2.) Remove all oil fittings and Scribe the Compressor housing and backing plate so you can re-align easily when you re-assemble

3.) Remove 6 compressor housing retaining bolts.

4.) After the bolts are loose you will have to remove the compressor housing. I had to tap mine lightly with a hammer to loosen it.

5.) The compressor wheel will now be exposed. You will need a 12 point socket on the compressor side and a six point on the turbine side to remove the nut holding the wheel on. After you remove the nut, the compressor wheel should just slide off of the shaft. I would use a magic marker to index it on the shaft for reassembly. Be very careful with it, you don’t want to bend any of the blades.

6.) Remove 4 Compressor housing backing plate bolts and slide off backing plate. Note rubber gasket on back and seal assembly.

7.) Put the backing plate on a rag face down. You should be looking at the thrust bearing and seal assembly. If you push the center of the assembly from wheel side to back side it should all come out. Pay attention to the order of the parts behind the thrust bearing. There are several different types of seals so each one is different but you should just be able to remove and replace the seal. Pop out the “Star Wheel” behind the TB it will probably be bowed when you remove it. It should be flat when you reinstall it. I used a 36mm socket to push it in evenly. After you have R&R the assembly (be sure to give everything a coat of oil when you reassemble) set the cover aside.

8.) Remove the Center section from the exhaust housing. Remove all the turbine housing bolts except for the two at the top and bottom of the housing (next to the oil in and out) Use these two bolts to “Jack up” the Center section ¼ turn at a time. The turbine housing needs to come off the center section parallel to the turbine wheel. If allowed to come off at an angle it will bind on the turbine wheel and damage it. After EACH ¼ Turn spin the shaft to make sure it is not binding. IF you feel to much binding tighten bolts and restart. Use a lot of penetrating oil also.

9.) After the exhaust housing is off a light tap from the compressor wheel side of the shaft should remove it from the center section. Slide off the “Dog Bowl” shaped cover. My seals leaked pretty badly so there was a lot of build up here. I used a brass brush, a dental pick, and carb cleaner to remove all of the gunk. You should also find a snap ring around the base of the shaft next to the exhaust wheel replace it with the new one from the kit. Set the wheel and shaft aside

10.) REPLACING THE JOURNAL BEARINGS. There is a Journal bearing on both sides of the center section. To remove them you will need a set of snap ring pliers with really small ends. I bought a set at harbor freight and ground done the points to fit in the snap rings. Remove the snap rings and the bearings should slide out. Give the new ones a good coat of oil or assembly lube if you want to be a professional. Put the new ones back in and replace the snap rings making sure that they are seated properly.

11.) Reassembly. Replace everything in the opposite order of break down. Use oil or assembly lube on all moving parts and make sure you replace all the gaskets on the compressor side. Line up all of you index marks when putting it back together and it should still be in prefect balance. Leave the compressor housing bolts loose until it is back on the car just in case your alignment it off. Compressor nut torque is 18-20 in-lb (NOT ft-l b) I did mine hand tight plus a ¼ turn since I don’t have a torque wrench that small. Prime the oil system with the coil unplugged to get oil to the turbo before you crank it up.

I did mine last week and the smoke has gone down a ton. I still smoke a little but I think that is because of my rings and 200,000 plus miles on the motor. This is the first time I have done this so if I did something wrong I can’t take any liability. Mine works though, lag time went down as well as the smoke. Over all it took about 3 hours but I stopped and cleaned everything up real nice. Good luck guys I hope this helps somebody out there!

Josh

P.S. TOOLS you will need
13mm wrench
7/16 12 point socket
5/8 six point socket
carb cleaner
brass brush
assembly lube
inside snap ring pliers with "itty-bitty ends"
A vise makes a handy place to hold the turbo but it is not nec.

Note added by WDRacing Some shafts have a reverse thread on the compressor side and should be noted upon compressor wheel removal. WD

Modified by LEMHEAD16 at 11:23 PM 6/13/2006

1 question dont you need to balance the turbo again? after re installing everything?

Its almost absurd to pay more than 150 for a turbo rebuild including the kit. That is NOT including balancing, damaged compressor or backplate or damaged CHRA.

You should also put up a list of the tools you've used. I found that rebuilding my SR T25 was a PITA when I did not have the correct tools available!

Good write up and reference!

Thanks for the tool reference.

Modified by wannawangan at 8:09 PM 6/14/2006

http://cgi.ebay.com/ebaymotors...&rd=1

thought I would note a few things

0.030 (approx 1/32nd )snap ring ends should do the trick for most turbo rebuilds.

snap rings can have a tapered edge and need to be seated 1 way (facing outward).

soaking everything in oil for awhile beats coating in oil since the metal seems to breath the stuff in almost.

I polished the inside of my compressor and venturi tunneled my turbo intake while mine was apart. Not a bad time to do things like this since its all blown up in front of you. Same with the idea of going to a 360deg thrust bearing if you can afford it....

What tools did you need to rebuild the sr T25? I want to rebuild mine soon.

just some basic Cresent wrenches.. I took one apart before.. never got around to putting it back together though.

When rebuilding a turbo. Everything should be measured to check clearances.
As in with calipers and a bore mic. If the turbo had ecessive shaft play, there is a possibility that the turbine side piston ring will not seat properly, due to the shaft making its own groove. Same with comp. side. Although, more likely on turbine.
The journal bearings inner diameter should be no larger than .003 of an inch clearance when compared to the diameter of the shaft. As with the clearance from the outer diameter of the bearings to the diameter of the bearing housing bore, where the bearings sit.
There should be no more than a tiny gap between both piston rings. (comp side and turbine side) You should only be able to see this gap when puting the rings in by themselves where they sit in the seal plate and bearing housing and looking through them in a light. You will see a gap. If there is a noticably large gap.. this is a big sign of bad clearances.
If these clearances are any larger than posted here, its time for some more new parts.

I do not think this is a very good job of showing how to rebuild a turbo. A lot more needs to be added. Half the parts that should be replaced and checked are not even talked about or explained. And other parts are not explained correctly.

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WD

Truth is Treason in the Kingdom of Lies - Ron Paul

If that's the case, please specify. A more comprehensive approach to a DIY rebuild would be quite helpful for all us NICOnauts.

- Bench vise
- 13mm box wrench
- 8mm box wrench
- T15 Torx driver
- Scribe
- Snap ring pliers
- Rubber mallet
- Ballpeen hammer

Other helpful items:

- Liquid Wrench
- Orange Degreaser
- Synthetic Motor Oil
- Drip Pan
* "Leverage" tubes (1/2" - 1 1/2" x 12" metal pipes)

* Allows for more torque on the box wrenches when removing stubborn turbine bolts!

WD