After washing and bead blasting the wastegate valve
mechanism may remain seized or stiff to operate. If so,
soak the mechanism in penetrating oil for approximately
20 minutes or a period of time recommended by the oil
manufacturer.
Access to the valve mechanism via the turbine housing
outlet can be restricted but, with care, soaking with
penetrating oil is possible.
HX25/25W/27W Service Repair Manual Turbocharger Service and Overhaul
5:10
Check the wastegate lever arm for evidence of rubbing
or cracking. Check the lever arm pivot for evidence of
fretting damage, wear or cracking. Check the lever arm
for cracking and or misalignment due to mechanical
damage.
Replace with a new turbine housing if damage is
visible.
Radial cracks can occur around the valve seat when
the turbocharger has been abused overheated. Use a
torch to inspect for cracks when visibility is restricted.
Caution
Extra care must be taken when attempting to free the
valve mechanism. Any damage will result in the
replacement of the turbine housing.
Clamp a pair of mole (vice) grips to the lever and gently
apply pressure to rotate the lever arm in an arc.
If this process does not free the valve mechanism, a
new turbine housing must be fitted.
Caution
If the wastegate valve mechanism shows any fault, it
must be replaced. Using damaged turbine housings
will lead to inferior performance of the turbocharger,
and risk of irreparable damage to both turbocharger
and engine.
Warning
Always wear safety glasses.
To Next Page