Citroen XM Forum

An update....

It only gets worse.
Don't show these to the owner - he'll only want to re-use the oil at the top!

Perhaps someone has some kit for pressure testing a block in situ?

Hindsight is a wonderful thing but in the real world I would start easy and then look at the pay to test items so oil coolers for starters, what do the piston crowns look like? Any really clean shiny ones?
If there was a failure to proceed then I'm guessing the engine got hydro locked which means the water is entering from the head gasket, head or inlet tract.

Sorry ive not read back as im just on a plastering break here but why did the engine finally stop?

I personally would call it a day on this engine now, but find the problem first so you can sell the spares off, get to the local scrapyard and buy yourself an engine from an accident damaged car and slot it in, the damage to all bearings will be significant if not visible. That's just me though, I can understand where your comi ng from.

If there are no clean piston crowns I would check all oil coolers as said, make sure he hasn't had a blond moment and dumped water in the oil filler too, visually inspect the cylinder head when cleaned for cracks and the block although unlikely, I would think worst case is the head air locked due to water loss, overheated and cracked which at a guess would happen around the exhaust valve seats. Any pictures of the old head gasket faces? And uncleaned head and block mating faces?

Best of luck, wish I had friends like you

D

White Exec wrote:It only gets worse.
Don't show these to the owner - he'll only want to re-use the oil at the top!

Perhaps someone has some kit for pressure testing a block in situ?

A true Yorkshire lad would, let's face it the oil has just been washed, its good to go again..............

D

Dean's post crossed mine, and is interesting. Could he have got oil and water fillers confused?
Agree with Dean...Unless the exact cause can be found, sensible simply to replace the engine, which would never be AOK after all that, anyway.
Oil cooler not likely to be the fault, as oil pressure always exceeds coolant pressure - so oil can be injected into the coolant, but not the other way round......unless oil pressure is almost non-existent, that is.

True about the oil cooler there would be Mayo in the header tank but after shutdown it can run the other way, so much water though......................

D

White Exec wrote:Dean's post crossed mine, and is interesting. Could he have got oil and water fillers confused?
Agree with Dean...Unless the exact cause can be found, sensible simply to replace the engine, which would never be AOK after all that, anyway.
Oil cooler not likely to be the fault, as oil pressure always exceeds coolant pressure - so oil can be injected into the coolant, but not the other way round......unless oil pressure is almost non-existent, that is.

I doubt he got the fillers confused; he's sufficiently savvy to know what fluids go where. But I suppose anything is possible, if you're not concentrating.

The problem with replacing the engine is :

Finding one !
Affording one !
Time/effort in removing existing engine.
Time/effort in installing replacement engine
Not knowing how good any replacement engine is (could be buying another abused example)

My thinking is this :

Get the head pressure-tested, while it's still off.
Remove the sump, and inspect the crank / oil-pump / oil-pump drive-chain
If possible; overhaul the oil-pump
Clean-up inside the sump, and refit.

If the bottom end is viable; then we continue with the rebuild.

Though how we pressure-test the block; I don't know.

The piston crowns were generally as you'd expect; and have since been cleaned up. Though I vaguely recall one piston crown being clean; will confer with my mate.

Still have the original head-gasket; so can photograph that.

The head has been skimmed; so no evidence remains there.

The bores actually look in good shape, surprisingly; can still see the cross-hatching

We're off to Peugeot in the morning; try and get to the bottom of this "camshaft oil-suppy non-return valve" issue. Suspect we'll then move on to sump removal, when we get back to the car.

But I agree; we need to ascertain what caused the engine to fail; or at least eliminate suspects (like the head).

Keep the advice (and encouragement) coming

Justin

From what I can see on Service Citroen, using the C4 as the vehicle, the EW10A engine with power outputs of 143 or 180 Bhp uses non return valve no. 025316, with the valve mounted in the end of the head. For the engine with 138bhp, the valve is mounted in the centre of the head and is p/n 025317. (3.5 x 12-22)

EDIT:
I've clipped your original post on this. It appears you have the 138Bhp engine (EW10J4) that should use p/n 025317.

jeastham wrote: So come last Saturday, designated "H-day" (for refitting the rebuilt head - I had my reservations, but it's his call); we were unable to proceed, because the "cam-shaft oil-supply non-return valve", that sits in the under-side of the head, didn't fit into its aperture (WAY too big).

Never had to do this - block pressure test.
Wonder whether it would simply be possible to bolt down a piece of formica/laminate covered board on top of the block, with some silicone/polyurethane sealant carefully applied around the water channels, and allowed to set.
Block off the water pipe connections to the block, and apply air pressure to one of them (or a drain point) and see whether it drops or not.
Maybe repeat with water pressure, if necessary, to see where it leaks.
Cheesewire the board off afterwards.

Just an idea.

I like the idea but that is a lot of work.....