ok so I fit my head to the engine, timed it up nicely as it's easy, started it up n cyl#1 wasn't firing at all.

Did compression test n zero comp on that cylinder leading to me suspecting a stuck open valve.

Took head off and found that both the #1 inlet and exhaust valves were bent

So, this made sense as the head is off a fiesta rst which had chucked a rod through the block. Yup I did notice when I cleaned the head that a valve was open but assumed it was just the cam position it was taken off in.

Now my old engine was also a 1.6cvh but an old carb jobbie. I inspected the valves and measured them and found them to be the same diameter as the rst head.

One spring compressor fun time later and i'd put them in.
Head back on, inlet, exhaust, plumbing and wiring reconnected. Topped up with water and fired her up again......

Started up fine 1st time so i let it idle without touching the accelerator till it had warmed up a bit.

Weeeeeellll revved it up to about 2k really gently and it starts making a nasty clattering sound. Sticking my ear to a block off wood on the rocker cover tells me it's coming from cyl#1....

The question is have I made a bit of a mistake by fitting an inlet valve that isn't quite the same as the rst one?

It's the same diameter and obviously length etc but isn't as dished out as the turbo one.

Here's the pic of my old cvh head:


As you can see this pic of the rst's inlet valve shows how dished they are:


Now is it this machined away for the purpose of piston clearance or just compression or something??

I'm a bit lost and yeah I know I should have waited to buy another proper one but is was saturday and Ford quoted me £29 for 1 so I thought i'd chuck this one in and give it a whirl.....

Please help if you can as i've put this engine together twice now and ain't gonna test those head bolts a third time