mike h wrote:

1990 turbo, inside exhaust scroll. Outside scroll looks 100%. No wheel to
scroll contact.

Mike Harrington

Scott Speirer wrote:

I took my '91 stock turbo unit in 1 1/2 weeks ago to a shop for rebuilding. Should be done
in another week and they quoted me $295.  Not too bad, price-wise, I think.  (Turbonetics
wanted $400.)   I had already taken the unit apart before bringing it in, and the fellow
there was able to look inside the turbine housing.  Mine didn't have any cracks inside the
turbine housing, including the scroll areas.  He was surprized there weren't, saying he
usually sees a crack in that area.  But, who knows how the other turbos he had worked on
were treated, and I also don't know how mine was treated, or how many miles my engine
really has on it.  It preportedly only has 30,000 miles, and taken out of an RX-7 from
Japan.  Even though there were no cracks anywhere to be seen, there was coked oil on the
cone surface of the turbine side of the center assembly.  The rebuilder said that was
normal.

By the way, I had reported several months ago that the water seal on the compressor side of
my turbo had failed and coolant had been leaking out into the compressor housing.  I was
wrong, plain and simple.  I'm sorry that I gave out incorrect information to the group on
this.  The rebuilder said that just couldn't happen because the fluid chamber along the
shaft closest to the compressor housing is an oil chamber, not a coolant chamber.  So, the
corrosive build-up of stuff in the rotor housing probably came from outside the engine.
There are a number of unpleasant images which could explain this, including the car sitting
in a junk yard for years with the hood off, the intercooler off, and the air hose to the
compressor sticking straight up to receive rain water.  Well, I'll find out more when I
take apart the engine.

Any gotches when taking them apart?

I took mine apart with the help of a friend of mine.  All the bolts which were visible were
unscrewed without a problem.  Some were on pretty tight and I had to use a cheater bar on
my wrench to loosen them.  All this was pretty uneventful except for separating the turbine
housing from the center assembly. They're both iron of some kind, I think. They just
wouldn't come apart.  My friend, who was generally familiar with turbos, knew at that stage
if the dissassembly there were no hidden screws or such to be taken out, and these two
pieces just had to be forced apart.  He used a large rubber mallet, hitting the housing at
oblique angles, while applying force to the center assembly at the same time.  It finally
gave and no damage was done.  After these are separated, you can take out the bushings on
the turbine side.

Hope this helps.

Scott

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