300 tdi turbo system - How does it work?

[bambamjj]

Hello all

I know why a turbo does what it does but can any one explain clearlyof give a a flow diagram of how it works, from start to finish to end up with more power.....

Daft question i know but would like to know more about what the purpose of various components are, who actuates what etc.  :oops:

Dont boot me off the forum  :lol:

[karlo]

http://auto.howstuffworks.com/turbo.htm

[diggerdog36]

Thats pretty much it, a turbo uses exhaust gasses to spin a turbine, which is connected to a centrifugal compressor via a shaft, the compressor sucks air in from your intake, compresses it and squeezes it into your inlet manifold then into your cylinders.  But as hot gasses dont combust as well as cool gasses the compressed gas is sent through a heat exchanger (your intercooler) then into your cylinders.
 Its then mixed with fuel, compressed further by your pistons, and goes bang, it then goes out the cylinder via the exhaust manifold, down through the turbo turbine, which it spins up, making the compressor spin and the whole process starts again!!! 

[bambamjj]

Thanks for response, but was thinking how this all works with the injector pump, turbo boost etc.

it is so i know how the plumbing works for all the smaller pipes and understand more the reason behind moving the boost pipework to the inlet manifold area

[peasey]

the small pipes are for the wastegate, basicly a stop switch to stop the turbo producing to much boost,without the wastegate its going to keep trying to boost more and more until it melts.the reason that its moved is that the wastegate stop switch thingy is very close to the turbo and keeps this at around 14psi,now by the time its been moved all along the pipe work(the big ones) its probably lost a couple of psi say its now at 12psi thus giving you less power.If you move the stop switch pipe(thats the wastegate sensor)nearer to the engine valves the turbo will continue to boost until 14psi is reached there so its probably going to be boosting at say 16psi at the turbo then loosing the 2 psi along the way and giving you 14 psi at the valves,well thats my understanding of it anyway.Its a shame that you dont live nearer because i have been looking at mine today and when i find my banjo bolt that i have put in a safe place im going to do it.sorry i havent got a diagram but it looks real easy ignore the one that goes to the injection pump and things become clearer.

[stageonesimmo]

The pipe that goes to the FIP is there to allow the amount of fuel being injected into the cylinders to be varied in accordance with the amont of boost being produced - no point in bunging in loads of extra air (ie boost is compressed air - this means more oxygen) and then leaving the same amount of fuel - the more boost you have, the more fuel you want in the cylinders to make use of it.  This is done by the boost pushing on a diaphragm which pushes the fuel stop pin down as boost increases, allowing more ful to be injected.  Simply put.

[RichardM]

But as hot gasses dont combust as well as cool gasses the compressed gas is sent through a heat exchanger (your intercooler) then into your cylinders.
  

Not quite, when the turbo compresses the air the temperature goes up and the volume goes up, cooling it also reduces the volume, allowing you to get more air in and if there is more air you can burn more fuel and if you burn more fuel you get more power out

see http://en.wikipedia.org/wiki/Charles%27_law