Loud ping from rocker or valve?!

[Adammcf]

For the last few days I was ocasionally getting a loud ping from one of the rockers or valves.
I adjusted the valve clearances tonight and everything looks fine but it was a little hard to turn at one point which got me worried thinking one of the valves was touching a piston.
Now the valve clearances have been adjusted to loosen them a little its better and the idle is alot better but I can still hear the loud ping noise coming from a valve or rocker every 20 seconds or so.

Any ideas? It has been absolutely fine until now but I did a 400 mile trip to north wales and back a week ago which may have loosened something up.

[GDBN]

Hi mate.... just wanted to say (after a bottle of red) that having adjusted the valve clearances the engine is completely different ......
Like a new engine .......was strangling the engine before .....WOW

[Martinaston]

Take the spark plugs out and have another go at turning it by hand.

One of the valves may be getting stuck open
Are all the clips that hold the rockers in place OK?

[Adammcf]

Hi mate.... just wanted to say (after a bottle of red) that having adjusted the valve clearances the engine is completely different ......
Like a new engine .......was strangling the engine before .....WOW

Good to hear! Mine idles ten times better now since adjusting the clearances. I think I had them a little too tight before.

Take the spark plugs out and have another go at turning it by hand.

One of the valves may be getting stuck open
Are all the clips that hold the rockers in place OK?

I'll try that tomorrow night. Before adjusting them last night I turned it over with the plugs out and it was getting very tight at one point. I just hope the valve wasnt hitting the piston!
If there is a sticking valve is there any way of curing it?

[Demlotcrew]

Head bolt washer anyone?

A

[Martinaston]

If it's a valve the only way i can think of curing it is to take the head off again and re-seat it. But then if it's been struck then it would probably need replacing anyway.
Do you have a compresion tester?

Demlotcrew ???

[Adammcf]

You think one of the washers could have split or something?
They all looked fine last night. The noise definitely sounds like a valve or rocker.

[Martinaston]

I'm not sure what Demlotcrew is refering to but the reason i suspect it's a valve is because if one of them is turning by few degrees each time it opens when it reaches a certain point in it's rotation it get's stuck open.
It could be a piece of chaff in the guide or a poor quality valve stem

[Martinaston]

Do you have single or double valve spring's ?

[Adammcf]

If by double it means there are two springs per valve then thats what Ive got. A smaller spring inside the large one.
I really dont want to have to take the head off again!

[Adammcf]

Any ideas folks?