A few weeks ago I went for a short run , but soon was aware something was very wrong with the engine.
One cylinder was misfiring, loosing power and making a bell like clank in time with the engine.
"Oh No" I thought, this sounds expensive as I nursed it gently home, luckily only a couple of miles.
Very close to home tickover went and turning into my street the engine finally gave out completely, but in a graceful way not locking up.
Long story short, the key which secures one of the timing pulleys to the end of the cam had eaten into the pulley itself, gradually making the keyway bigger until it met itself and was barely driving the cam round, if at all, picture below. The end of the cam with the keyway was also damaged.
Thinking it could have done untold internal damage to the valve train, I quickly decided it was a job for my dealer.
I think it says a lot for the robustness of these engines that after a deep investigation only a new pulley, cam and drive belt were needed. Additionally a new valve and collar were reccomended and fitted, as they must have taken some punishment as the pulley expired.
I have just received the car back a month later, most of the time with the dealer being spent aquiring parts.
Plaudits to Oakmere Morgan for a quick diagnosis and fix once the parts were available.
So my message is , keep an eye on the timing pulleys, looking for any wear around the keyway - there should be none.
I have no idea how long this took to fail, or even why in the first place it did, which is worrying !
In the picture below the one on the right is OK , the left one is the clearly the damaged one.
It looks like the wear has started at the front ( making it more visible than if it started at the back) as there is the remains of the keyway existing at the back - but this is conjecture.