Post Mortem needed for a Mr. Cam Sprocket please!

[470four]

Had this fitted to a 400/4 camshaft I bought off ebay some weeks back - the cam is fine, the sprocket is a little worse for wear...



Needless to say the chain has been jumping the teeth to a large extent! On say a rear drivechain sprocket this is easily do-able by the mechanically unsympathetic - surely on a cam sprocket it would only jump a few before mechanical carnage ensued between pistons & valves, stopping the engine?

My only guess is that the owner had run a presumably very noisy loose camchain for quite a while, running the sprocket teeth into needlepoints before it finally slipped round, taking the tops off?

Your thoughts:   

[mick]

I think he got his money worth out of that   

[Bryanj]

VERY worn and neglected chain and yes the valves should have hit the pistons---have you removed them and spun them in the guides to check?

[Spitfire]

That is very nasty, must have sounded terrible.

Cheers

Den

[470four]

VERY worn and neglected chain and yes the valves should have hit the pistons---have you removed them and spun them in the guides to check?

Not my engine, only bought the cam/sprocket so I dont know! 

I would have thought it wasnt a pretty sight... aircooled engines are never quiet but FFS - why run it into this state??! 

[Bryanj]

When I was younger (and no dinosaurs did not rule the planet then!) for my sins i ran an Enfield Crusader sports and the gearbox sprocket came out looking like that but in my defence i was only on