Ha.
And that's the difference Patrick!
It was a tinkeling sound rather than a clicking sound!
If you'd kept driving, like Wally gates did, or like Steve Byers did,
or i did with a Sprite (many years ago), you would have just had a
shrapnel dented cylinder head roof and piston!!
Here is the problem......
The top ring wears through the alloy piston, and the ring gap is worn
and increased. The ring "flutters" in the worn ring groove. The ring
breaks, and starts to erode the ring lands above and below, due to
increased tolerances. The ring land above and below it is then eroded
to the point of failure. The alloy ring land is no match for the
fluttering steel ring.
Then a chunk of the top (crown) alloy ring land parts company from the
piston crown.
Followed by the broken piece of steel ring.
Then the clinking starts. The piece of steel ring bouncing around in
the combustion chamber.
Until it exits via the exhaust valve with an obvious clinking. And you
hear it all the way down the exhaust system!.
You just didn't drive it long enough for the clinking!!!!
What does the top of your combustion chamber/ piston look like???
Like its been Shot blasted with a square section piston ring??
At least you know what the noise was Patrick. I still think the other
issues will be cam followers/ cam and little ends.
This issue seems to occur only on cars fitted with new rings fitted to
old pistons, when the pistons probably should have been replaced,
rather than re ringing.
Best
Chris
Sent from my iPhone
On 29/05/2011, at 9:12 PM, "Patrick and Caroline Quinn" <p_cquinn@tpg.com.au
> wrote:
> G'day
>
> Listers would recall the loud and expensive noises coming from the
> engine of
> the BN3/1.
>
> The engine is still in the car, but everything hanging off it has
> now been
> removed. Yesterday my eldest son and I removed the cylinder head. It
> was a
> struggle, but once the overdrive throttle switch was removed it was
> possible
> to lift the head, move it sideways and then away from the engine.
>
> At first glance everything appeared as it should be, but looking more
> closely today, a 12mm by 5mm piece from the edge of the crown of the
> No 2
> piston was missing. Small bits of aluminium were embedded in the top
> of the
> piston and minor damage was evident in the combustion chamber. The top
> compression ring was intact hence the smooth but noisy running.
>
> Watch this space.
>
> Hoo Roo
>
> Patrick Quinn
> Sydney, Australia
>
> On 4/23/11, Patrick and Caroline Quinn <p_cquinn@tpg.com.au> wrote:
>> G'day
>>
>>
>> Here is something to get your collective minds around.
>>
>>
>> Yesterday morning we were 560 kilometres from home in the BN3
>> having just
>> crossed some many kilometres of featureless plains and semi
>> dessert. We
>> arrive in a large town looking for fuel and then suddenly an audible
>> clanging sound emanates from the engine. We immediately pull over to
>> investigate and despite much head scratching nothing significant
>> can be
>> found. I disconnect the fan belt and also eliminate a rocker
>> hitting the
>> rocker cover.
>>
>>
>> Six and a half hours of sitting in the back seats of a tilt tray
>> truck we
>> arrive back home.
>>
>>
>> Today I removed the rocker cover and all valves are opening
>> correctly,
> plus
>> the noise is still there. So what do we think the noise is? Oil
>> pressure
> is
>> still good, so it probably isn't a slipped big end. It is
>> definitely not
>> coming from the gearbox.
>>
>>
>> Without taking the engine out, my guess is a broken crankshaft.
>> What's
>> yours?
>>
>>
>> Hoo Roo
>>
>>
>> Patrick
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