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Turbo Rebuild
My upgraded stock turbo started blowing oil on the exhaust side. I could smell the hot, burning oil and there was noticeable oil smoke at idle. Instead of dealing with a few weeks of downtime, shipping charges, etc. I called up Turbonetics and got a basic rebuild kit. IMHO, if you need a rebuild kit, I would recommend Turbo City. They cater to do-it-yourselfers and have a really nice kit with a video and stuff for about the same price I paid for a basic kit from Turbonetics. You'll need - - normal tools to remove the turbo - a set of VERY small snap ring pliers. I found some at Napa that worked after searching all over creation. Look for snap ring pliers that have 3 sets of tips that you can swap in. The black set is the right size. - a homemade turbo stand. This makes life a LOT easier. I'll get to that... - a 13mm 12-point socket - 13mm combination wrench - 10mm combination wrench - PB Blaster (penetrating lubricant) - a hammer - a rubber mallet - a paint-size can of carb cleaner - compressed air - either from a compressor, or in a can. - a brass brush - a little Hylomar OK, so you've got the turbo off the car. Time to make a turbo stand. I have an engine stand that's made of 2 sawhorses and a thick piece of plywood with appropriate holes drilled in it. Set the turbo exhaust studs down (so it's standing on them) onto the plywood. Make the turbo straight so the exit from the intake housing is pointing away from you - you get the idea. Draw circles around where the exhaust studs are touching and drill stud-sized holes there. The turbo should now fit down into the board snugly. Now, it's time to strip down the turbo. First, some background on the nomenclature - - the bright aluminum side of the turbo that the inlet duct and intercooler piping attaches to is the compressor housing, and the compressor wheel is inside it (that's what spins to compress the air) - the cast iron "hot" side of the turbo that the exhaust bolts to is the turbine housing, and the turbine is the wheel inside. - The center section is the middle part that the oil and water lines attach to. - The backplate is the back section of the compressor housing - it's aluminum. It's bolted to the center section, and the compressor housing is attached to it. - The wastegate actuator is the metal thing with a vacuum hose under the compressor inlet that has a rod going to the turbine housing. OK, now that it's on your stand, time to remove the oil and water lines. Both oil lines attach with 12mm bolts, top and bottom. The water lines attach with 21mm banjo bolts. They're on there pretty good - might require some creativity, especially if you don't have air tools (impact gun good :). With that done, look at the end of the wastegate actuator rod. There's a C-shaped clip that holds it on. You should be able to remove it with a screwdriver and a pair of needle nose pliers. Put the clip in a safe place. The rod should pull right off - it can move around some. Go ahead and remove the actuator itself. It's attached to the compressor housing with 2 13mm bolts. If you can't get enough torque on them. put the 13mm combination wrench on and tap it with a hammer. This is the only way you're gonna get most of the bolts off is with this technique. You might want to just cut the vacuum line running to it and replace it later. With that off, it's time to remove the turbine housing. There's 6 13mm bolts holding it on with small brackets sandwiched between the bolts and the housing. This is a compression fitting - you'll understand once you get it apart. Take off the 4 bolts that you can easily get to - again, with a combination wrench and a hammer. There's 2 bolts directly under where the oil lines attach. Before you loosen those, mark the relationship of the turbine housing to the center section. Use a marker, or some white-out, or a grease pencil just to check yourself come assembly time. Start in on those two bolts. They'll eventually start hitting the center section - that's OK. Work on each side, alternating back and forth. The bolts will push the turbine housing off. Eventually it will be free and you can remove the bolts. Lift the center section straight up - it should pull free easily. You'll see the whole turbine wheel now. For the next part, I like using the top of a cardboard box on the floor. The compressor housing is aluminum, and can scratch or ding easily - the cardboard will cushion it a bit. Set it so the inlet side is down, and it's standing up on it with the turbine wheel straight up in the air. Start working on the 13mm bolts that hold the compressor housing