Technical rattling head

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Technical rattling head

glenn2602

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Suddenly, for no apparent reason, a rattle suddenly appeared - coming from somewhere in the cylinder head. It began by sounding like a knife blade stuck in a rotating fan.. and of course, the car won't run.

The injector housing/rocker cover has been removed and all the tappets and springs seem fine. Obviously the head now needs removing..

I sometimes wonder if it's all worth it..
 

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A broken valve 'piece' or maybe a bit of a valve seat.

The car was fine when it was parked up. An hour later, when started .. such a horrendous noise.

I've done maybe 250 miles in this car since I bought it at auction 18 months ago. It was a 30,000 mile one-owner car, but had obviously stood in a garage for a long time. At the time of buying it the tappets sounded like machine guns and were exceptionally loud.

The spring loaded ends in the tappets had seized. I replaced them at the time. This isn't the OHV engine...

I reckon that the hammering of the seized tappets (the clearances would have been way out..) has caused stress or damage in the valve foot or seat and has now decided to break up.

Hopefully that's all it will be. I'll find out when I get round to lifting the head. There's definitely something rattling around in there.

Low mileage cars aren't always the bargains you might imagine. Things seize and go wrong just through standing.
 
The picture is the 900cc OHV engine, not the 1100 OHC FIRE. It therefore has hydraulic tappets in the block above the camshaft. When new these gave a few problems and some were replaced under warranty.
Hydraulic tappets like to be used. If stood, they can gum up, giving clearances and noise. In normal use there should be little or no clearance at the rocker, so check this, as it may highlight lazy tappets.
Then do a compression test, before removing the head. These two checks may remove the need to lift the head.
Report back.
 
I had the same problem with my Cinqucento SX when I purchased it
Flushed the engine oil with a STP product , new oil filter and good quality oil and straight away quiet as a mouse
 
I meant to say it's not an overhead cam ..

I agree with portland bill about the tappets .. and it really did sound like something bouncing around on a piston. I'm going to have to lift the head no matter what.
 
I meant to say it's not an overhead cam ..

I agree with portland bill about the tappets .. and it really did sound like something bouncing around on a piston. I'm going to have to lift the head no matter what.

Not if a flush works. As suggested above, try a branded engine flush, which hopefully will clean out the tiny oil holes in the tappets, then refill with good oil of correct grade. Don't be tempted to go a higher viscosity number. Tappets most likely just glued up due to lack of use.

Just looked at my Haynes Cinq manual, the hydraulic tappets are in the rockers. (I thought they were in the block)
They can be extracted from each rocker, and can then be inspected, and dumped into a bath of solvent if necessary. Presumably they are fed through drillings in the rocker shaft, so remove the whole assembly, dismantle, and ensure all oilways are clean. Removal of head only necessary if oil feed from block is blocked.
 
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I understand what you mean, bill.

The tappets were changed when I bought the car at auction. They were well and truly seized ..

It wasn't a 'tappety' noise .. I can't see how a horseshoe got into a cylinder bore, but it certainly sounded like there was one bouncing around in there..

It was one of those 'Oh no!' noises that come from below the cylinder head... I'll find out when I eventually lift the head
 
I did have a Kia with a blocked hydraulic tappet which sounded like a heavy machine gun until I had flushed the oil twice. Previous owner had no service history for over 30k miles. Oil was like molasses. Engine was fine for another 60k until bodywork caused a trip to the scrapyard.
Conversely I had a Lotus twin cam which ate an airbox nut and only made a tappet type sound. Head, piston and liner were all scrap. Ouch.
Could be worth flushing. Maybe...
 
It wasn't a 'tappety' noise .. I can't see how a horseshoe got into a cylinder bore, but it certainly sounded like there was one bouncing around in there..

It was one of those 'Oh no!' noises that come from below the cylinder head... I'll find out when I eventually lift the head

Have you taken the plugs out yet?
You can often tell a lot by the state of a sparkplug. Especially if when you remove them, one isn't complete...!
 
Well.. lifted the cylinder head and discovered the cause of the rattling/tinkling.

No4 cylinder where the noise began - the spark plug tip was hammered and smashed. It wasn't the broken plug tip that was the cause of the problem, the plug was the result..

There was a small piece of alloy in each bore. The alloy had been well and truly hammered by the pistons of course. In one of the photos you can see pitting/hammering on No4 piston.

There's no damage to any of the bores, or seemingly to the valves and seats. The removed cylinder head was turned upside down and the valves submerged with wd40. The wd40 stayed there, indicating that the seats were holding their seal.

It begs the question where did the alloy come from? The injection unit had been removed to fit a new gasket and I can quite understand accidentally dropping something down through the inlet manifold and it finding its way into a bore. But, I'm 100% positive that nothing was dropped.

The other point would be that bits of alloy were in all four bores. It goes through my mind that bits of alloy swarf were already lying somewhere in the injection unit housing/inlet manifold area, and that the flooding of petrol washed them down. I really, really can't see bits of alloy finding their way down through valve stems. Besides, the inside of the rocker cover was inspected - all seems in order. There's nothing seemingly amiss with the fuel injection housing either.

Water under the bridge now... in the next few days I'll re-inspect everything and then get round to refitting the head. The photos of the 4 bits of alloy, plug, head ..
 

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Were there any small children around last time you had the plugs out?
 
The electrode in No4 was broken off by being hit by whatever was in the bore. What I haven't yet fathomed out is how/why there was a piece in each bore.
 
That's funny purf I was wondering the very same thing if they could be the alloy screw on connector for spark plugs.
 
Not uncommon for stuff to appear in all cylinders. As an inlet valve opens, debris can be ejected into the inlet manifold, and then be drawn into the next cylinder. Quite possible for debris to travel across all cylinders.
When engines fail, debris can often be left in the inlet manifold, to be drawn into the replacement or repaired engine.
So don't spend too much time worrying about it being in all four.
 
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