As can be seen from the descriptions and diagrams the gas turbine engine and the turbocharger have a lot in common. The difference is how and where the compressed air and fuel are burnt to produce hot gas to turn the turbine. The gas turbine engine has a combustor. The turbocharger has the engine of the vehicle it is attached to. If we remove that engine and replace it with a combustor of our own design the turbocharger becomes a gas turbine - a jet engine!

Once I became interested in building my own engine I naturally had to find myself a turbocharger. I didn't know anything about them or how much one would cost me. So I took to the local phone book and began calling places, starting with those geographically closest to me. The very first place I called was just down the road and they happened to have an old turbocharger they could sell. I asked the price and some details and said I'd get back to them. I could hardly buy the first one I found now could I? I called around more places and got more quotes and found that the first one I'd had was very reasonable. I called them back and arranged to go and see it.

I must admit I was quite excited when I went to see it. I wasn't quite sure what it would even look like. I'd seen pictures of turbochargers on the Internet before but I'd never actually seen one. I wasn't even exactly sure I'd be able to tell if it was a good one. From what I'd learnt on other web pages I knew more or less what to look for:

+ Very little ( less that 1 - 2 mm) sideways play on the shaft
+ Absolutely no lengthways play on the shaft
+ No visible damage to either the compressor or turbine blades

And this is what I found.