VWDiesel.net The IDI, TDI, and mTDI source.
Engine Specific Info and Questions => mTDI Mechanical TDI Conversions => Topic started by: jhax on June 17, 2026, 06:23:05 am
-
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?
(https://www.thesamba.com/vw/gallery/pix/2677648.jpg)
Thanks,
Justin
-
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?
-
(https://www.thesamba.com/vw/gallery/pix/2677717.jpg)
(https://www.thesamba.com/vw/gallery/pix/2677718.jpg)
(https://www.thesamba.com/vw/gallery/pix/2677719.jpg)
(https://www.thesamba.com/vw/gallery/pix/2677720.jpg)
-
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.
-
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.