Lancia Motor Club

Anyone any ideas on a high pitched buzzing noise in my car, it only seems to come on under load,not when idling, almost no noise when revving at rest although just detectable.
It happens in or out of gear , clutch in or out. I have tried to listen , but mainly only happens when travelling which of couse makes it really tricky to isolate . I am convinced it might be the coil, which seems unlikely , bizarre ! But it does sound like  an electrical noise rather than mechanical, I also thought it might be the distributor...

Possibly tappet noise? A loose or broken tappet adjuster might cause that sort of noise.
The usual noise culprits are the fan belt (more of a screaming/whistling noise if it's loose and slips) or generator (more of a rumbling/whining noise from worn bearings). The water pump bearings can get noisy too.

To locate engine-associated noise it's well worth getting a stethoscope like this: https://www.ebay.co.uk/itm/324630412995 (https://www.ebay.co.uk/itm/324630412995)
I've found mine really useful.

The differential? When was the last time its oil was changed? Andrea

Thanks for the replies. pretty sure none of the above,although possible I guess.I have tried listening at rest with a length of garden hose ! but as it is only faint at rest , even if revving , difficult to locate.Almost need a microphone placed inside the engine compartment !
Difficult to describe the noise but it really is incredibly high pitched, bit like a plague of locusts, or something out of Star Trek ! lol.
It will often disappear while on the motorway after a few minutes , only to return when slowed down.
It goes so well otherwise !
Oh well, not the end of the world , but very irritating all the same.! I have splashed out on a new coil, arriving soon , but knowing my luck , money wasted ! The one fitted is a Lucas one , possibly not correct, I dunno.
The car starts immediately so can't be much wrong tbf....
Oh yes , different thing , I reckon it might be running slightly rich, I have the handbook , but unsure exact adjustment screw to adjust .
Thanks to all !

My Appia developed a clicking noise which was coming from a dodgy rocker cover gasket. 

dry speedo cable??

Speedo cable was near the top of the list of possibilities, but still does it at rest, so, not sure.
Just remembered what the sound reminds me of , the dial up internet noise !
I might pluck up courage and fit the new correct coil, (I am not terribly confident mechanically), so fingers crossed, bet it isn't that knowing my luck ! But good spare part to own nonetheless I guess.

Well , much as I was delighted to have changed the coil myself, surprise ! The noise still persists... D'oh !

Now I will readily admit, my knowledge of Apia’s is pretty much zero.  However, some faults can be fairly common.  As far as I’m aware the Appia runs an inline gearbox.  So the front of the input shaft sits in a spigot bush in the back of the flywheel.  These will wear with age and may make a variety of noises, different loads, speeds etc.

Just a suggestion, probably way off the mark!

Cheers,  Peter

Yep , well , could be , I have thought about the various gearbox and clutch bearings too , if it is , might mean a tricky fix !