In my search for the internal workings of the IHI turbo I never came across any threads on IHI rebuilds so I figured I’d post up my rebuild experience/steps I took. With all DIY threads theres other ways of performing the work, this worked best for me. I’d also like to add that I’m turbo dumb so the wording I use maybe incorrect but I’ll try my best in getting it right.
This is the turbo I used in my experimenting with porting and polishing, not pretty but nothing some cleaning won’t fix or a grinder, haha. Picture #1
First thing I did was remove the compressor housing, removing the 6 – bolts on the back side followed by rotating it clockwise to break the RTV seal free, 12mm socket. I also removed the E-clip from the waste gate shaft to remove the waste gate assembly. Picture #2
Here’s a back shot of the cover so you can see the 6 bolts I’m talking about. Picture #3
Now with the cover removed you can take off the compressor wheel using a 13mm socket. Remember the shaft threads are reversed so a clockwise rotation removes the nut and counter-clockwise screws the nut back on. To keep the shaft from spinning you'll need a 12 point 14mm socket on the exhaust side of the shaft. I resorted to using channel locks to remove my compressor wheel due to it being stuck, which destroyed the wheel. Picture #4 & #5
Once you’ve removed the compressor wheel it’s time to unbolt the back side of the compressor cover using a T-20 torx bit (not 100% sure at the moment). On this turbo they came off fairly easy but the other one I did were tight; be sure to push in tight on the socket so the torx bit doesn't fall out of the bolt head when removing. Picture #6
As you can see the cover can only be positioned/bolted on one way. Make sure you clean the very center being thats where the oil drains back into the engine. Now with that removed it’s time to unbolt/remove the band clamp using a 10mm socket. Picture #7
With the band clamp removed separate the center section from the exhaust housing. This isn't the easiest depending on how stubborn your turbo is. You can take a hammer and hit the drain flange to break the center section free from the exhaust housing but don't hit to hard or you’ll mushroom the flange. You also don’t want to hit very hard or you’ll bend or break the small dowel pin that positions the center section and exhaust flange. Picture #8
When separating the center section from the exhaust housing be very careful to not have the exhaust wheel come in contact with the exhaust housing so you don’t wreck the wheel; I found spinning the shaft each time you move a good way to insure theres no wheel contact. Also be aware of the copper shims between the center section and exhaust housing; they’re delicate so remove them and place off to the side. Picture #9
This is the turbo I used in my experimenting with porting and polishing, not pretty but nothing some cleaning won’t fix or a grinder, haha. Picture #1
First thing I did was remove the compressor housing, removing the 6 – bolts on the back side followed by rotating it clockwise to break the RTV seal free, 12mm socket. I also removed the E-clip from the waste gate shaft to remove the waste gate assembly. Picture #2
Here’s a back shot of the cover so you can see the 6 bolts I’m talking about. Picture #3
Now with the cover removed you can take off the compressor wheel using a 13mm socket. Remember the shaft threads are reversed so a clockwise rotation removes the nut and counter-clockwise screws the nut back on. To keep the shaft from spinning you'll need a 12 point 14mm socket on the exhaust side of the shaft. I resorted to using channel locks to remove my compressor wheel due to it being stuck, which destroyed the wheel. Picture #4 & #5
Once you’ve removed the compressor wheel it’s time to unbolt the back side of the compressor cover using a T-20 torx bit (not 100% sure at the moment). On this turbo they came off fairly easy but the other one I did were tight; be sure to push in tight on the socket so the torx bit doesn't fall out of the bolt head when removing. Picture #6
As you can see the cover can only be positioned/bolted on one way. Make sure you clean the very center being thats where the oil drains back into the engine. Now with that removed it’s time to unbolt/remove the band clamp using a 10mm socket. Picture #7
With the band clamp removed separate the center section from the exhaust housing. This isn't the easiest depending on how stubborn your turbo is. You can take a hammer and hit the drain flange to break the center section free from the exhaust housing but don't hit to hard or you’ll mushroom the flange. You also don’t want to hit very hard or you’ll bend or break the small dowel pin that positions the center section and exhaust flange. Picture #8
When separating the center section from the exhaust housing be very careful to not have the exhaust wheel come in contact with the exhaust housing so you don’t wreck the wheel; I found spinning the shaft each time you move a good way to insure theres no wheel contact. Also be aware of the copper shims between the center section and exhaust housing; they’re delicate so remove them and place off to the side. Picture #9