It's been a little while since I've managed to get any work done on this, other jobs have taken priority unfortunately.
Made a start on changing the timing chain chain gears yesterday, in the hope it will help out with the lumpy running and as a maintenance job regardless.
I've been waiting on the bits from Craddocks for almost 3 weeks, they were still unable to supply the cam gear and chain so ended ordering them from Turners.
Anyway, water pump off at the same time as it was weeping from the tell tale.
Gear cover off, nothing looking too worn or tired. Changed over the ratchet, spring and elbow on the tensioner. New crank gear and chain.
I had to fit the old cam gear back on, the new one from Turner only had 1 keyway and meant I couldn't get decent tension on the chain. The original wasn't showing any obvious signs of wear so I don't mind too much.
The original tensioner wheel went back on too, the new one from Craddocks was covered in some sort of storage wax which, without a blowtorch to hand, was impossible to get off.
I'll replace the seal before the gear cover goes back on, then it's on with the new water pump and back on with the sump, hopefully curing the leak there too.