Need help identifying an ?engine? noise..

[stouchton]

Folks - need to help isolating a possible engine noise.

Sounds like tapping a piece of sheet metal with a hammer (gently). It is intermittent, kind of comes and goes.

Sounds like it is coming from front of engine, loudest when you listen directly in front of radiator.

I removed fan belt and it stopped.

Water pump seems fine, fan is tight and there is no side play in end bearing. In/out play is about .010". Bearings feel fine.

Generator does not have any play, though the rear bearing has a squeak and it cannot be lubricated externally - heard it using a stethoscope.

Crank pulley is tight and runs true.

In fact all pulleys run true.

Only suspicious thing I noticed is that I needed to slightly lift motor to slip v belt back over crank pulley - guess my front mount springs have sagged slightly.

After putting the v belt back on the sound went away for a while (couple minutes), then reappeared.

Can not isolate it with stethoscope - but definitely sounds like tapping on sheet metal with hammer. Not continuous tapping, but an intermittent tapping: tap tap pause pause pause tap pause pause tap tap tap pause pause pause pause tap ......

Anyone have any clues??

Thanks,

Scott