Any advice is appreciated. A friend of mine is working on my Volvo after the front seal for the cam popped out. It was pointed out that something else may have led to this and someone said to clean out the flame trap. My friend mentioned that he looked for it and couldnt find it and after looking on here it's apparent that the turbos don't have one. So the question remains, what else could lead to this condition? Or should we just replace that old seal and test it out?

In the process he is replacing the exhaust manifold which has a crack in it, the turbo spins fine with no play. Thanks.