How to rebuild a stock 86-87 turbo

[joey316g]

Ok guys, I posted in the turbo section to see if there would be any interest in this how to and some people said they would like to see it so here goes. I hope everyone finds this useful. Its gonna be full of pictures and will be very detailed. I looked around but did not see an in depth how to anywhere so I figured I would do one up...

Kits can be obtained from many turbo parts suppliers. ******* is a great source for parts and there are a few good places on *****...not all but a couple of good ones. I will say that I got no help from one of our "supporting vendors" when it came to parts but I will leave that alone. To each his own.

Hopefully this will make it easy for most do it yourselfers. In all honesty, this is not very hard and doesnt require many special tools. The tools needed are as followed but not limited to:

10mm, 13mm and 5/8 combination wrenches
center punch
hammer
dead blow hammer
snap ring pliers
needle nose pliers
11mm 12 point socket
Torque wrench capable of 18-20 INCH lbs.

For some parts, sockets can be substitued for the combo wrenches but the wrenches are a must.

DISASSEMBLY:

Ok this is what you should have. Mine was using oil at a fast rate. Thats why it is getting the rebuild.

Step 1. Remove snap ring from waste gate swing valve arm.

Step 2. Remove waste gate actuator bolts and remove actuator.

Step 3. Make an index mark on compressor housing and back plate. This will make lining it up on assembly a snap.

Step 4. Remove the rest of the compressor bolts and clamps.

Step 5. Remove compressor housing carefully not to damage compressor wheel.

Step 6. Hold on to the compressor clamps even if your kit cam with new. The new may not fit. Mine didnt.

Step 7. Remove exhaust elbow bolts.

Step 8. Remove exhaust elbow.

Step 9. Remove turbine housing bolts except the ones under the oil inlet and outlet of the center section.

 

[joey316g]

Step 10. Make index marks again in center section and exhaust housing to ease reassembly alignment.

Step 11. Now start backing out the 2 bolts left on the turbine housing. Use them as jack bots to aid in seperating the exhaust housing. Use penetrating oil here too. May also require a few shots from a dead blow hammer. Be patient. They will come apart.

Step 12. At last! Remove turbine housing again being careful to not damage wheel.

A SMALL SIDE NOTE: these bolts are old and rusty. Hopefully you will get lucky and they will all come out. I had to chisel this sucker off and get it out later.

Step 13. Make index marks on compressor wheel and end of turbine shaft again to aid in assembly realignment.

Step 14. Remove nut on end of shaft. This nut comes off in the standard rotation.

Step 15. Remove compressor wheel and thrust spacer from shaft.

Step 16. MAke index marks on compressor back plate and center section. This is more for keeping the mark made earlier for compressor lineup in the same position.

Step 17. Remove 4 bolts holding back plate to center section.

Step 18. Remove backplate. Dont worry if the thrust bearing or carbon seal falls out. Ill cover the way they go back on during assembly.

 

[joey316g]

Step 19. Remove thrust bearing and collar.

Step 20. Remove turbine wheel/shaft. Just pull it straight out.

Step 21. Remove exhaust shield.

Step 22. Remove compressor side bearing snap ring.

Step 23. Remove compressor side bearing.

Step 24. Remove turbine side snap ring.

Step 25. Remove turbine side bearing. A SIDE NOTE. there is no need to remove the inner snap rings. They are hard to get to and can remain in.

Step 26. Remove old square cut o-ring on compressor side of center section.

 

[joey316g]

Step 27. Take the back plate and remove the thrust star spring.

Step 28. Remove the carbon seal, washer and spring

Step 29. Remove the piston ring exhaust gas seal from the turbine shaft. The snap ring pliers can be used here for this.

OK that concludes the disassembly process. WHat you are going to need to do now is give everything a good cleaning. Start by degreasing everything by using some type of solvent. If you have access to a media blaster, you can do the exhasut housing, elbow, compressor housing, backplate, and turbine wheel. NOTE: mask off the shaft if you are going to blast the wheel. You dont want to blast the shaft. It can be lightly polished with 600 grit sandpaper and some oil. Also, make sure you clean the piston ring groove in the shaft very well. A wire brush helps here. I chose to not blast the center section. I did not want to introduce any media into the area the bearings were going to get oil. Instead I soaked it and the compressor wheel in carb cleaning fluid overnite and blew off with compressed air. You can also use a wire wheel on these items if a media blaster isnt available. Once everything is cleaned, inspect all parts for damage. If any parts are damaged, replace them especially exhaust and compressor wheels. If a NEW turbine wheel or compressor wheel is needed, you must have the turbo assembly rebalanced. Im not going to go too far in depth in with the inspection process. If you are attempting this, you should be able to tell when something is messed up or not. :biggrin:

This is my parts layed out, cleaned, inspected and replaced as needed.