on. 2 of the bolts hold on the little bracket that the wastegate vacuum line is on - you can cut the line if necessary. Once you get all the bolts off, the center section should lift right off. If not, use the rubber mallet on the compressor housing to tap the housing off. Now, you should see the whole compressor wheel. This is where it starts getting fun. Right now, you're down to the CHRA - center rotating housing and assembly. You can buy preassembled CHRA's and just bolt your housings on if you don't want to go further. It's not that hard, so I think it's worth it to go further :). Next step is to remove the compressor and turbine wheels. Mind the compressor backplate - it's soft aluminum, and you don't want any dings on it or it might not seal up properly. You need to mark the wheels at this step. Put a scratch or a Sharpie mark on each wheel and the compressor nut so you can return them to their original positions. Put the 13mm 12 point socket on your socket wrench and put that on the nut that's sticking out of the turbine - it should fit right on there. Put the 10mm combination wrench on the compressor wheel's nut. Hit the wrench with a hammer to break it loose and spin the nut off - it will fight you all the way off, that's normal. Now, hit the threaded shaft sticking out of the compressor wheel (what you just took the nut off of) with the rubber mallet - keep tapping on it until the shaft and turbine wheel come all the way out. The shaft and turbine wheel are all one piece. Set that to the side, and place the compressor wheel off to the side. There's also a loose heat shield right behind the turbine wheel - set that to the side too. Behind the compressor wheel is a small aluminum spacer that went around the shaft - remove that and put it with the compressor wheel. Now it's time to take the backplate off. It's held on with 4 10mm nuts. Remove them and remove the backplate - it might need a tap or two with the mallet to come off. With that out, we've got some new parts to identify. There's the thrust bearing and collar - the thrust bearing is a brass bearing that kinda looks like Pac-Man. The collar is in the middle of it. These should lift right out - it sits on pins on the center section. Note which side faces up, and which faces down. Around the thrust bearing in a groove is a rubber O-ring. Pick that out with a dental pick or a small screwdriver. OK, now we've taken the turbo pretty much all the way apart. Time to remove the shaft bearings. If you look in the hole the shaft fits into on both sides, you'll see a brass bearing held in with a snap ring. Get the snap ring pliers, attach to the snap ring, compress it, and lift it out. It may take a few tries - if the pliers fit well, it's pretty easy. The bearing should slide right out - if not, turn the center section over and tap it so it falls out in your hand. There's another snap ring on the other side of the bearing - it's not necessary to remove this. Now it's time to remove the turbine seal. If you look at the turbine shaft, right behind the wheel, there's a piston ring type thing. It should be loose and spinning around - it's a metal ring that has a small gap in it. Use the snap ring pliers to expand the ring and remove it. This will take a few tries. Time for cleaning! Open the paint can of carb cleaner and put the center section, turbine shaft and wheel, and compressor wheel in there. The outer housings you can clean with Super Clean or something and scrub with the brass brush. Let the parts soak for a few hours in the carb cleaner. Remove 'em and clean 'em with the brass brush if necessary. You want to make sure the turbine shaft is as clean and smooth as you can get it. If you have a bench grinder and can put a brass wheel on it, that would work great. It has to be soft - you don't want to ding up the shaft! After everything's nice and clean, blow it all out with compressed air. It needs to be CLEAN on all the bearing surfaces - you don't want a bit of sand or something in there! Time to put it back together. Start with the turbine seal - the piston ring thing. Coat the shaft with assembly lube, and put some on the ring too. Using the snap ring pliers, put it in it's groove by expanding it slightly and snapping it into place. It will be loose when it's on there - that's OK. Don't overexpand the ring or deform it - it's a precision fit. Time to put the shaft bearings in. Coat them in assembly lube, insert them in their respective spot, then put the snap ring in to hold it in place. Next is the rubber o-ring seal on the compressor side of the center section. Put a light coat of Hylomar on it and put it in the