Teach me about broken turbochargers| Grassroots Motorsports forum |

Woody GRM+ Memberand MegaDork
8/22/12 11:29 a.m.

As you may recall, about a week ago, I dragged home a 2005 Subaru Legacy GT with no engine (big mistake). It's gone now (I broke even), but I did hang on to the bad turbo and the intercooler.

I like to take things apart to learn about them. I've owned turbo cars before, but this is the first time that I've had my hands on a turbo that's been removed. It's an IHI and the shaft is obviously broken, even though it had less than 10k miles on it. The engine had an oiling issue and this was the fourth turbo in the car's 116k miles.

So I'm going to take it apart and see what's inside. It looks fairly straightforward, but is there anything I need to watch out for as I disassemble it? Can it be rebuilt or is it a goner?

Keith GRM+ Memberand MegaDork
8/22/12 11:32 a.m.

It's not something you can rebuild, but it can be rebuilt. It's unlikely you have the ability to balance it when you're done

If you want to take it apart to see the little parts inside (hint: bearings), have at it. If you want to have it rebuilt, I'd probably leave it alone. The cool stuff is in the housings, not the center section.

Woody GRM+ Memberand MegaDork
8/22/12 11:35 a.m.

Thanks Keith. Since I have nothing invested in it and because I have no use for it and it has relatively little value as it sits, I'll probably just tear it down out of curiosity. Had I kept my unopened copy of Maximum Boost, I probably could have just looked at the pictures.

DaveEstey Dork
8/22/12 11:36 a.m.

It's not a ball bearing turbo so it's not terribly interesting to dig into the center section anyway.

16vCorey UberDork
8/22/12 11:37 a.m.

It can be rebuilt, but I bet the shaft and both wheels cost about as much as a reman turbo.

When the shaft isn't broken it's a pretty straight forward process. Mark the wheel's relation to one another, take the nut off (generally on the compressor side), take the shaft out, put new seal rings on the shaft, put new bushings in the housing, and put the shaft back in. If you're going to have the shaft/wheels rebalanced you don't need to mark them before you take them apart.

JohnInKansas HalfDork
8/22/12 12:13 p.m.

+1 to all of the above.

Pull it apart or cut a quadrant out of it for a sweet "cutaway-view" paperweight.

GameboyRMH GRM+ Memberand PowerDork
8/22/12 12:27 p.m.

Wait why was getting the engineless Legacy a mistake? I've been looking for an engineless GC Impreza...

N Sperlo PowerDork
8/22/12 12:30 p.m.

I need a new paperweight.

Keith GRM+ Memberand MegaDork
8/22/12 12:30 p.m.

BTW, this book has a section on rebuilding turbos as well as failure diagnosis.

http://www.amazon.com/Turbo-Real-World-High-Performance-Turbocharger-S-/dp/1932494294

Ojala GRM+ Memberand Reader
8/22/12 1:23 p.m.

I don't know of a reputable parts source or rebuilder for IHI turbos. When you add that to the need to balance the turbo as a unit it doesn't make any sense to buy one used. This is reflected in the sales price of used or worn IHI turbos.

To my line of thinking, why not just buy a component balanced MHI for which you can get actual factory parts and can be easily rebuilt?

92CelicaHalfTrac MegaDork
8/22/12 1:44 p.m.

I think a broken IHI would have been the last thing i would have kept off that car.

Vigo SuperDork
8/22/12 10:11 p.m.

First step to disassembling turbocharger: To keep in mind that the shaft nut could be threaded in either direction depending on turbo rotation. It's fairly easy to snap the end of the shaft off if you go right at it with a power tool like a small cordless impact, etc, without noting the direction of the threads.

Woody GRM+ Memberand MegaDork
8/23/12 3:02 a.m.