Hello everyone, this my first post though I've been a long time reader of this site. Just wondering if anyone has ideas on this.

Important stuff to know: Car is 94 EF 6 cylinder, 5speed manual (standard and not converted from auto). Completely stock except for extractors.

Had a slight overheating issue (!) in which the engine seized up, warped my head and blew the head gasket. Filled the sump with lovely green coolant too. Anyway took the head off, sent it away to get reconditioned and put it all back together. Car starts and idles fine but has a loud ticking (quiet loud) whenever the engine is under load.

Work done to the head consisted of straightening the head, replacing all valve seats and getting a shave. I also whacked on an AU head gasket.

Car seems to be making good power, revs cleanly except for the very loud ticking noise. I first thought sticky lifter (i know they're lash adjusters) but only happens under load. best way to describe the sound is a very loud sticking lifter noise.

Could this be a timing issue, maybe the timing chain has slipped a tooth on the aux shaft or crank shaft, i was jiggling it around a bit when rotating the engine whilst the head was off. I had the chain zipped tied to the cam sprocket so it didn't move. The mark on the cam sprocket sits in the correct spot (just above the top of the head) when at TDC.

What about compression, is it possible that with a thinner gasket and decent amount of metal shaved from the head that I now have too high a compression ration for normal fuel? It's running on standard unleaded the moment.

There are no mods done to the engine except for extractors which have been there for 6 or 7 years.

Just after some ideas. When I was taking the rocker gear off some of the HLA's fell out but i stuck em back in (making sure they went in the right way)..

Wade

did you re-shim the rocker gear and HLA's when you rebuild ithe rear (if you rebuilt the gear that is) if the HLA's fell out maybe the shims also dropped.. that would cause it to clack like hell.

Didn't notice any shims falling out, then again theres a bit i didn't notice till much later.

And i didn't pull the rocker gear apart, i took it off as one piece. I'll be having another look tonight so i'll repost tomorrow and let know how i get on.

Wade

Try tightening your extractor bolts on the head. I just nipped mine up when i put them on and did exactly what your describing. Really wrench on them, tight (don't strip them though, its ally)

Exhaust manifold leaks do sound as described, Moody's suggestion will at least eliminate any doubt.
Paul