I've just had a small block 360 rebuilt. It now has a terrible tick on the driver's side. It has a hydraulic cam and lifters. The oil pressure on startup is 40 lbs at idle and when the engine's warm pressure drops to about 10 - 12 lbs at idle. The motor has about 45 minutes drive time on the rebuild and at one point the noise went away for 20 minutes or so. Runs good and stout with no missing or backfires etc, just a loud and annoying tick under the driver's side valve cover. I have changed the rocker arms and shafts. (shaft holes pointing down toward the outside of the motor). The oil is a straight 30W. Do I need to go to a higher weight oil? It's driving me nuts! does anyone have any ideas?
