high pitched metallic sound, not pinking

[GPO_Van]

Hi all
I’m stumped, with nowhere to go, my Moggy is now on the road, had a few teething problems (brakes failing) but she starts easy, runs well BUT.
There is a terrible noise comes and goes that sounds from the front end, having read all the blogs about strange noises I came to the conclusion it must be pinking as it seems to only happen under load, though it sometimes starts as soon as I head up the road from my drive, or may not come on for a mile or 2.
It sounds like a very strong spring under pressure being released rapidly, a high pitched metallic sound comes and goes, stops when I take my foot of the accelerator, it seemed to fit the bill for the explanations of what pinking sounds like, though in my days of driving old bangers in the late 60’s and early 70’s I can’t recall ever hearing it.
As per the instructions on the blog I moved the Vernier clockwise, 11 clicks (=-1deg) then came home another 11 then another 11, no change, thought maybe advance and retard aren’t working, so turned the whole dizzy anti clockwise, still get the noise then turned a bit more, losing power, still the noise, tried again, now running like a tractor still the bloody noise.
So it’s not pinking, after 5 years of work I’m just fed up that I'm stuck for what to do next.
Thanks

[Monty-4]

Could something be worn out or starved of oil in the rocker assembly? Could it be running too lean (hot and more likely to "pink")?

[philthehill]

Have you checked the condition of the crankshaft pulley as the riveted type can come loose and make a dreadful sound.
It may look OK but those loose rivets can be deceptive.
Check also the dynamo pulley if one is fitted as the same thing can happen there.

[Monty-4]

Also bent fan blades!

[ManyMinors]

Remove the fan belt and drive it around the block to see if the noise has gone. That will eliminate a faulty bottom pulley, dynamo or water pump or fan, for a start .

[GPO_Van]

Hi, thanks for your replies.
First I checked the oil feed to the rockers (thanks Monty-4) as I had already thought it did not look as oily as I expected looking down the filler cap, but all was well, nearly all the cups at the top of the push rods were full to over flowing with oil, I think it looked less as after an engine rebuild the oil is as clean as when it was put in. The engine is running slightly rich.
My next test after replacing the rocker cover was to remove the fan belt and go for a drive, but instead I decided to record the noise, after 3 miles I came back, NO noise!.
So what to do, am glad I did not take the belt off first as I would have thought Falsely that I had isolated the problem, with the belt off how far do you recon I could drive without overheating the engine, 2 miles?
So ManyMinors and Philthehill I have a quandary, I think I'll take it on a run, get the noise on then drive as far as possible with the belt off, yet the intermittent noise not coming on is a problem.
Thanks all for the input, any more ideas gratefully received.

[philthehill]

What do the bearings feel like in the generator/alternator & water pump?
Closely examine the fan blades for radial cracking from the 1/4" mounting bolts.
Check the crankshaft pulley rivets if a three piece pulley is fitted.
Check the dynamo/alternator pulley for cracking/loose rivets if a two/three piece pulley is fitted
Check the fan belt for shredding/cracking.
Important - Do not run the engine with the fan belt removed for any length of time as coolant will not be pushed around the engine and you will damage the engine.

[Monty-4]

Another note - I had a rocker adjusting screw that was worn and would go out of adjustment after very few miles. A fun way to check is to stick a 0.010" feeler gauge into the valve gap while the engine is running (can be messy with rocker cover off). If the ticking noise goes away - you've found the culprit!

[GPO_Van]

Well the noise is happening less often as I use the car.
I am now running with another pulley, even though the one that was on looks ok, have taken the fan blades off (putting extra washers in to match the thickness of the blade and plate), then took the car for a run and the noise came on as loud and nasty as ever within the first minute of driving, came straight home to get the camera to record the noise.
Drove off again recording, 47 miles later (several separate drives) no noise.
Because of the erratic nature of the noise can't try the fan belt off as odds are the engine will overheat before the noise comes on.
I think I'm best to use the car as it is now and ignore the noise till something breaks, or drops off.

[philthehill]

Which pulley did you replace?

You do need to get to the bottom of this as leaving could cause more damage and more expense.

[kennatt]

is the engine steady fitted and in good condition and properly adjusted, if not could be letting engine move about too much causing the bracket to click and rattle.

[GPO_Van]

Hi All
Bottom crankshaft pulley Phil as you suggested.
Ken the engine mounts are good and the head steady has new rubbers and was tightened without pushing or pulling the engine out of line.
I did another 5 miles today, no noise.
Fan belt and alternator new, pulley feels fine.

You do need to get to the bottom of this as leaving could cause more damage and more expense.

I've reached the point that if something is damaged I'll just have to buy a new part, or engine etc. but at least I could drive it further without all this concern, what I have spent already is useless at the moment as I'm not getting the enjoyment without the nagging worry.
Not going to give up, I love this little Traveller, even if it means selling one of my bikes to fund repairs .
Thanks for all suggestions.
Reg

[kennatt]

have you had a good look at the manifold, ,cracking,gasket, tightness ,because any slight leak can create a hell of a noise,and as it heats up the gap closes and the noise stops ,worth just giving the nuts a good pinch up,if ok take it off and have a look at the gasket.

[GPO_Van]

have you had a good look at the manifold, ,cracking,gasket, tightness ,because any slight leak can create a hell of a noise,and as it heats up the gap closes and the noise stops ,worth just giving the nuts a good pinch up,if ok take it off and have a look at the gasket.

Engine is newly rebuilt, all gaskets new, will try all manifold nuts this morning.
The noise has come on as soon as I leave the gate or after several miles (or not at all)
It only happens under load, foot off accelerator and it stops till I reapply accelerator, then decides not to happen whatever I do.
With the present changes/ things done above to eliminate items, it made a noise straight after driving out of gate, I came back to get a camera that records sound, since carrying camera approx. 50 miles no noise. ( no its not a noise eradication camera)
Thanks
Reg

[kennatt]

is exhaust clear of the frame where it drops under the bulkhead.

[Chipper]

Does the front grille assembly vibrate/resonate with the engine idling? Mine does this at certain lower engine speeds and gets quite loud, to the point where I recently re-adjusted the idle speed to quieten things down a bit.

If so, maybe your engine mount rubbers need changing - some of the modern replacements are made of overly stiff rubber, which leads to odd harmonics being transmitted through the surrounding panels.

Another thing that seems to vibrate a fair bit is the bonnet release mechanism rod, as they are usually quite a loose fit where it goes into the front panel. Perhaps try packing it out with extra spring washers if it's very loose...

[GPO_Van]

Hi all
Sorry for delay, wife went in for a hip replacement op and I've been rather busy with domestics.
Have tested out all your comments to no avail, but the noise has not been happening over the past 50 odd miles.
A friend of mine took a recording of the noise last month and has cleaned it up so the noise is more audible, I can't seem to add it to this message as it has the wrong extension (Morris nasty noise.aac)
I tried to put it on YouTube so I could put the link in this message but that does not let me as its audio only.
Any ideas on how to get this file to you please.
She's driving really well regardless.
Reg