turbo inlet plastic “Y” pipe. Also remove the PCV hose inlet at this time.

  • loosen the large hose clamp that holds the plastic “Y” pipe onto the inducer/inlet of the turbo. Remove the plastic “Y” pipe and set it aside. You may need to move some wiring harnesses aside to remove it.
  • Remove the heat shield covering the top of the turbo

  • remove the rubber boots that connect the turbo to the intercooler pipes and remove the rubber boot connecting the passenger side intercooler pipe to the intake manifold. Stuff rags into the intercooler pipes to assure nothing will fall into the intercooler.

  • Remove the intake manifold by loosening the bolts shown.

  • Unbolt the long silver tube (EGR cooler) from the back of the EGR motor housing and from the rear EGR up-pipe manifold, back by the firewall, where EGR blocker plates fit in. Move the EGR cooler tube to the side.

  • Unplug the EGR and unbolt the cast EGR motor housing from the engine.

  • Remove the intake tube that goes down in the engine. There are no bolts holding it in; it is sealed by two O-rings and held in place by the intake manifold. It is tricky to squeeze the tube out so take your time. Stuff a towel or tape in the intake tube hole to assure that no bolts or debris will fall into the engine intake.

  • remove the passenger side PCV fitting, located on the valve cover as shown. Loosen the bolt and swing the PCV tube assembly off to the driver side so it is out of the way. Tape over the passenger side PCV hole to be sure nothing falls in.

  • Remove the glow plug control module, located on the driver side of the engine back near the firewall, next to the turbo and behind the silver intercooler tube. There are two bolts holding it in place. Do not unplug it, just swing it off to the side.

  • Loosen the large v-band clamp that holds the downpipe on the exhaust outlet of the turbo.

  • crawl under truck and remove front pipe and/or catalytic converter. Exhaust system from the 4-bolt flange back does not have to be removed and can be left in place.
  • jack truck up and remove both front wheels and plastic fender linings. Support truck by the frame with sufficient jack stands. Do not rely on a jack alone to hold the truck up!
  • remove the two bolts that hold the dipstick to the engine/transmission bellhousing. Pull dipstick out of transmission and stuff a rag into the hole to prevent transmission fluid from leaking out.

  • remove clamp that holds the stock downpipe to the passenger side exhaust manifold. Remove the aluminum heat shield that covers the downpipe and slide the downpipe out from behind the engine through the passenger side wheel well

  • remove the passenger side up-pipe bolts with a 12mm 12-point socket. You may need to use PB Blaster or Liquid Wrench to loosen the bolts, as they may be tight. There are 3 bolts that hold the up-pipe to the passenger side exhaust manifold and 3 that hold it to the pedestal of the turbo. If the bolts are extremely tight, it is possible to use a long ratchet handle and “cheater pipe” to give more leverage on the bolts. Slide the passenger side up-pipe out.

  • still through the passenger side wheel well, loosen the top driver side up-pipe bolts. Go around to the other side of the truck and loosen the lower driver side up-pipe bolts that hold the driver side up-pipe to the driver side exhaust manifold. Slide the driver side up-pipe down. You may need to remove the driver side up-pipe heat shield to slide the up-pipe down. You do not need to fully remove the driver side up-pipe, just move it down enough to access the rear oil drain of the turbo.

  • Loosen the coolant surge tank cap to reduce possible vacuum in the cooling system. Drain the coolant from the engine from the radiator drain plug located in the passenger side wheel well at the base of the radiator. Do not pull the plug completely out! If you pull it completely out, the coolant will rush out with such force that it will spray all over the wheel well and make a mess. Drain all of the coolant into a large clean bucket.
  • On the top of the turbo, disconnect the oil feed hose and banjo bolt. Also disconnect/unscrew the vane position sensor and unplug the vane position control solenoid plug.

  • disconnect the coolant inlet and outlet hoses from the turbo. Some coolant will still be in the system so be sure to stuff a rag under the connections when you disconnect the hoses. There are banjo bolts connecting the tubes to the turbo, but I just cut the hose with a knife, as it is not needed anymore because the McRat turbo is not cooled with coolant.
  • cut the coolant hoses going in and out of the EGR cooler. I “crimped” the hose coming out of the heater core/into the EGR cooler (two coolant hoses that go through the firewall) with Vice Grips to prevent the coolant from draining from the heater core. Grab a small plastic container, loosen the Vice Grips, and allow the coolant to drain. Remove the EGR cooler completely from the engine and set it aside, as it will not be used anymore.

 

  • Using two lengths of 5/8” heater hose, bypass the coolant fittings/tubes that passed through the stock turbo as shown. Use small pipe clamps to be sure the hoses are secure.

