I have a pile of camshaft bearings that I am going through and I fear they are all front bearings, both for the pre-24 and for the later camshaft. Their lengths match what is in the MTFCA engine rebuild manual. But the center camshaft journal is considerably longer and it is barely even mentioned in the booklet, nor is the direction the notch goes indicated. I can't seem to find any measurement for the length of the center bearing halves from edge to edge. I assume it almost touches each lobe on either side, like the front bearing? If not, perhaps some of the ones in my pile might be for the center bearing. Photos would be helpful to see a side-by-side comparison.
And what is the standard diameter of the bearing area on the camshaft so that I can measure wear? I can never seem to find spec's when I need them. And when I don't need them, I seemingly come across them in my reading every other page!
Thanks in advance.
The centre cam bearing looks totally different. It is tapered on both ends on the outside
Les you just beat me with that!
"The centre cam bearing looks totally different. It is tapered on both ends on the outside"
I was afraid of that! None of mine in the pile are tapered on both ends. And what is the length, please? Does the center bearing almost touch either cam lobe? I would assume so to maintain camshaft thrust movement.
Marshall- the center cam bearing does nothing to control end thrust of the cam. If you do find some center bearings, the notch should be on the top side of the bearing when the anchor bolt hole is positioned to the outside of the engine. Actually you can use either style of the front bearing in the center position if you don't have a center bearing. The thrust is controlled only by the front bearing. Use caution when using the early bearing on a reground cam as the heel of the cam lobe can slip into the notch in the end of the bearing.
Thank you Dan, Mark and Les for the information. This is most helpful. I think I may be able to piece together enough good bearing halves with sufficient Babbitt to get a nice fitting camshaft. 'May have to cheat a little on the center cam bearing and use a front one, preferably the longer version. I wonder why Ford made the center bearing so different without any true end thrust control between the two cam lobes at either end? That would have taken the load off the front bearing.
Thanks again for your input. Maybe it will also help others in a similar situation.
There is another problem... You can only use cam bearing halves that have been together all their life! Cam bearings came from the factory in one piece and were cracked open with a cold chisel, then reamed. The two halves are basically two pieces of broken cast iron and because the breaks are random, the only two halves that will properly fit together are the same two halves that were originally broken apart 90 some years ago!