NS300L Head Bolt Thread Repair 2015 Silverado L86

[TigerTruck]

 

Tapping the hole, short tap

Edited February 15, 2024 by TigerTruck

[TigerTruck]

 

Tapping the hole, long bit

[TigerTruck]

You can only drill and tap 9 holes. Save the hole #10 in a space that is easy to do. You will have to set the insert next to the last hole to finish the job. Each hole must be oil free. You will need multiple cans of BrakeKleen to clean the holes. Please note: MAKE SURE YOU HAVE GOOD VENTALATION, BRAKEKLEEN STINKS!!!!! I cleaned them this way: start at the upper holes and spray slowly into the hole until the junk coming out clears up. CAREFULLY AND SLOWLY, with a rag covering the hole, blow out the brakekleen. I repeated this at least two more times and the final time used lots of air to dry the hole out. I then spray the insert to make sure it was oil free. The rag will catch most of the brakekeen. Immediately toss the rag outside. The instructions say to screw in an insert to make sure the hole is deep enough. I tried to do this but I got worried that the insert would get stuck because it did not screw in cleanly. I found out that as long as the holes are drilled fully and the holes are tapped fully, the inserts will screw in all the way with the threadlock applied. The threadlock acts as a lubricant and I did not have any real problems screwing in the inserts. I allowed the threadlock to set up for 24 hours but I don’t think it really set up since its so cold in my garage. I do have a heater that I use while working but I turn it off overnight. I reinstalled the head and had no problems with the bolt holes. I did purchase a new digital angle torque wrench from Lowes that made torquing and the final two angle tightening sequences a lot easier. Even still, that one lower head bolt next to the firewall was tough.