Turbo question

[Steve_D]

In this pic there is an actuator.
I know very little about turbos but assume this is some sort of vacuum unit.



Should it be possible to push this through its range of movement by hand?

If so then my one is FUBAR.

If it is jammed then what would the symptoms be?

Thanks
Steve

[226bhp]

You probably mean the wastegate actuator and It depends how strong you are. There should be quite some resistance and it's pressure activated not vac.
If you can put some air pressure to the supply pipe it may give some idea if it leaks or operates the wastegate.

[Steve_D]

So how much pressure?
Don't want to blow it inside out by putting the workshop airline on it.

Steve

[TheEnd]

It depends on the turbo, but 1 -1.5 bar should move it if it is a diesel.


edit, scrub that, that would be for a "boost" actuated wastegate, a vacuum operated one would need vacuum.

Simple boost operated turbos would have a short line over to the compressor side. Vacuum ones would go to a vac solenoid.

Edited by TheEnd on Wednesday 6th August 21:04

[anonymous-user]

Find an open ended spanner that "fits" over the square wastegate actuating arm that sticks out of the turbine housing (from memory, think it's 12mm for Garrett blowers), use this to carefully open the wastegate (the actuator rod extends out of the actuator capsule. This will tell you if your system is jammed, corroded or sticky. It should move relatively freely.

Then using an airline with pressure regulator, start at around 5psi, apply to actuator capsule. Any leaks can be a failed diaphram, and for most road cars, something between 7psi and 12psi applied should pretty much fully extend the actuator.

Also check for cracking of the wastegate "penny valve" and its seat, by looking up the turbine exit and opening the valve so you can see the seat

ETA it is highly unlikely to be vacuum operated if it is from a diesel, what with them not having throttle plates!!

[stevieturbo]

Max_Torque said:

ETA it is highly unlikely to be vacuum operated if it is from a diesel, what with them not having throttle plates!!

Most diesels, especially VNT use vacuum to control the wastegate Max ( unless it's a modern electronic unit of course )

Just like their brake servos use vacuum...

But that one dos look like a pressure operated unit.

[Steve_D]

Sorry fail on my part.
Car is a 97 Peugeot 306 1.9 diesel.

Steve

[littleredrooster]

stevieturbo said:

Most diesels, especially VNT use vacuum to control the wastegate Max ( unless it's a modern electronic unit of course )

So how does that work when a diesel runs on open intakes? No vacuum. Ever.

stevieturbo said:

Just like their brake servos use vacuum...

...but driven by a cam-operated vacuum pump...

[TheEnd]

There's a vacuum reservoir, and this is running though a solenoid controlled by the ECU.
Almost all the BMWs are like that, save for the old "passive" turbo on the xxxTDS's (as opposed to xxxD's), and the modern ones usually have electronic actuators.

[stevieturbo]

littleredrooster said:

...but driven by a cam-operated vacuum pump...

You've just answered it.

Whether cam, crank, belt, alternator, diesels use a vacuum pump. This vacuum is used for a hell of a lot more than just brake assitance these days.

So there is vacuum...always.

[slinky]

stevieturbo said:

So there is available vacuum...always.