KO3 turbocharger

[silver123]

Hi, my question is not really related to tunning area, but I would like to know how all the inputs and outputs of KO3 turbocharger are connected - I don't mean compressor and turbine inlet/outlet but shaft oiling connection, wastegate connection, blow off connection...

Below is some picture of KO3 turbocharger, where you can see more than 2 openings. I will say than plug 1 and 2 are used for shaft oiling, but don't have clue what are other two openings for.

Also on any gasoline engine turbocharger picture there is any blow off valve. Does this mean that blow off valve is a separate part? Is blow off valve in any way conntroled by the ECU or is just a mechanical valve?

Then as read wastegate valve is air pressure controled via N75 solenoid valve that is electricaly controled by ECU that among other inputs also uses MAP sensor readings to determine the necessary boost. But here on this picture wastegate is connected directly to compressor high pressure outlet. Is this just the case with new parts and wastegate is really connected to the N75 or can some turbos have mechanicaly conttroled wastegate?

aslo some simple turbocharger schematics

 

[mrwookie]

In answer to your questions the openings and oil/water feeds & returns and as for blow off valve's the 1.8T's don;'t have these but rather have a recirc valve which dumps the air back into the TIP rather then dumping to atmosphere as a blow off does. This is controlled via a vac nipple on the throttle body.

Finally as for wastegate this is internal and controlled via Acuator which in turn is controlled via N75.

Someone please correct me if I'm wong.

 

[ibizacupra]

1-water
2-oil
3-blank (water)
4-not shown is oil drain

 

[silver123]

thanks both for answers, but I don't really understand all so please coment/correct my understanding.

So basicaly all turbo or super chargers must have some kind of shaft oiling and so does KO3. Openings 2 and 4 are then oil inlet and oil outlet - that is probably the engine sump oil that aslo cooles down the shaft and bearings as engine oil is normaly aslo cooled via oil to water heat exchanger? Openings 1 and 3 for water are not used (not in VAG 1.8T applications)?

Wastegate valve is mechanical valve that is feed with high pressure air from compressor stage of turbocharger, this pressurised air goes throug N75 EM valve. EM coil is electricaly conntroled by ECU. One of the most imporatant data to determine the output signal to EM coil are MAP readings.

QUESTION: can wastegate be directly connected to compressor as seen on above pics and engine will still work well (not 1.8T that normaly has N75 valve but generaly if you add a turbocharger to NA engine)?


I found definition for blow off valve on wiki and rely on your statement it is incorrect.
So 1.8T really has a "recirc valve" (throttle bypass as named on the schematics), that bypass high pressure air from compressor outlet to compressor inlet (this happen when you release gas pedal after high compressor RPM) and it is completly mechanical (no ECU controling)?

Just currious, what is POP OFF valve then, as wiki says it is the valve that lets the pressure to the atmosphere.

QUESTION #2: how is PCV (positive crankase ventilation) system connected in 1.8T? I pressume that a rubber pipe is connected to the opening after the throttle plate where low pressure (vacum) is and goes to the crankcase and the other rubber pipe goes from the other side of the crankcase via one way valve to the other side of the throttle plate where higher pressure is.

 

[ibizacupra]

water cooling IS used on vag 1.8t applications

why all the questions?

 

[silver123]

water cooling IS used on vag 1.8t applications

why all the questions?

the questions are because I want to understand how 1.8T works (hope it is not disturbing and I know this topic should't be really here).

Why does it need water colling since oil has basicaly same temp and how can water circle if there is only one connection (you said that other is blank).

Still don't know about compressor bypass valve...

 

[ibizacupra]

water has more than one entry, it has 3... one of which is blanked depending on fitment.
water cooled is improved cooling over oil.. oil temps will run higher than water temps, its done for increased reliability of the bearing assembly..
this is not 1.8t specific, but turbos generally

early turbos were not water cooled chra's, modern ones generally are, but not exclusively.

oil is the lube and the coolant on oil only ones

 

[silver123]

water has more than one entry, it has 3... one of which is blanked depending on fitment.
water cooled is improved cooling over oil.. oil temps will run higher than water temps, its done for increased reliability of the bearing assembly..
this is not 1.8t specific, but turbos generally

early turbos were not water cooled chra's, modern ones generally are, but not exclusively.

oil is the lube and the coolant on oil only ones

How many connection KO3 then has?
2 for oil (inlet-outlet)
3 for water (inlet-outlet-blank)

Together 5?

How long would tubo work if it won't be cooled with water? Have the normal time? Less?

 

[1.8t20v]

How many connection KO3 then has?
2 for oil (inlet-outlet)
3 for water (inlet-outlet-blank)

Together 5?

How long would tubo work if it won't be cooled with water? Have the normal time? Less?

i used to run rs turbo and cossies without being water cooled, seemed ok.
early series 1 RST's were non-water cooled as std.