inlet thread diameter and pitch

[itsacrazyasian]

I'm doing a injector pump in my friend's 87 6.9 F250. Be bought a cardone pump off rock auto. Already put the new pump and lines in. Trying to install the rear inlet fitting and it seems the threads are different. I already tossed the core back in the box and he shipped it of, but the fitting i took off inlet looked to be 1/4 npt. The return fittings fit just fine...

What gives? I looked on my truck and the inlet fitting adapter looks different... I'm not taking my pump out just to check though. Figured i'd post up. sure someone here will know.

 

[icanfixall]

If your posting about that silly brass fitting that has an o-ring and it screws into the back inlet of the injection pump. The threads are going to surprise you. They are 1/2x20 national fine machine threads. Find a 1/2 inch national fine thread bolt and test it. This I know for sure.. I took that brass fitting to mike aka knuckledragger. He hhas a machine shop with all the neet tools for measureing thread pitch and such. We were both amazed at what we found.

 

[itsacrazyasian]

Yippee, the new pump does indeed use the oring fitting. I had an extra in my toolbox and it does fit. The fitting on the truck was a 90 degree 1/4npt on one end and the typical international olived fitting on the other. So now i gotta figure out how to go to the filter head, or atleast to 3/8 hose. Gonna hit the plumbing shop up here in a little bit.