Hi folks looking for some help or explanation for the following.

2.0 duratec engine stripped and checked and cleaned. Bottom end all good. Cylinder head sent for strip skim and rebuild. Returned to me fitted with piper cams (new).
Valve clearances set on bench. Put the head on the block today built the other bits up and on turning by spanner on bottom pulley there is a hissing from the inlet runners.
Have rechecked valve clearance no change.

I am no novice to engine building and my instinct tells me the valves can't be seated right.
Any other thoughts. I can't compression test as it's not fitted in a car yet.
Only other thought is a buying a boreascope see if it sheds any light.

Cylinder leakage test could be carried out without fitting the engine as could a vacuum test on the inlet ports. I have seen a vacuum tester that works off compressed air or you could use something like a multifaceted if you have access to one

New Cylinder leak tester compression leakage detector kit set petrol engine UK

you need one of these

Hi m8 what do you mean by inlet runners? What's an inlet runner?. Are you mistaking the hissing coming from the oil passages that go from the head to the sump area?

I put the throttle bodies on in an attempt to amplify the sound so if you like it's now the end of the trumpet. I put my compression tester on the engine and each cylinder is making aprox 50 psi which I know is low but I am only turning it with a spanner on the bottom pulley. Also I threw together a contraption to allow me to blow compressed air into the cylinder at tdc. Although there was some loss via the rings as I would expect I couldn't hear anything else so am tempted to just see what happens.

If the engine is out, fit the starter motor, apply 12v and you should achieve enough cranking power to get a good test. This is how I have done it in the past.

The hissing sound is just the inlet valve opening slowly from closed as you hand crank it and the piston pulls a vacuum, speed this up and the valve would open quicker and it wouldn't have the same effect.

My 2.3 duratec was the same, and I'm sure you'd find that with all engines under a hand cranked condition

Thanks for that it kind of sets my mind at ease a little that someone else has noticed it. As previous I think I will let it go for now and see what happens.
Thanks for the help folks