Diagnosing engine ticking...

[Ben]

My engine has developed a ticking sound over the last couple of weeks. Loudest when cold but still audible once warmed up.
The frequency rises along with engine speed, even when in neutral (so can't be driveshafts etc, must be engine).
Also, I have a pipe going into a bottle from the rocker acting as an oil breather/catch tank. I have noticed a lot of fumes are coming from here, and I don't think they used to, so I think the pressure in the head may be higher than normal.

My first thoughts were that its most likely to be conrod bearings, as the heads only done 10k since a rebuild, but I'm not sure its loud enough to be conrod bearings, and it doesn't seem too shakey to drive etc.

Anything sound familiar to anyone?

[pugmanxud]

Colud well be an injector. put a biggish screwdriver on it, blade on the injector and andle to your ear. also try cracking the pipe off whilst idling and see if it goes on each injector

[jammapic]

Use the handle for your jack... put it on different parts of the engine, head, block, pump etc and the other end on your ear... you should hear it.

[Ben]

I used the above method all over the engine and did hear different noises in different areas, but nothing decisive.

My neighbour suggested that it could be camshaft or little end bearings and advised an oil change to see if it quitened down. I've changed the oil but no change yet.

Next I will try changing the injectors and then I'll go from there.

[Jenkosowls]

Last time I heard this sound the engine later exploded not long after. Could never find where it was coming from