Clickety-Click annoying noise.

[CheeserBeezer]

Hi. As you are all aware I am well on the way to getting the 'Manchester Ship Canal RGS' back on the road. Upon installing the engine and just turning it over with no plugs in there is a distinct, loud,  'click' which sounds like one of the valves closing noisily against the cylinder head. Obviously the head has been reworked by myself, fitted with original Terrys springs. I have always found alloy heads to be noisier than iron heads. I'm hoping this isn't going to rattle badly on startup. I've heard some very noisy alloy top ends and i've heard some quiet ones. I suspect that the noise is caused by the cam follower dropping off the cam very quickly (357 cam) which transferring to the valve hitting the seat very quickly. Any experiences out there.....?

[RDfella]

Or backlash in the gears - seem to recall someone recently had a similar issue and it was the cam gear not tight, which allowed the cam to momentarily accelerate under spring pressure.

[CheeserBeezer]

Thanks for that. This noise is definitely coming from the cylinder head. When watching the rockers go up and down the click sounds like the impact of a valve closing against the head. One seems to be much noisier than the other three which can hardly be heard at all. I'm wondering if the camshaft has one lobe which is slightly misformed, allowing the cam follower to fall away very quickly.

[Klaus]

I had a similar hard knocking after the ignitiontiming failed, befor the engine runs very smooth. After resetting the ignition this clonky noise appeared at every turn. Scrach my head, and dismanteled the engine. Put off the rockerbox and turn the engine no clank. The clank come when the pushrods are under pressure. I have checked all, cams were billiant, followers looks like new. The clank were only when the outletvavle begin to open, does not matter which cylinder. It drive me cracy, when I happened to see the camshaft sprocket kicking back a little while turning. The nut was properly secured but the gear was not really tight. The gear wheel moved very slightly on the camshaft key. After properly tightening the screw, the clonk was gone. So have a close look at your camshaft gear.

cheers Klaus

[CheeserBeezer]

Thanks for that. I'm pretty sure the gear is tight and, as yet, the pinion is not connected to the magneto.