Light tapping from engine

[Dutchone]

When low speed cruising I can hear a very light ticking / tapping noise from the engine. (cannot hear it above the exhaust note when accelerating )
No it's not a bird asking to get out of the engine bay - I have checked!)

It reminds me of one slightly poorly adjusted tappet in the days before hydraulic tappets. I think it changes with revs, but hard to say as I can only hear it at around 1500/ 2500 rpm
I don't think it is anything serious (hope), but once it seeps into your mind it wont go away and spoils the smooth hum from the engine.

Any ideas please, because I would like to sort it if possible.

Thanks, Paul

[deeen]

My first guess would be pinhole in exhaust manifold, or in 4into1 weld on exhaust manifold (yes mine has had all of the above!)

[crankedup]

Agree, it could well be the manifold leaking slightly.

[IPAddis]

It could also be the cam starting to wear. They last between 30,000 miles and 80,000 miles generally.

Ian A.

[DustyC]

crankedup said:

Agree, it could well be the manifold leaking slightly.

Or just the mainfold gasket needs replacing.

[Dutchone]

Oh!
I have just had new head gaskets fitted by a garage, and they have obviously had to take the manifolds off to do the work.
But I did not associate the noise with the exhaust system until your replies have all pointed in that direction.
Trip back to the garage then.

Thanks, Paul