Injector O-Rings?

[sacmame]

I just changed the head on the passenger side, I switched over all my stuff from old head (injectors, rockers, etc). I didn't change the injector orings when I swapped them, they looked ok to me, and the engine only has around 66,000miles on it. After getting it running it was hard to start (took awhile cranking, I figured it was just air working it's way out of the HPOP system. I drove it for a while today, and it's still hard to start (cold & hot) takes like 10 seconds of cranking before it turns over. If i shut it off and restart it right away it's fine, but if a wait like 5 minutes it's hard again.
I noticed after I turn it off a noise coming from only that head/side. It sounds like air or pressure leaking/bleeding. Kinda a hissing sound. Could this be the high pressure oil leaking from around the injector orings, and that's why it's hard to restart since it need to rebuild the oil pressure?


thanks

[96F350KID]

When ever you remove the injectors its always a good idea to replace the O-rings on them. On customer trucks it normally takes driving 6 miles round trip on the interstate and a good 5 cold starts and 5 warm starts before all the air is out. Now I dont want to make you sound stupid but when you heard this noise was it right after you shut the truck down with the A/C ON? Drive it with the A/C OFF and see if you still hear it. The sound might be the pressures equalizing across the orface tube in the A/C line which is right next to the passenger side head.

[sacmame]

Hi, thanks for the reply. You were right, it just needed to be driven. Starts right up now, better than I think it ever has! lol As far as the hissing sound, you might be right, and I do feel a ittle stupid, I wasn't thinking about the ac being on, but the defroster was on, so I think you were right, I turned off the heating/ac and the noise stopped.

I ordered injector O-rings anyway. Figured be good to have them on hand if I ever need to pull the injectors or it starts acting up.