I have just recently found out that my twins are shot, so I'm in the market for a new (used) set.

I am doing this thread primarily for another member on the forum. He is going the LS1 route =( all the power to him though. I am looking to buy the twins from him, but I first want to see the condition of the turbines first.

I figured I'd post it on here so others could follow my write up as a template. I am in no means a mechanic, so the following is merely a template to follow. The steps I took worked for me, but possibly not for others, so ATTEMPT AT YOUR OWN RISKS!!

This will also apply to wastegate porting, since many people are somewhat intimidated by taking apart the turbos.

Oh, and by the way, my photography sucks, so no dissin! Lol.

Hope this helps... enjoy.



Starting point: the twins nearly stripped down, ready for seperation:

 

Start by removing the e clips on the actuators. Remove the actuator bar from the flapper pins (for lack of better terms)

 

That is the cleanest set of blown twins I have ever seen.

 

From this point on, we are going to focus on the primary turbo. When I say remove "x" I will be referring to the primary side of everything.

Remove the first water line bolt. 19mm. Make sure to retrieve both washers.



Here it is removed:

 

Flip the whole assembly over and do the same:



The bolt removed:

 

Remove the oil line. Again, account for the washers. 12mm.



The bolt removed:

 

Remove the 4 manifold bolts. I used WD40 to loosen these up. Careful not to strip anything. 13 mm.



Another on this side:



Flip the assembly over and do the same.

 

You should now be able to separate the primary and the exhaust outlet from the secondary.



Can you tell that I cleaned one of the assemblies before?

 

So you will be able to access other bolts, you will need to remove this return line. 10mm.



Here it is removed:

 

Edit: Whoops! Double post

 

There are now 6 bolts that need to be removed to remove the hot side's snail. I used WD40 again to help with the process. I used extra caution and loosened these using the star pattern, the same way you do wheel lug nuts. 10mm.



Removed:



Just cuz:

 

This was my best method for removing the snail: I used a mallot and lightly tapped it loose in a couple areas until it came free. If there is a better way to do this, please chime in and enlighten us.

 

Carefully remove the two sections.



Inspect the turbine. If it looks anything like this, then its shot.

 

Aaaaaand finally, for those of you that want to port your wastegate, this is your step.





I did a really moderate port on mine. I know i could probably go a tiny bit larger, but, since my twins are now non operable, I figured I wouldn't bother going any larger. Rule of thumb: diameter should be no larger than 1.24" or the way I measured, the flapper should barely make a seal. You really cant screw this one up, unless you go way overboard. I used a stone grinder (from Home Depot for 7 or 8 bucks) on my drill press. On the fastest setting, it took me about 35 - 40 mins. Make sure to thoroughly clean all shavings before reinstalling.

 

Um...yeah, I guess you say that exhaust turbine is "shot"...

 

Reinstall is of course just a backwards disassembly. Account for all the appropriate washers and torque specs.

Hope this helped for some of you.

Those that know a considerable amount more than me, feel free to add to this.

Well its off to work. I'll be happy to respond to any comments or q's when I get back.

This thread just doubled my post count! Whoot! lol

 

Lol. I cleaned the primary when I first took it apart. The secondary is still a lil messy.

 

Care to elaborate?

 

mileage?

 

I believe he's referring to these pictures. The wheel deff needs to be replaced, there's no fixing that.

 

Yep. Pretty obvious that particular exhaust turbine ingested something it didn't like...

 

A little JB weld on those veins and it will be good as new....

 

Awesome thread for us noobs Thanks!

 

thank you for a good write up

 

So Did You Fixed It??