QUOTE(larss @ Sep 24 2011, 09:49 AM)
Took the cam sout of my spare engine and found this type of groove at top of both of the two middle lobes (not at the outer ones).The engine has some 150.000 km on it. The lifters looks wery fine.
Is this from wear or what ?
Should I dump this cam?
/Lars S
That is excessive wear. See that recession in the middle of the lobe? The pressures on the lob concentrate in a point just below the lobe surface. That effect causes the lobe surface to collapse without any external signs of wear.
Newer cams have a black coating that helps lubrication.
I'm sure the lifters are done as well. Take 2 lifters, clean them and put them face to face and look against a light source. Their surface is round so they should touch like this )( and you should be able to see light between them. If they are worn out the surfaces will be || or worst () so you will see full contact between the surfaces.