Turbo replacement

[3DB]

I have purchased a new Chinese copy of my IHI RHB5 VI58 turbo from eBay and have started preparations for replacing the old one in my Rodeo later this week.

Having degreased the area and removed the heat shields, I was confronted with an interesting bolt arrangement that mates the exhaust side turbine housing to the dump pipe. As you can see in the photo, rather than just a simple hex-head bolt going all the way through it appears to be a threaded stud with a nut on one end.



My fear is that when I start to loosen those nuts, the nuts will come off and leave the threaded stud still connecting the two parts with no way to remove it.

Has anyone else encountered this arrangement and how did you deal with it?

(Thanks again to Cade for the tips already provided from his experience recently having done the same thing with his Mazda)

[Captaincademan]

Happy to help out where I can. Odds are once the nuts are removed, it will be a girl.

No seriousely, it should come apart with maybe a tap from a resin head hammer or a timber drift. You might even find the studs come out of the casting with the nuts still attached. Don’t worry this is common. The central part of the stud will be a blank with a thread on each end. You might find you need to separate the dump pipe from the exhaust as well in order to remove the whole assembly as there won’t be enough room to manoeuvre the turbo from the dump pipe given the stud length. I would suggest this anyway, as you can take the opportunity to clean the carbon from inside the dump pipe. If you intend to do a cat delete (which I don’t advocate publicly) now is the time as it will probably be just downstream of the dump pipe where the exhaust is still hot.

Take care to keep the turbo internals clean whilst installing. Very important to Prime the turbo with clean engine oil before starting for the first time.

[3DB]

Thanks once again, Cade.

I don't have a cat in this old girl. Already has a 2.5" straight through exhaust from dump pipe back. Hopefully I can re-use the gasket.

The new turbo came with a little tube of priming oil + a set of what appears to be white cotton gloves!

[3DB]

It took me half a day to get the old turbo out today. I was close to having to remove the who exhaust system to get the dump pipe off.

One of the studs on the dump pipe snapped off when I tried to remove the first nut.

Another one stripped the threads off the end.

All 4 are stuck in the old turbo, so I will have to get 4 new ones anyway.

Fun and games.

[tillyfromparadise]

Exhausts and old plumbing- two joys of life

[3DB]

It is all back together and running. I think it took about 20 hours all up, which I still find unbelievable.

The number of times I put pieces together only to find that there is another bit that now won't fit, then pulled it apart again.

The biggest pain by far was the oil drain pipe bolts - tiny little 8mm things that are almost impossible to reach.

A very, very fiddly exercise.

I ended up having to make new studs myself out of M8x1.25 high-tensile threaded rod. Spent a couple of hours and about 10 phone calls trying to track proper studs down in a city of 4 million people with no luck.

Anyway, the results are good so far. Boost builds much more quickly and hits maximum 13.5 PSI at far less than redline RPM, which is a vast improvement.

Cade - I will look at adjusting that boost-compensator spring in the IP next.