davek0974

Well-Known Member

• Jul 21, 2010

• #1

Hi all,

just got my replacement turbo (2nd hand) and thought i would check the wastegate to ensure its not been tampered with and would blow the lid off my disco when i fire her up !

My knowledge is limited but i presumed that as i need 12psi max boost, the wastegate actuator would start moving at around 12psi???

I checked it on our air bench at work and nothing happens until it gets to about 24psi when it starts to move.

Is this normal or do i now have the wrong turbo??

The unit itself looks correct, its a garrett t250-04 ERR4893

Thanks
Dave

 

davek0974

Well-Known Member

• Jul 21, 2010

• #2

Ok, yes you can, spoke to 3 recon guys on phone and the settings are:-

Pressure 17.9psi to 18.9psi should give an actuator rod movement of 0.38mm.

Basically was advised to stuff 18psi up the actuator and set the rod so that it 'just' moves as the pressure is applied / removed.

The unit i received was higher so i've set it this way, we'll see.

The higher pressure setting on the actuator is to allow for pressure loss/back pressure from the pipes and intercooler etc.

Note that these settings are for a Garrett T250-04 turbo on a Disco 1 300tdi only, and of course, don't take my word as gospel as its not my fault if your lid blows off

 

davek0974

Well-Known Member

• Jul 21, 2010

• #3

Ok, now i'm baffled, got a copy of RAVE and it says to set the rod at 12psi so thats what i'll do. Better too low than too high.

 

K

kingsonlim

New Member

• Jul 21, 2010

• #4

for a 300tdi, the waste gate should operate at around 12psi, which is about 0.8bar...however, boost gauge I have on the vehicle is showing 1 bar at full accelaration, which is about 15psi. I would suggest setting the waste gate to between 13 - 14 psi, and fit a boost gauge to monitor. Then re-adjust up or down if you so wish.

I fitted a boost gauge to monitor the performance of the turbo, and indeed found out about leaking manifold gasket when the pressure dropped.

 

P

pauli

New Member

• Jul 22, 2010

• #5

As a matter of interest King how did you fit your guage pipe.People seem to do it different ways
One suggestion was to attach the guage to the manifold that the intercooler out connects to to give a true pressure reading
Ta
Paul

 

davek0974

Well-Known Member

• Jul 22, 2010

• #6

I tee'd my one in at the turbo outlet where the injection/wastegate pipes go.

 

K

kingsonlim

New Member

• Jul 22, 2010

• #7

2 ways:

- as Davek stated...a tee at the injection/wastegate pipes, but found the pressure to be a tad lower if connected here (0.75bar vs 0.82bar at manifold).

- however, I've added a new outlet at the manifold. There's a pressed in cap at the end of the inlet manifold, facing the cab. Drilled a hole, fitted a 3/8" tail fitting, then connect the hose onto the boost gauge.

I suppose the boost gauge reading doesn't have to be accurate, afterall, the boost gauge is there to tell me if there's a leak or if the turbo is working properly. As long as you've taken a 'benchmark' reading after fitting the boost gauge...then any drop in reading below that signals a leak somewhere. I also opted for clear hoses, as I can see if the crud etc eventually gets in there, it would be time to take it out for a clean.

 

davek0974

Well-Known Member

• Jul 22, 2010

• #8

I have read a reply somewhere that someone had plumbed the wastegate pipe into the plenum too so that the boost was controlled right at the intake.

I dont know if thats a good idea or not, surely if it was then they would have been built like that. One downside i can see is that if the intercooler blocks up, the turbo will be working its arse off trying to raise plenum pressure.