Sealing up an M10 fitting

[HParfitt]

Hi,

She's a leaking. I installed an oil pressure gauge. I decided to use the M10 port on the side of the block in the oil rifle. I ordered an M10 to 1/8npt fitting from fittings and adapters as someone suggested on the board. The port I used is the one above the ecm. The fitting came with a washer and o-ring. The washer against the fitting and the o-ring on after that, on the thread side. I also used some liquid Loctite pipe sealent on the threads. When I installed it, it was leaking. Had it pretty tight. I took it apart and noticed that the steel washer fit was very loose. The threads are actually a larger diameter than the shoulder where the o-ring and washer sit. Also the o-ring was a little thinner than the one on the original Cummins plug. I thought that the o-ring got pushed into the gap between the inside of the washer and the shoulder of the fitting. I decided to try it wihout the washer and used the fatter o-ring from the original Cummins plug. Also put a little more sealent on it. It's still leaking, not nearly as bad but leaking. This is the first time I used a fitting like this. Always used npt stuff. Any advice?

Thank you.

 

[nickleinonen]

i used a copper crush washer on mine and no leaks, but i don't like it... it needs too much torque to seat the washer to seal for the soft cast iron block [i think i may have damaged the threads in the block ] when i remove it to relocate it from above ecm to behind cp3, i will use an oring or maybe a bonded washer. .