Greetings,

Yesterday while driving the timing belt on my carburated 1984 B21 in my 240DL let go. I just shifted into fourth gear and it was like someone shut the key off on the engine. I dropped it into third to see if perhaps I lugged it for a second in fourth, as I was towing a small trailer with a barbershop chair in at the time, but it still wouldn't go. I rolled into a parking lot and tried to start the car and noticed a distinctly different sound to the engine. In the back of my mind I thought "the timing belt is shot", but I had literally just filled with gas, so I thought I might have received some bottom of the tank fuel. I cranked it and few times and it still wouldn't go.

Long story short, it wasn't the fuel, a mechanic came and checked it and the timing belt is broken.

Questions:
1) Is the B21 a non-interference engine?

2) How easy is it (ie. how many hours labour) is it for a mechanic to tell if I've bent valves / damaged the pistons, etc

3) What else can expect to have possibly damaged?

4) How many hours shop it take a mechanic to fix this if it's only the timing belt that needs to be replaced and there is no internal engine damage?

Thanks in advance,

Jaak