Tick coming from the passenger valve cover

[sirfunkeybut]

It will tick around 10 times, pause, and repeat. Is sounds like an electric arc. I removed the oil fill cap and that's where it's coming from. Is there anyway to tell if it's the lifters, pushrods, or rocker arms? It's a 90 bronco II with a 92 explorer 4.0. Thanks for any help.

 

[PetesPonies]

Did you grab any rockers and see if they move> Wear marks would be next to look for once you know which one it is.