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  1. Drain the coolant by removing one of the lower coolant hoses from the motor. Be sure to use a few drain pans under the sled to catch the pilling coolant. A Mity-Vac style suction drain works great to remove coolant without spilling  
  2. Remove the rear coolant hose and the smaller coolant hose near the oil tank. Remove the spark plug wires and remove the spark plugs from the head. Unplug the coolant temp sensor out of the center of the factory head. Remove temp sensor  
  3. Loosen the bolt to the knock sensor and remove it from the head as well   
  4. You can now start loosening and removing the head bolts. Remove head from the engine  
  5. You reuse the base gasket and O-ring cylinder gaskets or purchase new ones from your local dealer if you choose to do so. If your sled has ever overheated, it is best to replace the gaskets then.  
  6.  Install the O-rings in your kit over the spark plug openings of the domes. Install the domes into the billet headcover. The direction of the domes does not matter. You are now ready to install the BMP Billet head on the engine.  
  7. Lightly grease the factory O-rings in the grove of the cylinders. Place the BMP head on the engine. A trick is to put a set of spark plugs into the domes as it makes it easier to set the head on without the domes falling out. Make sure the O-rings are still in place and did not move or get pinched.  You can use a tiny bit of “The right stuff” grey sealer on the bottom of each head bolt. Install and hand tighten bolts. Using a calibrated torque wrench, torque the head bolts in a criss-cross pattern to 25ft-lbs.  
  8. Reconnect the coolant hose in the rear of the head and the smaller hose on the right side of the head near the oil tank. Screw-in and tighten the coolant temp sensor as well as the knock sensor and torque that to 168in-lbs. Tighten new BPR9ES spark plugs into the head domes 18-22ft-lbs.  
  9. Fill sled with 50/50 coolant mix. Start the sled and add coolant as necessary until it maintains coolant in the overflow tank. Let sled warm up to 105 degrees to ensure the T-stat has opened. Recheck coolant in the tank and you are now ready to ride  
  10. Be sure to always use at least 91 premium pump gas with your domes. If you have our race gas domes be sure to always use race gas. To find your dome size you can see the CC stamped into the top of the dome
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