AHU LR Pump ALH hub shredded timing belt

[jhax]

Hey all,

I am getting closer to giving up. After 2 turbo failures, the last one being a manufacturing defect, and a shredded timing belt on my way in to work this morning (less than 200 miles driven) I'm getting tired, as is my wife, who is REALLY tired of this saga. I'm not sure where I am going wrong. I didn't machine the outside convex side of the alh hub because it was not interfering with the timing belt. I assumed that the mk4 hub also didn't need machining, but maybe I was wrong? Does anyone know of any other reasons why this would happen?



Thanks,
Justin

[fatmobile]

 On the old 1.6d, sometimes the belt would track to the outside if the bushings were worn.
 The cure was to lift the back of the pump.

 Looks like yours is tracking the other way so maybe putting some shims in the pump mount to lower the rear of the pump would help.
 Glad you didn't lose enough belt to hit valves.

  So you are thinking the sprocket or hub need machining because it's an AHU/ALH hybrid?

[jhax]

[ORCoaster]

Looks like an alignment issues to me.

Did you idle it and rev it once replacement was installed.
To test the tracking?


i always do that when I pull a pump off.

[fatmobile]

I don't know of any belt adjustment that is available on the ALH pump bracket.
 The 1.6 has the 2 bolts behind the pump.
 So all I can think is shims that would lower the rear of the pump.

[jhax]

I just saw the service bulliten about the bracket adjustment last night! I didn't even know that was a thing!

[jhax]

I widened the two holes closest to the sprocket a smidge and attempted to pull the bracket upward while tightening and it seems to have made it worse. The belt now travels way inboard within a few totations. How wide do these holes need to be and is it worth widening the hole in board the motor as well? Should I be using a bry bar to hold the bracket tight upward?

[fatmobile]

Just took a look at an AHU bracket.
It has 4 bolts holding it to the block, behind the pump.
 The two near the belt are above/below each other.
The other 2 are beside each other.
Because the bracket is different on the AHU,
 I was thinking shims somewhere
maybe between the pump and the mount would adjust the angle of the pump.
But I can see how widening those 2 holes might allow you to change the angle of the pump.
So you are raising the front of the pump, and it's doing the opposite of what you want
 Try moving it the other way and see what happens.
 I could be wrong.
I remember it as the common problem was the belt would run away from the engine.
 The common cure was lift the rear of the pump.

When the belt was running toward the engine, that was less common and the cure was to lower the rear of the pump.
 And that is more difficult on a 1.6 because there isn't an alternator bracket to pry against.
Basically by raising the front of the pump you lowered the rear.
 Unless there is some weird physics going on that I can't see.
And since your belt was running toward the engine, that would seem right to me.

 But maybe I have it backwards.
Trying lowering the front and see what happens.
 The fact that it did affect the alignment, even though it wasn't in the right direction, gives us hope.
I did have to use a pry bar on the 1.6 bracket.
 The other 2 holes might need to be widened.