  • Reach behind the turbo and loosen the 2 12mm bolts that hold the turbo oil drain tube to the rear cover of the engine. I found it easiest to loosen the bolts from the passenger side wheel well, but it is possible to reach the bolts from the top of the engine as well.

 

  • Using a long 3/8”-drive ratchet extension and 17mm swivel-joint socket as shown, loosen the 3 17mm bolts that hold the turbo pedestal to the engine block (circled in red). They are hard to get to but the swivel-joint socket makes this much easier. After loosening the bolts, you can use a long magnetic pick-up tool to retrieve them, as it is hard to reach your hands in.

  • Look over the turbo and jiggle it to be sure it is completely disconnected from the engine. Reach behind the turbo and pull the oil drain tube straight up so it is stuck not on the threaded studs. Be careful not to strip the small studs.

  • Grab hold of the turbo and lift it out. I found it easiest to stand “on top” of the engine with one foot on the large AC compressor holding cradle/bracket.
  • Remove the braided-steel turbo oil feed hose banjo bolt from the engine block by carefully unscrewing it.
  • Look into the oil feed hole and spin the engine over by hand. Observe the #4 cam bearing and if the bearing is spun, the engine must be replaced.

  • screw in the new oil feed hose and fitting that is provided in the turbo kit. Do not use any pipe thread tape!
  • Assemble the McRat turbo and pedestal on the bench: screw the 4 studs into the pedestal as shown, be sure not to forget the metal gasket. Double nut the studs as shown to make sure the studs are tight in the pedestal. Once all the studs are tight in the pedestal, install the turbo onto the pedestal and tighten the 4 nuts that hold the turbo to the pedestal. Install the 2 provided studs into the oil drain flange on the turbo. Tighten the studs using the “double nut” method. Place one gasket over the studs into the turbo oil drain flange. Then place the oil drain spacer on the studs, followed by a second gasket, followed by the new provided oil drain tube and nuts. Tighten the nuts and be sure not to bend or stress the oil drain tube. Install the larger gasket on the rear cover of the engine over the studs. Be sure the surface is clean and there are no remnants of the old gasket on the engine block/rear cover. The new oil drain tube is required because the McRat turbo sits ~1” farther towards the rear of the engine than a stock LLY turbo.

  • carefully pick up the turbo and install it in place on the engine. Be sure to align and slide the oil drain tube over the studs on the rear cover of the engine before you set the turbo down fully. Reach under the turbo and slide the aluminum heat shield around so the main turbo-to-block mounting bolt holes line up. Install the 3 17mm turbo mounting bolts with the swivel socket and tighten to ~80 ft. lbs. Reach behind the turbo and tighten the two bolts that hold the oil drain tube to the rear cover of the engine.

  • Test fit the new downpipe and see if it hits the firewall. If it hits the firewall or does not fit, it may be necessary to “adjust” the firewall with a hammer or pry bar. You will also have to grind off one of the mounting studs on the firewall. After adjustments are made and the downpipe fits, use some black spray paint to cover any areas that might have had paint chipped off where the pry bar/hammer contacted the firewall. This is just to prevent any bare metal/areas for rust. Be sure there is also sufficient room so the downpipe does not vibrate against the firewall.

  • remove the downpipe and install the up-pipes, be sure to orient the crush-metal gaskets correctly and use good amounts of Anti-Seize on the bolts. Tighten bolts and check to make sure they fit properly and do not rub on anything. NOTE: LLY trucks have the EGR pipe/fitting on the passenger side up-pipe. You must cut off the EGR pipe fitting and weld a plate flush in place of the EGR rise. The other alternative is to buy a factory LB7 passenger side up-pipe; as LB7’s do not have the EGR riser on the up-pipe. If you chose to weld the stock LLY pipe, be sure it is completely air tight.

  • Install the new dipstick tube provided with the kit. It may be necessary to slightly adjust the dipstick to fit easily. When you remove the stock dipstick, stuff a shop rag or something in the hole on the trans so no fluid leaks out. Secure the dipstick with the provided clamp and nut.
  • wrap the downpipe in exhaust-header wrap. Be sure to soak the header wrap in water before hand. That way, when it heats up on the truck, it will shrink and stay tight on the downpipe. Be sure the wrap is on tightly and neatly and secured properly with the clamps.

