Peugeot 207 1.4 - suspected seized engine

[Ady2021]

Good idea about the stethoscope. I have just dug out a piece of tube and had a listen but the there is too much noise from the rest of the engine to be able to pin-point the noise. It does sound like something metal trying to rip itself up. Looks like a strip down is the only way with this one. Will start with getting the cylinder head off and going from there.

[Michel]

Can you explain the bad main bearing noise in more detail please Jim? As it is your description sounds like my grandad sleeping.

Sounds like a washing machine with a couple of pairs of trainers in a pillowcase on spin. Like a deep, muffled, rumbling noise.

[Ady2021]

Ok. That makes sense if the crank is jumping up and down while it is trying to rotate in a loose set of worn bearings.

[xantia_v6]

On the way to pulling the head, you might want to remove the timing belt and check that all of the rollers and water pump spin quietly.

[ozvtr]

That noise is very loud. By that I mean, it is louder than any noise that would come from inside the engine.
I don't think it's coming from inside the engine.
Maybe the timing belt idler/tensioner pulley? Is the noise coming from the crank shaft pulley end of the engine?
Remove the accessory drive belt, the crankshaft pulley and the lower timing belt cover. Run the engine like you did without the accessory drive belt.

[MattBLancs]

Good idea about the stethoscope. I have just dug out a piece of tube and had a listen but the there is too much noise from the rest of the engine to be able to pin-point the noise. It does sound like something metal trying to rip itself up. Looks like a strip down is the only way with this one. Will start with getting the cylinder head off and going from there.

Stethoscope alternatives:

- long screwdriver
- piece of wood (broom handly diameter or thinner, maybe even a garden cane)
- piece of metal (m6 threaded rod about ideal)

Basically something solid to press against components in the engine bay, put your ear to the other end. Obviously, caution round the belts and to any positive electrical connections (starter solenoid, alternator output connection obvious main ones) if using a metal stethoscope.

Consider it all sounds rather odd first time you try this!

[Rp0thejester]

I use a similar trick at work when I'm drilling deep holes, vibrations can give you an idea of what is going on

[Gibbo2286]

One thing we haven't mentioned is the crankshaft pully outer and inner parting company.

[Ady2021]

I have now had the chance to pull the cylinder head off of the car and have been checking everything as I have been dissembling the car.
What I have checked so far:
1. Serpentine belt, all the pullies and ancillaries are ok
2. Timing belt, all the pullies and the water pump are ok
3. Camshaft seems to rotate smoothly with no rough spots and all the lobes are good
4. Cylinder walls seem very good which is remarkable considering the amount of oil it was burning
5. Piston crowns are very good with no holes

The only thing I have found so far is the rocker shaft seems to have some rough spots as you try to rotate the rocker arms. I have done a brief inspection and there is some wear in the rocker assembly which makes me wonder if it was trying to seize. It is questionable if that would cause all that noise though!

Is it ok to polish any wear and rough spots out of the rocker shaft and rocker arms or do you advise getting another one from the scrap yard?

I will put new rings in the car and rebuild it and hope I find the problem as I am going. I really can not find any reason why this engine could not be made to last another 50k miles as all the components I have checked so far are very good for their age.

[ozvtr]

Can you post photos of the wear?
Rough spots usually means galling of the surface. You should be able to spot that on the surface of the rocker shaft.
If you are spinning the rockers around the shaft in a complete circle, that "roughness" is "oil gunk" that has built up in the areas of the shaft where the inner of the rocker does not normally contact the shaft.
The rockers might not come off the shaft for the same reason, gunk building up on either side of the rocker on the shaft.
Usual test is to run your fingernail over the damage and see if your nail catches, or feel if there are ridges.
The rockers will usually polish the surface of the shaft, typically one side more than the other, but anything worse than that is not good. If that's the case the inner of the rocker may be damaged too.
I cant see how the rockers could cause a squealing sound. They go up and down!? Maybe a chirping sound??

[Ady2021]

Apologies I have not given an update before now. The good news is, the engine is fixed but it has taken a lot of work.

I stripped the engine as far as I could without removing it from the car and so it is only the crankshaft and main bearings that have not been disturbed. All the parts were then cleaned and checked and the cylinders were honed before fitting new piston rings. The cylinder head was completely stripped and de-coked before rebuilding with new valve stem seals. The catalytic converter has been soaked and is now completely unblocked. The engine was then finally rebuild with a new head gasket and sump. It finally sprang into life the first turn of the key and sounds better that it ever did with no smoke from the exhaust. The whole job cost me less than £150 in parts and was a much better option than a second hand engine in my opinion. I did try to get a second hand engine first but no local scrap yard had one that was not burning oil and so rebuilding seemed the better option.

I did find out what was causing the squealing sound. It was the catalytic converter which was completely blocked causing the exhaust gases to be squeezed out of a gap in the exhaust gasket at high pressure and therefore acting like a whistle.

A word or warning to anyone thinking about doing this job. Make sure you measure the thickness of the old piston rings before ordering new ones. I always thought my engine was a TU3A engine and so the rings should have been 1.75, 2, 3 mm thick but they were not. Mine were 1.5, 1.5, 2.5 mm which is what is used on the TU3JP engine and so does not make sense for a 2008 car. You will need four sets of piston rings for all the cylinders at about £60 in total.

I have captured loads of photos and can put together a bit of a write-up about the process of replacing the piston rings if anybody is interested?

[CitroJim]

Excellent news! Well done and excellent work... I've seen a blocked cat on a Peugeot 306 diesel once before. It did not affect the running of the engine at idle and slow speeds very much but it sure robbed it of power at anything above about 1/4 throttle!

Like you, we spotted it by seeing smoke escape around the cat to manifold joint...

[MattBLancs]

Thanks for feeding back your eventual cure and glad to hear it is better than ever!

Always enjoy a look any pictures, not had opportunity to dig into a TU yet. No need of a write up as know that's a fair undertaking.

Not heard of a petrol catalyst blocking before, (diesels yes) Wonder if the oil burning was cause of the catalyst accumulating material until it caused an issue in olita own right??
In any case, the deep dig into the engine you completed should have eliminated that and so shouldn't have a repeat of the same issue.

I'd have tried a second hand engine but agree your comparative costs (£150 for what you've done versus £180 untested engine + all the sensible things to replace on that, timing belt, water pump etc) then you definitely picked a better way forward!

[darbuck]

Great to hear you got sorted, the oil will destroy a cat fairly quickly. Great work just shows the throw away mentality we've all become accustomed to in recent years is often not the best option. Hopefully you will get a few years out of it now.
I am just coming to the end of a similar journey myself.

[ozvtr]

Good work.

Did you get an "aging catalyst" DTC? Should have. Oil consumption is the No1 killer of catalytic converters. Do you have a pic of the blockage?

How did you spot the piston ring problem? Bought a set and they didn't fit? Or were you given options?

Were the rings stuck to the piston or free?