I have a question that has been bothering me. When I took the head off to have it refurbished I backed off all the bolts on the rockers so there was no pressure on the cam shaft. Still, in order to get it out I had to hit it from the end with a nylon rod and a hammer. It did not slide out easily. Is it supposed to just slide out?
Yes.
Now that I am reassembling it I again had to hit it with a hammer (wooden) to get it back in. It does not turn easily. There is a rather large amount of friction to overcome, but then it turns fairly easy for a bit before sticking again. It has been lubricated, so oil is present in all bearings. How easy is it supposed to turn?
You have something wrong Jon. Either the head is warped or the camshaft is bent. Since it was like this before you stripped and had the repair, if it is warped, it was warped before the repair.
The camshaft should slide in and out easily and you should be able to spin it by hand.
I was surprised when I noticed that there is no bearing inserts for the cam shaft to turn in. Apparently it just turns in the aluminium that the head is made of.
Which is fine. Many engines are like that.
Can I just hone the bearing a little bit until the cam shaft slides in easy, or is it really supposed to be that tight a fit?
No. Don't do anything like that until both the head and cam have been measured for alignment. You need to know what is faulty. Imagine a bent cam - if you removed metal from the cam bores on the head you would have to take so much off to allow for the oscillation that the clearances would be too great and you would loose oil pressure.
If the head is warped, you could have the cam bearing holes line-bored but they have to be aligned with the head face otherwise as you torque the head down it will force them out of alignment again.
Years ago Dolomite Sprints had this problem where the heads were distorted and people skimmed them flat leaving the cam bearings out of alignment, and then they would snap the camshafts! So the head face and cam bearing holes must be accurately aligned. If you have to line bore the cam bearing holes then either they will have to be sleeved to bring them back to the original size to match the camshaft, or you would need cam bearings to take up the clearances.
Note the cam bearings are all different sizes.
Regarding the inside of the gearbox end casing, you do have to remove a little from the boss around the bolt holes otherwise the teeth of the larger gear will foul them. You can check this easily as you offer the casing up to the new high fifth installation.
Roy
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