I don't know if anyone remembers that far back but newby1gsx was having trouble with his Evo III after he ported the turbine housing. he ended up selling the car and I bought the turbo from him to rebuild it. And now, because i'm bored, you all have to suffer through me posting pics througout the entire process(thanks again Eric!) (IMG:style_emoticons/default/grin.gif)

This process assumes the turbo needs rebuilt. In this case the turbo was known to not have been primed properly (easy mistake), made a squealing noise under boost, had slight side to side play and slight in and out play.

I won't be showing you how to evaluate whether or not you should rebuild it but if you think it might be time,,,,,,do it. also, I only have 2 hands and the camera took up one of them so don't ask, "you say to use two hands but I only see one?" or, "why is that tool just laying in there?")

Step 1:
taking it apart. Since the turbine housing was already off when it arrived I won't be showing you that part until later. basically I just forgot to take a pic (IMG:style_emoticons/default/blush-anim-cl.gif)

Step 2:
you need a large set of snap ring pliers for this. remove the snap ring by squeezing the ring with the pliers and lift up lightly on the back side like so...


Step 3:
gently (with both hands) seperate the compressor housing from the center cartridge. be careful because if it "pops" off you may bend one of the fins on the compressor wheel

it will look like this when you get them apart


Step 4: (I only used marker for this step because i'm sending it away to be balanced)
Mark the EXACT location of the compressor wheel, nut, and turbine shaft. usually you would use a small punch and soft hammer to scribe/punch location marks but like I said, I just used marker for an example. Put marks in 3 unevenly spaced locations. Making unevenly spaced marks will ensure that you line everything up the right way. if they are evenly spaced you don't know if the marks are back in their original location.





more to follow tomorrow, i'm goin golfin bitches!!!!!!!!!!!!!! (IMG:style_emoticons/default/laughing.gif)

golf sucked, we ended up going to a par 3 (IMG:http://smiliesftw.com/x/4.gif)

but I digress, back to the subject

Step 5:
now you have the center cartridge entirely seperated from the outer housings. attach a 12mm box end wrench to the turbine wheel and a 10mm box end wrench to the compressor wheel nut(I used a ratchet here but I should have used a shorter socket or wrench instead, do what I say not what I do :blush-anim-cl: ). secure the housing and brace the wrench on the turbine wheel against something so it doesn't spin, I used the floor. GENTLY and i mean GENTLY!!! loosen the compressor nut CLOCKWISE. yes, CLOCKWISE, it is reverse threaded. You will here a little ping when the nut breaks free. if you yank on it too hard you risk breaking the threaded end off the turbine wheel. this is a $180-200 mistake.


Step 6:
spin the compressor nut completely off and slide the compressor wheel off


EDIT: I forgot to add that once you have the compressor wheel off you can pop the turbine wheel out (see steps below). I've always left it in when taking them apart just out of habit so that's why I did it that way.

Step 7:
take your snap ring pliers and remove the front seal snap ring

it is tapered so that it applys pressure to the seal. the flat end goes down when you reinstall


Step 8:
use a small screw driver and pry the seal out. again, be very gentle!

once it pops loose slide the whole assembly off of the turbine wheel. the collar and thrust bearing spring will seperate easily from the seal plate. the collar is held to the spring by a small circlip. this circlip needs to be replaced

Step 9:
look inside and you will see the thrust bearing

slide a pick gently behind the thrust bearing and even more gently work the bearing side to side until it comes free and you can slide it off the shaft

9 times out of 10 the thrust bearing collar will stick to the bearing as you slide it out but if it doesnt slide it out by itself

inspect the thrust bearing for damage/wear
Front

Back

in this case the bearing and collar look like they only has 2000 miles on them. This is obviously not the cause of the noise created by the turbo

Step 10:
tilt the cartridge forward and slowly spin the turbine shaft. the journal bearing will work its way out and you can then slide it off the shaft


I didn't include a pic but this bearing looked to be in great shape as well. slight wear that may have been caused by the turbo not being primed correctly but nothing to be concerned about one bit

Step 11:
secore the cartridge then gently push with even and increasing force on the turbine shaft to pop it out the back of the cartridge. It will suprise you when it pops loose the first time you do this. don't worry :grin:

Step 12:
the rear journal bearing should pop out and remain on the shaft but if it doesn't use your pick to gently pull it out. inspect the bearing

this is where I start to notice problems. The bearing has deep wear marks and the oil holes are clogged with a mixture of sludge and coke (the probable cause of the wear marks)

Step 13:
inspect the turbine wheel and shaft for wear from the journal bearings, thrust bearing collar, and the rear seal

This is also covered with sludge and coke. The circlip began to weaken and was starting to lose its sealing ability.


so now i'm at the waiting portion. once the rebuild kit arrives I will send the wheels out to be balanced and drop the center catridge at the machinist to be cooked/cleaned. during all this time I will post more pics of how to measure the turbine wheel and how to remove the rubber seals on the cartridge before taking it to the machinist. i will also post pics of the port job. He was having boost creep issues and tried porting to help the wastegate do it's job. i don't know if this was his first port job or not but I was very impressed, not that i'm a porting genius or anything, but he created the proper shape in the housing, pulled back the wastegate outlet at the proper spot and the proper distance, and smoothed everything nicely. The only thing I might do is smooth out the inlet portion just a little bit but he did a fantastic job

but for now, i'm at work :grin:

Why Thanks Greg.. I impressed myself to!.. lol!

almost seems like the issue is just a coincidence that happened when i put it back on.. I did know that the turbo was buring oil before i pulled it. Anyways, I searched for a thread like this before I sold the turbo.. Glad my misfortune could bring everyone to a higher level of understanding on this.. ;)

I'm starting to think that when you pulled the turbine housing to port it some of the coking flaked off and got underneath the heat shield. Then when you put the housing back on that coking wouldnt let the shield go back to where it was supposed to be pushing the heat shield out just far enough. When the turbo would spool the wheel pulled forward just enough to rub that heat shield giving you the noise you heard.

Just curious, I never asked, how many miles are on it?

I would gestimate about 15-18,000 is all. Tops 25,000.

cool. it definately seems low mileage. the seal and rear bearing were probably being slowly murdered by the heat caused when it kept boost creeping

or from the 15000+ miles of runnin wide open due to a rigged set up?!
Remember i replaced tubing to find that the only reason it was holding at 14lbs was due to all the clamps being loosened enough to let it leak just right!!

That must have taken for ever to get it right! Why he didn't just pull it and port it is beyond me...

that could be possible also :grin:

Here are some pics of Eric's port job( :clap: ):




You can see here how he pulled the top of the wastegate port back. In an unported housing the are almost even with each other and pulling the top part back will help the wastegate do it's job and decrease boost creep



This is the best possible port shape. Garrett does it VERY well in their turbine housings. Mitsu doesn't, so when you port it is beneficial to try and mimic the shape as best as possible without taking too much material out.


These are enhance pics to show how close Eric got it, it's very difficult to do. I wish I had an unported pic to show you how much he reshaped it for the better. :



This is an enhanced pic of where I will try and remove just a little bit more material. Everything else is perfect as far as I can tell (again i'm not a porting genius) but I can open up the inlet just a little bit larger.


p.s. I drew all the shapes in paint so they aren't the smoothest but you can get the idea