My Snout bearing went out on my 03 Cobra stock eaton super charger, so I had 2 options have someone do the repair or repair it myself.
After reading Posi's home port thread I decided I would do a home port and replace the bearings while I was at it.
As most probably know when removing the Innercooler from the Super Charger it's likely you will break at least one bolt, which is exactly what happened in my case.
So I decided I would try to drill the bolt out myself. Since I've really never drilled a bolt out of anything I did my research and thought left handed drill bits would be the first attack to getting the broken innercooler bolt out of the super charger. With limited knowledge I bought a set of left handed drill bits from Autozone titanium coated. I took a punch and marked the spot on the bolt to drill down center. Needless to say the left titanium bit did not make a scratch on the bolt and the drill bit and eventually broke.
Again lacking knowledge I bought another heavy duty drill bit and again it broke. After breaking a few drill bits I returned to the internet for research. As it turns out to my ignorance these bolts are hardened steel bolts actually class 10.9 to be exact. I tried cobalt drill bits again they barely scratched the surface of the bolt. Through much research I learned carbide drill bits are the best for drilling through hardened steel.
So I purchased 2 carbide drill bits from toolguys2 from ebay one being a straight flute and the other a standard twist type. Toolguys2 were not too far from where I lived so I picked the drill bits up in person, these guys were great and gave great service. They really couldn't believe that was drilling the bolt out using a hand drill but they told me to use low rpms and some type of lubricant. Note Carbide bits are strong for drilling through hardened steel but they are very brittle and if binded or twisted at an angle break easily like glass. If you break a carbide bit off in a hole, lets just say your screwed.
I used low rpms and transmission fluid Type F as a cutting lubricant, and needless to say it cut through the bolt like butter.
Once I drilled the bolt out I decided I would use a tap to remove some of the remains of the bolt, sadly to say I never really used a tap before and next thing I knew I broke the tap off in the hole. At this point I'm having an out of body experience.
I called a machine shop and asked could they remove the broken tap, they basically told me good luck, nobody wants to deal with a broken tap, because you can't drill through them. Even when I tried the carbide bit it just rounded the bit off.
After many hours of research I discovered there are chemical means to removing broken taps from aluminum. Nitric Acid, which is not recommended due to cost and hazard and Alum which is used to make pickles. Yeah Pickles.
It turns out Alum when diluted heavily with water and especially heated will dissolve ferrous metals and not harm non-ferrous metals (i.e. aluminum).
After adding the Alum and water solution to the hole 2 times a day sometimes heating it with a torch and sometimes using a halogen light to heat it, the BROKEN TAP DISSOLVED. Incredible.
I was able to drill the hole out, tap it, and insert a helicoil to allow me to use the OEM bolts. By the way I ordered new stronger bolts.
And I lived happily ever after.
I hope this helps somebody if I had any of this knowledge I would have saved me a ton of time and heart ache.
After reading Posi's home port thread I decided I would do a home port and replace the bearings while I was at it.
As most probably know when removing the Innercooler from the Super Charger it's likely you will break at least one bolt, which is exactly what happened in my case.
So I decided I would try to drill the bolt out myself. Since I've really never drilled a bolt out of anything I did my research and thought left handed drill bits would be the first attack to getting the broken innercooler bolt out of the super charger. With limited knowledge I bought a set of left handed drill bits from Autozone titanium coated. I took a punch and marked the spot on the bolt to drill down center. Needless to say the left titanium bit did not make a scratch on the bolt and the drill bit and eventually broke.
Again lacking knowledge I bought another heavy duty drill bit and again it broke. After breaking a few drill bits I returned to the internet for research. As it turns out to my ignorance these bolts are hardened steel bolts actually class 10.9 to be exact. I tried cobalt drill bits again they barely scratched the surface of the bolt. Through much research I learned carbide drill bits are the best for drilling through hardened steel.
So I purchased 2 carbide drill bits from toolguys2 from ebay one being a straight flute and the other a standard twist type. Toolguys2 were not too far from where I lived so I picked the drill bits up in person, these guys were great and gave great service. They really couldn't believe that was drilling the bolt out using a hand drill but they told me to use low rpms and some type of lubricant. Note Carbide bits are strong for drilling through hardened steel but they are very brittle and if binded or twisted at an angle break easily like glass. If you break a carbide bit off in a hole, lets just say your screwed.
I used low rpms and transmission fluid Type F as a cutting lubricant, and needless to say it cut through the bolt like butter.
Once I drilled the bolt out I decided I would use a tap to remove some of the remains of the bolt, sadly to say I never really used a tap before and next thing I knew I broke the tap off in the hole. At this point I'm having an out of body experience.
I called a machine shop and asked could they remove the broken tap, they basically told me good luck, nobody wants to deal with a broken tap, because you can't drill through them. Even when I tried the carbide bit it just rounded the bit off.
After many hours of research I discovered there are chemical means to removing broken taps from aluminum. Nitric Acid, which is not recommended due to cost and hazard and Alum which is used to make pickles. Yeah Pickles.
It turns out Alum when diluted heavily with water and especially heated will dissolve ferrous metals and not harm non-ferrous metals (i.e. aluminum).
After adding the Alum and water solution to the hole 2 times a day sometimes heating it with a torch and sometimes using a halogen light to heat it, the BROKEN TAP DISSOLVED. Incredible.
I was able to drill the hole out, tap it, and insert a helicoil to allow me to use the OEM bolts. By the way I ordered new stronger bolts.
And I lived happily ever after.
I hope this helps somebody if I had any of this knowledge I would have saved me a ton of time and heart ache.
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