Archived fuel drain manifold banjos stripped

[d9]

Upon replacing injectors, I stripped a few banjo bolt threads. That was too easy!! Actually, its more likely that the female threads in the injectors are stripped too, (I tried different banjo bolts on the same problem injectors, and to no avail they get stripped also. )



This is actually the second time I've done the injectors-- the first time I suspected a leak from the copper sealing washer at the injector tips-- fuel seemed to be flowing up through the hold-down nut dust boot seals. Now I've learned that the leak in the first place might have been due to overtorqueing the fuel drain manifold banjo bolts. (What is the correct torque for those?)



Does anybody know some part numbers for



1. Fuel drain manifold banjo bolts?

2. Copper "U" washers for banjo bolts?

3. . 5 mm copper washers for injector tips?

4. Injector hold-down nut dust seals?

5. Injectors?



On my third try, I don't want to mess around with old parts!! What is the fastest way to order parts online?



I hope #5 is not necessary, but with stripped threads inside the injectors, do I have a choice? I'm no machinist, but is it possible to use a hardware store tap and die set to fix the banjo bolt and injector threads?



I'm definitely a newbie here-- any help would be greatly appreciated. My truck's a work truck, so I don't know what I'm gonna do come tuesday. Thanks again.

 

[Sticks]

Originally posted by d9





I hope #5 is not necessary, but with stripped threads inside the injectors, do I have a choice? I'm no machinist, but is it possible to use a hardware store tap and die set to fix the banjo bolt and injector threads?



I'm definitely a newbie here-- any help would be greatly appreciated. My truck's a work truck, so I don't know what I'm gonna do come tuesday. Thanks again.

If this were just a mounting bolt, I would say yes, you can chase the threads with a new tap. However since this is a VERY HIGH PRESSURE situation, if the injector threads are indeed stripped, you will not get a very good seal since the threads were damaged, and you will be shaving off the damaged part. Never mind the risk of getting metal shavings inside the injector.



I would verify that they are stripped, and if so, replace them. Now would be a good time to get some slightly larger injectors.

 

[d9]

injector threads crossthreaded

Sticks-- arent the threaded ports in the injector body that host the fuel drain manifold banjo bolts part of the low pressure fuel return system?



Even if it was advisable to tap the threads, I don't know how it would be done, considering the threads are only about a half an inch deep.



Anyways-- here's an update: I finally managed to screw the two problem banjo bolts in (anyone know the recommended torque for those?)



All was put back together for a second time, all with used washers, etc. Now about 4 of the six injectors are leaking!!



The leak is not due to bad banjo bolts, but to something down indside the injector bores. I can see fuel and miniature air bubbles leaking up through the hold-down nut dust seals. Any clues as to why this is happening? Thanks

 

[bmoeller]

I've never used torque wrench on the return. Snug is usually enough, doesn't take much.

Sticks-- arent the threaded ports in the injector body that host the fuel drain manifold banjo bolts part of the low pressure fuel return system?

Yes, but it is still pressure. Don't think it is all that much, but still enough to make a mess.



There are "bottom" taps that aern't tapered like the ones generally used. I wouldn't use one. As Sticks said, the potential is there for bits to get in there.