Chopped Cam

[James Cornell 10]

I have just bought a 1.9 8v to rebuild as my lump is still losing oil and not running very well and I have noticed that the cam lobe has a chip in it.

 

Is this common? Also is this cam scrap?

[James Cornell 10]

Here is a close up

[RossD 43]

Hard to say - Any damage to a cam is bad, but that looks to be on the 'base circle' section, so you might get away with it. Do a dry build and make sure that the section of cam with the chip in does not actually act on the follower at any point. If it doesn't you may be ok.

 

However, if this were me, I'd scrap it and get another cam, its not as if they are rare (yet!)

Edited April 1, 2014 by RossD

[James Cornell 10]

I think I'm more concerned about how it happened and I just wondered if it was a common place for them to fracture.

 

I suppose if I am having it all put for a rebuild it will be wise to change it anyway...anyone got a cheap cam :-)

[ALEX 98 1 Cars]

It might have been dropped out of the engine or just a bad forging, whats the bucket look like? A superficial chip shouldn't affect the performance and wear should appernt by comparing lobes.

[James Cornell 10]

The cam is still on so I am not sure at the moment, I need to start stripping it down...

[jdt 6]

I used to work for a camshaft manufacturer as an engineer for many years. (they are cast not forged)

If the lobe just has a chip and there is no wear on the lobe or follower then I would not be concerned.

Your photo is not clear but it looks like the cam nose and there is a bit of wear on it in which case it should be changed.

If it is the base circle it does not matter at all as there is no load.

The followers start to hollow out as they wear because they are continually being rotated by the cam lobe (which is not on the centreline of the follower so makes it rotate) you need to put a straight edge across them.

Edited April 5, 2014 by jdt