About a month ago I had the car tuned and then went to a track day. It was going incredibly well.. at first. It started smoking and then caught fire. I caught it quickly and put it out. Seems the oil feed to the turbo had been disconnected and attached one too many times and was cross threaded and leaking.

Also some of the bolts connecting the exhaust turbine to the CHRA had worked loose. I tightened then up, reconnected the oil feed properly and headed home (some 200Km).

Over the last month I have been working on it intermittently when work wasn't too busy and I haven't been travelling (New Zealand is nice this time of year). I replaced some of the turbine to CHRA bolts and replaced the restrictor where the oil feed connects. I started it up and the turbo span nicely. There was a bit of an exhaust leak where the downpipe connects but I tightened up the V-band.

There was some valve train noise. Turns out last time I adjusted them I mustn't have tightened the lock nuts properly. One was loose and another was missing. I pulled the top end apart and it wasn't there. I pulled the sump and couldn't find it there either. I eventually found it up inside the oil intake wedged against the mesh.

Turning into a saga isn't it! Anyway when I got back from NZ I started playing with it again. I gave the turbo a spin... no I didn't. It was seized.

I started pulling down the hot side and I can now turn the turbo by hand but it is not easy and doesn't spin.

Does anyone have any ideas what can go wrong with a turbo just sitting there? It span nicely last time I started the car but isn't spinning now.

 

Sorry to hear about your troubles. Last time I dealt with a siezed turbo we ended up finding a chunk of an exhaust valve wedged between the turbine wheel and housing

 

my journal bearing turbo will become harder to spin when its sat for a while. I'd presume its because the oil, with the help of gravity, is no longer lubricating the bearings.

 

Doesnt sound too good. Oil contamination could be the cause, or hot oil coking up in the bearings.

 

Just for giggles.

After pulling the valve train off and not finding the missing nut, and noticing the 4 drain holes to the sump I drained to oil hoping the nut would be flushed out. No luck.

I then proceeded to pull the sump and look for it there. No luck.

A thought then occurred to me and I got under the car with a torch and looked up.



Success!

 

I assume as it was running a couple of weeks back and now turns but is stiff it's not a piece of valve or anything solid but more likely oil coked up.

What sort of solvent can I safely use through a ball bearing turbo that will dissolve the oil but not damage anything?

 

Carb or brake cleaner may work. Those would probably be the best for breaking up the oil. No guarantee it would work, but if the turbo is seized no harm in trying something.

 

Carburetor/throttle plate cleaner will dissolve the carbon. May or mat not have a functional shaft seal when you are done.

 

I took it to GCG Turbos where I bought it. GCG stands for Giant Cash Grab.

 

Spoke to GCG today. Seems the turbo has been overheated (again!).

I guess this makes sense when you consider all the overheating problems I have had of late but seriously, last thing I need at this point.