groove. Install the thrust bearing and collar next, again with plenty of assembly lube. There's another seal in the compressor backplate - it's the compressor seal, and it's right around the hole that the shaft goes through. You should be able to drive it out from the wheel side of the backplate. Press the new seal in - be careful with it, the rubber on the seal can crack or tear. Again, use assembly lube on it. Bolt the backplate to the compressor housing. Time to install the shaft. With the compressor side pointing down, put the heat shield on the turbine side. Bring the shaft down into the hole - go smoothly, or you could nick the shaft bearing surface. The shaft will stop when it gets to the turbine seal. Where the turbine seal goes into is tapered. This is the tricky part of the job. Press firmly down on the turbine wheel, and slowly rotate it around. You're trying to get the ring to align on the tapered part of the center section so it compresses the ring around the shaft. It will eventually slide in and "click" into place. Take your time with this, don't try and tap it in with a hammer, just be patient. With that done, install the spacer and the compressor wheel on the other side. Put the nut on the shaft - don't use any loctite, it's a self-locking nut. Make sure the turbine and compressor wheels are lined up with each other, then tighten the nut down. It should snug down against the shaft - you want it secure, but don't he-man it. The torque is spec'd in the inch-pounds. Once it's on, the center section should spin freely if you hold the heat shield in place. Time to put on the compressor housing. I usually put a little Hylomar where the backplate meets the compressor housing - just a LITTLE, mind you. Line it up appropriately - if you can't remember what position it goes in, it's easy. The oil fitting with the small hole in the middle is the inlet, on the top of the turbo. Line the oil entry hole up with the top middle bolt hole on the compressor housing. Put all the bolts in, remembering to reinstall any brackets. Tighten them down, then tap-tighten them with the hammer and combination wrench. The torque is 40-50 foot-pounds, ballpark. Again, make sure the turbo spins freely. OK, now for the turbine housing. Put it on your turbo stand, and set the rest of the turbo onto it. You'll have to start the top and bottom bolts that hit the center section first. Don't forget the bracket that goes around the bolts - evenly tighten all the bolts so the center section compresses itself into the turbine housing. Keep checking and make sure the turbo still spins freely and that it's not hanging up. Finally, bolt the water/oil lines and wastegate actuator on. There's really no breakin for a turbo. It's a good idea to pull your fuel injection fuse and crank the car until you see oil pressure on the gauge - that will get oil flowing to the turbo's bearings before you start it. Reinstall the fuse, start it up, and let it sit and run at idle for a while - check for leaks and make sure it's all on there good. Go out and terrorize some Hondas :). Couple of notes - 1. Make SURE the hose going to the wastegate actuator is secure. If there's a leak in it, you can have overboosting problems big time. I would replace the hose with brand-new hose if possible, preferably silicon, and use metal spring clamps to hold it on. If you have an '89-91 turbo, there's a small "pill" in one of the hoses - it's a little metal pill with a hole in it. Make sure to transfer the pill to the new hose. 2. If the compressor wheel or turbine wheel is bent, broken, mangled, etc. when you disassemble it, throw it in the trash. Buy a used or a new replacement. You'll have major problems if you use damaged wheels! The most common signs of turbo failure is oil smoke or the "whine of death". Oil smoke is bad bearings and a bad turbine seal, and the whine of death is when there's enough play in the bearings that the wheel starts to hit the housing. This literally sounds like the siren on a cop car. It's usually the compressor wheel that hits - that's then a junk wheel and housing. Turbo rebuilding is a lot less precise on your part than you'd think. All the precision work is done by the factory - you just plug in new precision parts. The biggest thing to remember is to take your time and be meticulous - label things if necessary, keep parts organized, watch how they come off so you can reinstall them. I rebuilt my turbo on a Saturday - that's pulling the turbo, rebuilding it, and reinstalling it and on the road by 5pm. It's not hard at all. I've had great luck with my rebuild - no more oil smoke, no wierdness, just boost :).