Cylinder Bores Damaged, Advice on Proceeding??

[briwy]

Looks very much like a faulty casting to me.
Difficult to see how damage like that could be caused without very serious overheating which would have shown up in other ways. If anything had been inside the cylinder then you would expect to see damage to the piston.
Was there any debris in the cylinder?

[321Away]

no debris at all

Julian

[Northern Bongolow]

any idea on the mileage julian. was that bore really dirty when it was split.

[Velocette]

Could a previous owner have put petrol in it by mistake or some other duff fuel? Or even a fuel additive?

[321Away]

vehicle is a 1996 2.5 TD, 80,000 Miles on the clock, regularly serviced.

The actual bore itself was clean, just the top byt the deck as in the pic?

As far as i know, Mick came in and had a coolant alarm fitted about 3 weeks ago after getting coolant loss for previous couple of weeks, then came back last week and confirmed that it was still losing water, he had 1 high temperature incident but not a full blown overheat, did a full re-bleed and told him to keep eye on levels and what i suspected was head/gasket and he came in week later with a steam powered bongo, with clouds of white vapour behind him! Removed head and this is what was found! the valves in no 4 are pitted badly, the valves in 3 show pitting too

Julian

[Northern Bongolow]

is the egr stuck open, so that during warm up its recircing a rich mixture.

[briwy]

If it was mine I'd go for the new head and keep a close watch on overheating and coolant loss.
Might be worth dropping the sump and taking the piston out for a look while the head's off.
Looking at the picture it doesn't appear, judging by the the black carbon line round the top of the bore, that the top piston ring comes into the damaged area.
It also looks like the head gasket sealing ring imprint is clear of the damage.
Was there any sign of water in the oil?
Do these engines have liners or is the bore straight into the block?

[321Away]

If it was mine i would too, HOWEVER as its a customers, dont think either company or customer would be prepared to do that regarding work/waarranty etc the rings DONT come up to the affected area, which looks like its been getting worse, so the question lies with that if this is an ongoing process then will it continue and eventually cause new head/gasket to fail etc the seal ring is just beyond the damaged area, ring is approx 4mm, damaged area is approx 2mm, so not sure i'd trust that it would last if only sealing on 1/2 of the surface, another concern of mine is there will be a portion of the bottom of the gasket exposed to the cylinder etc

Julian

[lazyb5]

That looks like porosity in the casting, we get it from time to time on our castings. Have you had a needle in it to see if it extends beyond what you can see.

[Titan1995]

Again, in my own lump then I would go down the head gasket route.....would be good to do anyway to see what happened.

However, my labour is free so what make all the difference in the world.

At least one would know if a temporary/ permanent repair was effected.