Cm870 VGT issue

[Rawze]

(11-06-2018 )Chamberpains Wrote:  Im wondering, did you guys never pull the actuator off and move the VG ring manually?

I did that while it was here. Did not have a reference when I did so, but later got a chance to check another one.

The actuator arm was about 2 - 3 x more stiff on his than one that I tried several days after he left. I talked to YTS turbo about it and he said that he has seen that before. He said that some of the older turbos have a fixed ring in the exhaust housing for the VG blades to go into instead of a floating one. His Marek's was this older style. What happens with them sometimes is that when installing one of that type, the exhaust housing - to- main housing joint can get tweaked a tiny bit, making the VG blades drag against the slots they protrude through in the exhaust housing. He said it is not unusual to have to loosen the v-band clamp that holds the exhaust housing and move the main housing about 1/8" back and forth to find the place where it frees it up and centers it.

That is the most likely reason why it was stiff and would jump instead of operate smoothly. It just needed a bit of tweaking to free it up after it was put back on the truck, as it was this older style of turbo housing.