New camshafts needed?

[JerryL770]

My E went into the Splined Hub the other day for some general service work and tune up. I asked for valve clearances to be checked because I thought it sounded a bit noisy.

I was told I need new cams as the wear on the lobes was going through the hard layer as witnessed by the stripes in the nose of this cam:

Others tell me that terminal wear is virtually unheard of for XK camshafts. If the speedo is original, which I think it is then (although rebuilt) this engine has done ~91,000 miles.

The cam will be extracted next week for careful measuring to try to establish the actual amount of wear. There's no problem with oil supply to the rocker covers.

[JerryL770]

Well, we came to the conclusion that there is little to worry about. I spoke also with our local engine machine shop which has years of experience refurbushing XK engines including cylinder heads and they cannot recall a need to replace a cam which has not been abused by lack of oil. Excess wear will most likely show most easily by wear marking on the cam followers - none visible.

So all my valve clearances were checked and it was closed up. The carb tune has made tickover much better.