Prince autocycle valve

[Ivan49]

That fitting is bad. The threads are cut to deep on that fitting and it does not let the taper tighten down correctly. I would say your choice to use what fitting you want to use as I have many here using reg pipe fitting on my hyd system and they have been on there for over 40 years. To be correct use a hyd reducer bushing as they are made of steel instead of cast

 

[escavader]

I'm fixed I stopped trying to put adapters

 

[escavader]

...put adapters in valve came out with pipe first