Cam bolt stuck in cam caps...?

[ctnewman]

When i removed my cams from my GTR the other day, a few of the bolts were stuck in the caps, I am sure i could get them out if I backed them out with a wrench... but what would cause this? I unbolted the cams carefully, gradually and in sequence... Should I be worried?

[proengines]

It's a pretty common problem, I had one last week the same. The bolts are a very snug fit in the caps as they work as a locating dowel to locate the cap properly on the head to ensure the caps align in exactly the same spot as when the tunnels were bored.

You can usually get them out pretty easily if you warm the cap up and spray some good penetrant around the bolt and leave it for an hour or so to work its way in. If you then use a spanner to work the bolt back and forwards it will usually loosen up and come out. I did have one that wouldn't and had to hold the cap in a vice (use soft jaws!) and tap it through with a pin punch, you may need to replace the bolt though if you damage the thread. Go slowly and carefuly and you should be fine, once the bolt starts to move it will pop out easily. I soda blast the inside of the bolt holes to remove any gunge and buff the bolt clean and use some nulon when I reassemble them and it works fine.