Waste gate shaft not moving...
 

I have an '87 300SDL that I've been working on - had a plugged up exhaust that I recently relieved.

While I had this area of the engine apart I tried testing the waste gate - I applied pressure using Mighty Vac hoping to see movement in the rod that connects to the waste gate. I heard a good pop when I applied pressure but the rod never moves! It seems stuck in place. I tried tapping on it with various instruments trying to get it dislodged but no joy... I suppose the risk form that condition is that the turbo can over-boost the motor....

What do I need to try to get it to move?!

how much pressure were you able to apply with you mighty vac,its going to take almost 12 psi to move the wastegate . Don

I didn't measure it - tThe MightyVac doesn't show positive pressure on the dial... only the Vac (mmHg) so I don't know for sure, but I pumped the vac 'til it couldn't go anymore... felt like I've reached its capacity. I could put a "T" in there and check accurately with a pressure guage... Will need to try that.

Meanwhile - shouldn't I be able to move that wastegate shaft by hand? It sure feels immovable to me...

I never tried moving one by hand but realize that Vac is the opposite of Pressure


You need to be putting 12psi or so into the wastegate hose not vac.

Correct....

The wastegate valve stem is hollow for cooling, which creates a pressure of 'killer' bleed that you have to overcome.