Heres my new parts layed out.

A small note about the bearings and seals. Its good to tear down the turbo before you order your kit. This turbo is stock. Yours may appear to be but when you open it up, you may find something other than what you see here. Thats ok, all that means is someone was in there before. Once you tear it down and inspect everything, you can order the correct parts for your turbo. The bearings may have a number on them. This number often denotes a bearing size. when ordering your kit, let your parts supplier know so they can give you the same bearing that came out. Also, with the seal on the compressor, the stock cmae with a 4 piece carbon seal but sometimes these turbos are modified for a different type so note that as well. Last, you may see a thrust bearing that is bolted down and full round. This is a 360 thrust bearing. It is another modification. This is why im telling you to tear down and inspect first so you can get the parts you need be it consumables or hard parts all at the same time.

For assembly I will simply be using some STP Oil Treatment. Its nice and sticky and stays put until you put your part in service.

 

[joey316g]

ASSEMBLY:

Step 1. Install new bearing in the compressor side bore. Oil it up first.

Step 2. Install snap ring on compressor side bearing.

Step 3. Install new bearing in the turbine side bore. Oil it up.

Step 4. Install snap ring on the turbine side bearing. This one is tricky. Make sure its in the groove and seated properly by tuggin on it with a pick.

Step 5. Install piston ring on turbine wheel shaft.

Heres what it will look like installed.

 

[joey316g]

Step 6. Lube up thrust bearing and collar. Install collar into thrust bearing and place on dowel pins on compressor side of center section

Take a look at this bearing and collar. When installed correctly, the tapered side of the collar and the grooved side of the bearing will go toward the shaft bearing. The tapered side of the collar goes directly over shaft bearing inside the bore.

These are the components that make up the shaft seal on the compressor side. A carbon seal, o-ring, washer and spring along with thrust star spring and backing plate.

Step 7. Install the o ring into the back of the carbon seal and lube it up.

Step 8. Install spring in compressor back plate. Its conical. Place the small end in first.

Step 9. Line up the notches in the washer to the tabs in the back plate and push it down.

Step 10. Line up the notches in teh carbon seal, and push it into place making sure the oreing slide over the center of the back plate. Again lube it.

Step 11. Install the thrust star spring into the back plate. Make sure it snaps into place.

Step 12. Install the square oring into the groove on the compressor side of the center section. Use a little grease to hold it in place.

 

[joey316g]

Step 13. Now carefully place the compressor backing plate with the carbon seal installed on the center section aligning the index marks made during disassembly. Be careful here that the seal doesnt pop out and the thrust bearing doesnt move.

Step 14. Install 4 bolts and tighten down in a criss cross manner.

HERES WHAT YOU SHOULD HAVE SO FAR. ALmost done.

Step 15. Install exhasut shield

Step 16. Take turbine shaft and lube up pistin ring and shaft. Now carefully place intop center section and wiggle it around while turning to seta it all the way in. When installed correctly, the blades should almost touch the exhasut shield.

Step 17. Install thrust spacer on shaft.

Step 18. Install compressor wheel.

Step 19. Align index marks made during disassembly and install nut. Tighten nut to 18-20 INCH LBS and the give it a 90 degree turn. Just a little oil on the threads here. NOTE: If you had your assembly rebalanced, no need to realign the index marks

 

[joey316g]

STep 20. Carefully install turbine housing. Put a little oil around the lip and alighn the index marks made during disassembly. This part is kinda tricky. Remember the two bolts that were adjacent to the oil inlet and outlet. They have to be installed as the hosuing is being installed along with the housing clamps. Be patient.

Step 21. Installl all the compressor bolts with a little oil and tightem evenly in a criss cross pattern

Step 22. Install o-ring around the inside of the compressor back plate.

Step 23. Install compressor housing aligning the index marks made during disassembly

STep 24. Install compressor clamps and bolts and tighten up. Make sure to leave the ones for the actuator available.

Step 25. Install exhaust elbow.

