HMMWV (GM7) Turbo Question......

[HoveringHMMWV]

2007 M1151A1 with original 6.5L Turbo GEP. The truck has zero blow by and only smokes a little black during heavy acceleration. However, I decided to "play" some today and removed the waste gate manifold in order to take a peek at the turbo. Pic included (wet spots are from penetrating oil overspray). The exhaust side blades have no axial play but there is a very small amount of side-to-side (without blade rub). When aggressively spinning by hand, the blades will stop within 1 to 2 full rotation(s). Learning here, but this seems odd. Seems like they should spin more freely (ie. many rotations before coming to a stop)? Any input would be greatly appreciated.

 

[Mogman]

Some radial movement is normal, the oil on the bushings is rather thick when cold and there is not allot of mass there so all that sounds normal IMHO.

 

[87cr250r]

Turbocharger bushings are meant to rotate in the housing. This means there is clearance between the shaft and the bushing and clearance between the bushing and the housing. All of this clearance makes them feel loose. As long as you can't make the compressor touch the housing the turbo is good.

As for the number of rotations, there isn't much mass in the rotating assembly to keep it turning. These turbos use bushings and not ball bearings.

 

[TOBASH]

So you have a properly working truck but you decided to open the turbo just for kicks.

I don’t get it.

 

[HoveringHMMWV]

So you have a properly working truck but you decided to open the turbo just for kicks.

I don’t get it.

Yep. Sure did. I promise that I'll put it back together and that it'll be fully functional.
I'll also know more than I did yesterday.

 

[TOBASH]

Please avoid pulling the IP open.

Just sayin’

 

[HoveringHMMWV]

Please avoid pulling the IP open.

Just sayin’

Already successfully swapped out one of those. Learned enough for now.