Clattering noise

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oliver90owner
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Re: Clattering noise

Postby oliver90owner » Tue Nov 05, 2019 10:34 pm

... it only has to stall and you risk sucking water back up into the engine....

I cannot see how! The Moggie has virtually 7” of ground clearance and the tailpipe is not the lowest point.

Secondly, unless the engine were to ‘run backwards’, there would be exhaust gases filling the exhaust. Only when the water is above the manifold level would water get into the cylinders. More likely, by then, that water would get in the bottom of the engine via somewhere else!

geoberni
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Re: Clattering noise

Postby geoberni » Wed Nov 06, 2019 9:56 am

oliver90owner wrote:
Tue Nov 05, 2019 10:34 pm
... it only has to stall and you risk sucking water back up into the engine....

I cannot see how! The Moggie has virtually 7” of ground clearance and the tailpipe is not the lowest point.

Secondly, unless the engine were to ‘run backwards’, there would be exhaust gases filling the exhaust. Only when the water is above the manifold level would water get into the cylinders. More likely, by then, that water would get in the bottom of the engine via somewhere else!
OK, I may have overstated by saying 'engine'; if it stalls and the exhaust is under water the gas in the exhaust will rapidly cool in seconds and pull into the exhaust, the thermal shock can easily damage the silencer (and the Cat on a modern car).
But my main point is that driving through flood water covers all manner of hazards, whether a Minor or a modern.
Basil the 1955 series II

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kennatt
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Re: Clattering noise

Postby kennatt » Wed Nov 06, 2019 10:59 am

have you checked that the pressure of the water hasn't simply pushed the exhaust down pipe to one side and its now close to the chassis ,and hitting it on acceleration .

oliver90owner
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Re: Clattering noise

Postby oliver90owner » Wed Nov 06, 2019 11:53 am

Ken,

My initial thought - but dispelled by the OP after he gave us the actual details.

Water hardly deep enough to wet the bottom of the diff casing, going slowly. Sufficient water ‘pressure’ to displace the exhaust system appears to be absent. Not deep enough for the prop shaft to stir up any water - and not turning that quickly.

So was engine damage (unless the only service item he does not mention was missing and the entry speed was somewhat higher than reported).

The popping on over-run, since, would possibly indicate a misfire or perhaps an over-enriched mixture (so an air filter in situ?).

‘Clattering’ certainly seems to indicate metallic contact. My best guess is still engine mounts... but only a guess...

Owlsman
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Re: Clattering noise

Postby Owlsman » Sun Nov 24, 2019 11:10 pm

Did we ever get to the bottom of this? Or even the top of it......if the noise was coming from above one of the pistons!

oliver90owner
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Re: Clattering noise

Postby oliver90owner » Mon Nov 25, 2019 12:08 am

We haven’t, but the OP may have. They have not been signed in to the forum since the 8th.

Owlsman
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Re: Clattering noise

Postby Owlsman » Mon Nov 25, 2019 3:22 pm

Yes, as someone has posted on another thread, it's handy if OPs do give an outcome to whatever issue they raised as it may help others in the future with a similar query/problem.

myoldjalopy
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Re: Clattering noise

Postby myoldjalopy » Mon Nov 25, 2019 10:47 pm

Owlsman wrote:
Mon Nov 25, 2019 3:22 pm
Yes, as someone has posted on another thread, it's handy if OPs do give an outcome to whatever issue they raised as it may help others in the future with a similar query/problem.
Quite so - and it is rather inconsiderate to those who have tried to assist as well :(
This is not the first time people have requested that posters conclude their threads with the outcome........


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