Strange noise from engine bay?

[stephenpolhill]

Hi there.
I noticed this one cold evening when starting the car, a cold scratchy sort of noise. I drove on and she ran beautifully but still making the noise when I got home as she was warm.
The next journey I didn't do anything and the car was fine and then it started again this morning as I started it up to go to work. No performance is affected, oil is fine, its just the noise.
I have uploaded a video here - http://www.youtube.com/watch?v=YsbO5BShrCM - the video doesn sound bad but thats the noise it makes over the usual engine noise.
I would appreciate it if anyone could listen and see what they think about it?
Cheers
Steve

[dalebrignall]

i was wondering if manifold gasket is going it seems to make a futt futt noise .

[stephenpolhill]

Inlet manifold or exhaust?
Remember we rebuilt the engine last year, would this still be an issue?

[chrisryder]

haven't listened to the video, no sound on this comp! if it's a pft pfting noise as another poster mentioned, it could be the exhaust joint clamp. if the exhaust joint or the manifold gasket (for the exhaust ports) is leaking then you may be able to see black traces of 'soot' or even see faint whisps of smoke in the engine bay with the engine running. you can also (carefully!) hover your hand around the exhaust clamp to feel for warm jets of air.

will try and listen to the vid later on another comp!

[stephenpolhill]

I will check that next time I start her up. Too cold to start just for a nois atm. It sounds noisier around the front right (carb side) of the engine block. It is a noise as if metal was rubbing against each other. Hmm

[beero]

Sounds like something to do with the fan belt / water pump / dynamo. Take the fan belt off, run it for a few seconds and see if the noise goes.

[chrisryder]

having heard that now i'm tempted to agree with the fan belt/water pump/dynamo idea.

i had a similar odd noise coming from my minor a while back and took the fan belt off to see if that eliminated anything. ran it without the belt and it still made the noise. dismayed that it must be something more serious i refitted the fan belt and heard the noise! i thought 'this is weird, the engine isn't running!'

turned out to be the front pulley on the end of the crankshaft. it was the rivetted type and the rivets had started to pull though (rotationally) so the pulley was loose on the central hub to which it is rivetted. could be that, i'd take the fan belt off if i was you and run the engine, as suggested, briefly to see if that stops the noise. and check that bottom pulley while you're down there!

[mrmorrisminor]

Could be dynamo related, if my memory serves correct there is a lubrication point at the back for the bearings. The cold could have thickened any lubricant in there making it less effective? A long shot but a quick fix

[Dryad]

Sounds like dry bearings in either the dynamo or water pump. As mentioned here already, removing the fan belt and seeing if the noise is still there is the way to find out. Having said that, mine has started making a similar sound in the last couple of days, but I think it's the bearing on the input shaft of the gearbox.

[stephenpolhill]

Thanks guys. Back from Holiday now so can between work try and fix it. I had a look at the dynamo but where and how do I lubricate it. Couldn't find it in the book ??

[simmitc]

The early dynamos had felt pads that could be lubricated. Later ones have a small hole in the very centre of the read end (where it sticks out) but I've also seen them with "sealed for life" bearings and no hole. BTW, the carb is on the left hand side of the engine, always make reference to sides as if one is sitting in the car facing forwards.

[stephenpolhill]

Ok will take a look. Thanks.
I guess that shows whether the person is strictly a driver or actually works on their car

[bmcecosse]

Is there no noise if you run it with the fan belt off ?

[stephenpolhill]

I haven't tried it yet however my boss who did his apprenticeship on mogs and worked on them for sometime listened to it himself and reckons it was the belt and fan pulley and just needs a spray of oil while running in there. I'll go try

[MarkyB]

I think he was pulling your leg, the fan belt relies on friction to work.
Lubricating it is a terrible idea.
Did he get passed the making tea stage of his apprenticeship?

[stephenpolhill]

Well. Had it running and sprayed some duck oil onto where the fan and belt meet and the noise disappeared. Saved me taking anything off!
Thanks for the advice though, if I had the time I would've taken it off and found that anyway. Quick responses as usual
Cheers

[stephenpolhill]

Mark - I did wonder this but it has solved the problem which is a bit strange.
Can you think of any reason why it would have been this?

[bmcecosse]

The belt must be knackered - it will now be liable to slip with the oil on it! New belt asap.