Re: Camshaft Bearing Question
How did you find out that it's a camshaft bearing?
There are 4 of them, and they rarely cause any trouble, but they will wear as any bearing will, excessive wear on just one bearing usually will not happen, as the other bearings will take up the slack, unless some debris got onto the bearing surface.
It is possible that one is spinning and making a noise, however I have never seen this myself as they are usually seated very well due to being pressed in.
To change them the cam has to be removed, this is done by removing the water pump, everything fitted to the crankshaft, and the timing cover, then unbolting three bolts at the top timing gear, removing the top timing gear and chain, then removing the cam holder plate, wich has two hex bolts and pulling the cam out. The pushrods and lifters must be removed prior to pulling out the cam.
A special tool is used to knock them out, this can only be done with the cam plug removed, wich is located behind the flywheel cover, so the engine must be separated from the flywheel cover, and most likely the flywheel has to be removed to make enough room at the back of the engine to get the tool in to knock out the bearing closest to the front of the engine.
It is possible to get the bearings out without removing the oil pan, but drop one down there and the pan will have to come off. In other words it's easier, and most likely necessary to lift out the engine before removing the bearings.
On the other hand it's much more likely that your problem is something else interely.
Try checking for timing chain stretch, bad lifters or pushrods, broken or worn valves or other valvetrain parts.
To check the cam you can remove the top timing gear and the lifters (making sure you put all the lifters and pushrods back exactly where they came from) and spin the camshaft by hand feeling for rough spots and play, a little in and out play is normal but there should not be any play sideways nor any rough spots or noises.
