Injector leaking after shop serviced it

[tgblanken]

1985 300D Turbo Diesel 235,000 miles


I had my injectors test at a local injector shop. One of the injectors was low on the pop test (132 bar, rest are 138, 140). So they shimmed the low injector and brought it up to 138 bar. The spray pattern on all the injectors looked great. Surprizingly the shop let me watch as they tested the injectors. I installed them and the car idles smooth but one of the injectors is leaking. Its the one they shimmed. I took it back to the shop they took it apart and cleaned it and tested it again and said it's not leaking on the tester. I installed it again and it leaks at the threads where the injector is put together. The small return lines are new and dry and the high pressure fuel line to the injector is tight and dry. I called the shop told them it was leaking again. They said they could lap the injector parts.

What are my options? Can I just over torque the injector (factory torque is 70-80 Nm)?



The previous owner purchased the rebuilt Bosch injectors from Performance Products in 2002 at 210,000 miles. The injectors have about 25000 miles on them.