Timing Belt snapped two times

Ok so i have a 2002 jetta 1.9 turbo diesel. I was driving and the timing belt snapped. At the time i did not know that was the problem, took it to a mechanic and he found the problem. I had the head rebuilt, and timing belt and water pump replaced. I had the car back for two weeks, and the belt snapped again. The mechanic looked at the head again and the lifters were locked solid. Even after applying heat to them they would not budge. It was not getting oil to the top of the cam. Does anybody know what can cause this? I plan on getting rid of the car for scraps, but just curious as to what can cause this to happen. Any bit of information can help.

Thanks,
Ben

Maybe you have loose valves that keep on damaging the pistons. That instance may damage timing belts.

I'm also not sure, but I've read from one article that you should also have your valves replaced when you had your water pump and belt replaced so that they're compatible. I'm just not sure. It could also be the car parts that were used as replacements.Maybe their of low quality.

Sorry, I haven't experienced this so far so I could only give you advices from other people.

Hello, Your problem is not snapping timing belts. That is a consequence of lubrication failure and I promise it will reoccur .

Before you suffer permanent engine failure you need to address the lack of lubrication, and why your low oil pressure system is not functioning. If it was my engine this is how I would proceed.

#1 Turn the key to the run position, but do not activate the starter. You should be able to hear your in tank fuel pump start, run for about 5 seconds , then it should shut off. The low oil light should come on and stay on.
#2 Remove the oil pan. First question is the pump pick up screen clean? By any chance is there a foriegn object such as an oil bottle seal loose in the pan? Are all the bolts on the pump tight? Now that I am that far I would pull the pump and check that it is within specs. Making certain nothing is stuck in the pressure relief valve.
#3 With the pump out of the way, Sad

and knowing I have had 2 separate lubrication failures A WISE IDEA is to look at the con rod bearings one at a time. Very loose con rod bearings can cause oil pressure loss.
#4 If all is well in your bottom end and the bearings are fine , then the next area to look at is the oil filter. On extremely rare occasions with other problems a filter can plug.
#5 Did your mechanic install the head gasket correctly? MMMM
#6 Are your turbo bearings failing and to much oil bypassing them?
#7 How much oil pressure <with a guage> was present after the rebuild?
I am very suspicious of this. My opinion is this. I warranty my work . I am a journeyman, although not an auto mechanic. A journeyman mechanic will sometimes make mistakes, however even though I do occasionally make errors I repair them at my cost. I think your mechanic only fixed the symptom, and now should at his cost repair the problem.
If you really want to scrap the car, sell it at the scrap price to me. I have 3 decent motors I can retro fit. My number is 250 962 6529 allan