(G) uno whistling... very strange

for some reason, my 88 uno 45 whistles. sometimes its a really high pitched whistle that sounds like somethings gonna burst. and sometimes its a less high pitch whistle. sometimes it does it through 1st and 2nd gear, and sometimes it whistles through to 3rd and a little bit in 4th. Somtimes it whistles while idoling, sometimes it doesnt.

strangly, it does not effect the performance at all. anyone have any ideas as to what it is? if not... i can survive with people giving me strange looks.

i can just tell them that its the turbo...

Hi Yeah-nah,

I can think of three likely possibilities - an air leak at the inlet manifold or carburettor mounting, or a squeaky V-belt (possibly alternator itself), or the cambelt tensioner pulley if particularly dry of grease...

On the FIRE, the V-belt only drives the alternator, so it's quite safe to remove the belt and go for a drive to see if that's the culprit. An average battery in good condition should be able to run the engine for at least an hour, probably two, but it will be less if the headlights, wipers etc. are on.

As for the inlet air leak, it's a case of checking that the manifold nuts to the cylinder head are tight, and also the two bolts that go right through the carburettor (you see these bolts when the air cleaner housing is off).

The cambelt tensioner is best checked by carefully removing the belt (turn the engine until lined up with TDC first), and spin the pulley with your fingers. Should be smooth and quiet - ideally quite 'sticky' with grease - but at least not 'dry' and rattly.

Cheers,
-Alex

I agree with Alex. If it does it when revving the engine occasionally then it could well be the alternator belt. If it is intermittant, I'd suggest that cambelt tensioner bearing is on the way out.

Do what Alex suggested and you should be able to isolate the problem

What are the origins of the whistling sound - engine, undercarriage, brakes .
I would guess cambelt tensioner pulley. It is very noisy/squealing when nearing its end. When I shot one, I found a handful of its balls in the bottom of the plastic cambelt cover. I thought it had been the alternator belt and never paid enough attention to the noise .
Tough engines, are not they, to survive a cambelt failure?

Two other options:

Clutch bearing could be making a noise - problem with this bearing is its always turning so its hard to test.

The other is the ignition coil! We had an ignition coil that made an incredible noise.

Clutch bearing failure is normally easy to detect. It tends to rattle at idle, and screech when engaging the clutch. In my experience clutch bearing is noise is normally constant, so if it's intermittant I'd go for alternator belt/ alternator bearing or cam tensioner bearing.

And you had an ignition coil that made an incredible noise?!!!!!!! What did it sound like?

Yeah, the coil was probably more of a screaming noise than a whistle just every now and then

you sure it doesnt just want to be a Turbo for a short while?! haha

Yes I remember that squealing ignition coil that jjhepburn mentioned...
It was a really weird series of problems - first the engine idle speed would mysteriously switch between two speeds (timing light showed that ignition advance was switching between two settings!), then the engine was always over-advanced when hot so it sounded like a flat battery when trying to start (we never really did solve that problem).

Finally, that ridiculous squealing noise (LOUD, like a slipping belt) - it would do it when turning the ignition key on, before even starting the engine, and the rev counter needle would kick around...

We couldn't decide whether it was the coil or the electronic finned module... I fitted a contact-points distributor (off a 128) and the engine started and ran fine... then smoke poured out of the ignition coil and the engine stopped. The moral of that story was that you can't use an 'electronic'-type coil with a points distributor. And also, the squealing coil was finally dead...

-Alex

On my brothers uno while he was driving he got a whisling noise, found it to be one of the cv boots and just sprayed it with lube spray and it was sorted.

i'm yeah-nah's friend, this is like a revving whistle, so as the revs get higher the whistle gets louder, i'm pretty sure its the belts, will get him to come around to mine and we'll look at it.