  • reinstall the downpipe and v-band clamp on the turbo, however do not fully tighten the v-band clamp yet.
  • under the truck, make a note of how long the front-pipe needs to be shortened to fit properly into the new downpipe. Cut the front pipe to the appropriate length and slip it into the new downpipe and secure tightly with the provided exhaust band clamp. Reassemble the rest of the exhaust at this time as well and be sure the exhaust is not sitting on any cross-members or any part of the frame that could cause it to rattle.

  • after checking that the whole exhaust system is secure, tighten the v-band clamp on the turbo.

  • First pour a bit of 10w-40 motor oil into the turbo to pre-lube it, and then attach the oil feed 90-degree fitting onto the oil-inlet on the turbo. It may be necessary to use pipe-thread tape but be sure to wrap the tape in the correct direction and that there are no extra pieces of tape hanging off the end of the 90-degree pipe fitting that could get into the turbo. Attach and tighten the stainless oil feed tube.

  • Connect the intercooler tube to the turbo outlet. NOTE: the LLY factory turbo sits ~1” further forward than the McRat turbo, so it may be necessary to get a slightly longer intercooler boot to get the pipe to line up with the outlet of the turbo compressor. Be sure to orient the spring boot clamp downward as shown so it does not rub on the AC line.

  • slip the main engine intake pipe back into the engine, and be sure the pipe is completely seated and the O-rings are clean as shown.

  • cut out a plate of ¼” steel to fit over the rear inlet of the EGR motor housing. Bolt it to the EGR motor housing and be sure to use RTV or a gasket so it seals tightly. NOTE: I did this at first, but found the EGR motor housing would still leak around the motor-to-casting seal, so I ended up making two small plates out of 1/16” steel that fit on the top of the EGR motor housing in between the EGR motor housing and intake manifold, to effectively completely bypass the EGR motor housing/casting. I sealed it with RTV and it has worked fine. Another alternative is to buy the PPE EGR-delete intake manifold, however it is quite expensive.

 

  • bolt the EGR motor housing onto the engine and be sure to plug the EGR motor connector back in. I found that if I left the EGR motor unplugged, the engine would still throw codes every once in a while.
  • install the intake manifold back onto the engine with the proper gaskets and reconnect the passenger side intercooler tube. NOTE: if you do not already have a boost gauge, you should drill and tap the intake manifold for a boost gauge fitting at this point BEFORE you reinstall the intake manifold on the engine.

  • modify the stock plastic “Y” pipe as shown (grind off the lip on it) and slip the large silicone pipe fitting and secure with a pipe clamp. Slip it onto the inducer of the turbo and tighten both band clamps.

  • reinstall the glow plug control module and PCV hose, unless you are converting to an open PCV system.

  • swing the AC compressor back over the engine and bolt into place. Be sure to reconnect both electrical connectors. Wrap the AC line in thick heater hose where it passes over the turbo as shown. Also using aluminum heat wrap is a good idea; basically anything that will protect the AC line from the heat of the turbo.

  • Reinstall the serpentine belt, be sure to follow the correct belt routing diagram.

  • check over the entire engine for loose bolts, tools left on the engine, loose fittings, dangling wires, and anything else that was removed or changed during the install. NOTE: there will be two wires and connectors left over from the variable vane turbo. I coiled up the vane control wire and tucked it into the wiring harness. If you follow the vane position sensor wire (the white wire) back thru the engine, it connects to another electrical connector. You can unplug it there and remove the entire vane position sensor wiring.
  • reinstall the air intake tube and tighten the pipe clamps

  • refill the engine with coolant. Be sure to ONLY use coolant that is specifically marked “DEX-COOL COMPATIBLE” on the front of the container.
  • reconnect batteries and double check everything one more time!

  • Pull the TBC BATT fuse. This will prevent the engine from starting when you crank it. This is just a precaution to build some oil pressure in the turbo before starting the engine.

  • Crank the engine. It will fire for a split second and stall. Do this several more times. Replace the TBC BATT fuse and start the engine. Do not rev it, just let it idle.
  • Look carefully over the engine for any initial oil or air leaks. CAREFULLY feel around the EGR motor housing and passenger side exhaust up-pipe for any leaks. Check this right after starting the engine; the up-pipe will not be that hot. Be sure to be careful around the cooling fan. Let the engine idle for 5 minutes or so.
  • If no leaks are present and everything looks good, take the truck out for a test drive and observe boost levels, any odd noises, etc…
  • Shut down the truck and check over once again for leaks and anything that might be loose. The coolant level may have gone down slightly as there is probably air in the cooling system. Refill it to the FULL mark.
  • Change the engine oil after 100-200 miles to be sure no dirt got into the oiling system during the install.
  • Enjoy the new turbo!

Ben – duratothemax
The Diesel Place
www.dieselplace.com

 

 

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