Step 26. Install actuator and adjust arm so that it needs to be pulled out an 1/8 of an inch to slide ofer the waste gate swing valve arm pin.

Step 27. Install E Clip on waste gate swing valve pin.

 

[joey316g]

Step 28. Install new gasket on compressor inlet for bell and bolt on inlet bell.

And there you have it. Your freshly rebuilt turbo ready to be put in service.

I hope this helps someone in the future. If there is any way I can be of any assistance or there are any questions, please feel free to ask away. No question is a dumb question. The only ones that are dumb are the ones that arent asked.

Id like to give a special thanks to usetaboost for hookin me up with a replacement turbine wheel. He is a good guy to deal with.

 

[usetaboost]

THIS is the kind of write up needed for doing our turbos. Good job bro! Nicely detailed and good descriptions. The instructions given with the kits are crap compared to this.

 

[joey316g]

Thanks brotha....just trying to give a little back to the community...by the way...i laid down a set of tracks today about 100 feet long and let out of it....Ill be doin an engine rebuild how to soon....LOL

 

[charlief1]

You did a good job on the write up, and I will point out that this is the same way all for the stock Buick V6 turbos are done. This isn't exclusive for the 86-87 except for the carbon seal in some cases.

 

[usetaboost]

Thanks brotha....just trying to give a little back to the community...by the way...i laid down a set of tracks today about 100 feet long and let out of it....Ill be doin an engine rebuild how to soon....LOL

Yeah the stock turbo is pretty fun once you get the exhaust side of the car opened up and put on a mbc. Can't beat 'em just for cruisin the streets.

 

[joey316g]

You did a good job on the write up, and I will point out that this is the same way all for the stock Buick V6 turbos are done. This isn't exclusive for the 86-87 except for the carbon seal in some cases.

Thanks Charlie...the reason i put 86-87 was because I didnt want to mislead anyone with the pictures. But true, this procedure can be applied to the other turbo buick turbos as well as many T3/T4s for the most part.

 

[ttaowner]

i would suggest using heat(torch) to heat up the cast iron housing in order to attempt taking off the exhaust elbow or probably trying to unbolt the center section from the exhaust housing and definately dont reuse those bolts as they are fatigued from the hot cold cycles.


great article very detailed

 

[joey316g]

i would suggest using heat(torch) to heat up the cast iron housing in order to attempt taking off the exhaust elbow or probably trying to unbolt the center section from the exhaust housing and definately dont reuse those bolts as they are fatigued from the hot cold cycles.


great article very detailed

Thank you.....Yes heat can definitely be used...another good tip..... the full rebuild kits I have used all came with new bolts for both compressor and turbine housings...not for the elbow though but you can easily pick up some 8m x 1.25 x 20mm grade 10.9 bolts at the hardware store for that.

 

[ttaowner]

how much time would you estimate to disassemble / clean / rebuild

how much is a rebuild kit for stock turbo that doesnt need any wheels ?

thanks

 

[Infamous'86GN]

Interested in the above post also^

And Thank you awesome thread! this will be my next project.

 

[joey316g]

how much time would you estimate to disassemble / clean / rebuild

how much is a rebuild kit for stock turbo that doesnt need any wheels ?

thanks

Well if everything comes apart easily, were talking like 2 hours for disassembly, maybe an hour for cleaning and inspection and maybe 2 hours to assembley so 5 hours labor if everything goes smooth.

Kits range in price. There are basic kits that only contain bearings and seals. They are around $50-$60. The full kits come with hardware and some extra parts. I strongly recommend the full rebuild kits for the thrust collar and star spring alone. They can range from $80 to $100 depending where you purchase from. Also pick up a graphite 3 bolt flange gasket. The factory didnt install gaskets here when new but you can bank on the flange being warped a little...enough to leak. This is right next to the O2 sensor and causes high idle BLMs that make people crazy trying to find. SCE makes a nice gasket.

 

[usetaboost]

gpopshop I remember they are around 100 shipped. the 360 thrust is extra. Joe is right about keeping the clamps. I had to reuse a few of mine also. I used the ones from the kit to rig up my stock wastegate to the turbo. Not pretty but it's on straight and it works. Just make sure you order the right kit. If in doubt sent them an email. The good thing about these guys is that they also sell used stuff if available and also sell new. They will take the time to explain things and answer questions not only by email but also over the phone.