Sounds like a typical stuck lifter--how long have you run it with it
Clicking?

Have you tried to adjust the rocker's?

If it's a pounding, or Banging----rather than a tick or a  click---I'd
say Ooops--- it's rod---

Hard to diagnose without hearing it, but if it happened all of a sudden,
after you parked it, it sounds to me like a blend down lifter----

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Terry--

       "Zoom, Zoom, Zoom"
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http://community.webtv.net/CTONLINE/TerrysHighOnLife