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Omega General Help / Re: Mv6 3.0 oily water
« on: 01 February 2023, 11:17:25 »
Would a 3.2 cover work its magic? There are no 2.5 or 3.0 scrapped in Sweden.
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And intermittent coolant loss is far more likely to be HBV, and is easily checked visually.HBV is brand new (was spraying coolant like a mist), double-check and the engine watery just at the middle of the "v" when leaking.
But as you have to change the oil cooler anyway, you'd be radio rental not to change the cover plate.
Top tip when changing the oil cooler - do not bend the pipes. Do it properly and undo the pipes near the oil filiter. Bending them will stress them enough to cause them to leak at the oil filter end anyway, and also make them a complete arse to refit. No need to ask how I know that, after I chose to ignore the good advice here
You misunderstood.So, yes. New plate and oil cooler. Thanks.
1. Failure of the cooler = oil in the coolant
2. Failure of the cover plate = coolant loss
2a. Failure of the head gasket as described = coolant loss
2b. Failure of the HBV = coolant loss.
1 is fixed by replacing the oil cooler (and flushing the cooling system with dishwasher tablets about 26 times.
2. Is not fixed with sealant. But rather replacing the porous aluminium plate with a new one. And maintain it by renewing the correct coolant every four years.
You need to find the source of the coolant leak. A mirror on a tick so you can see the rear of the engine can be helpful. Or pressurise with compressed air is even better.Yes, my plan is to take the plenum+DIS-pack off (to see what's happening), then pressurise, let us pray.
After that, you definitely need a new oil cooler. And then lots and lots of flushing of the cooling system to get rid of the oil from it.
Oh yesexcellent, enough hope to start the process and find out the false hypostasis is a way to go.
Its pretty much impossible for oil to get into the water via a failed headgasket, its usually the other way round (water in the oil) or water in the bores, or just water leaking.Awesome answer. So there might be a chance in hell I'm on the wrong track and just need to seal the oil cooker.
The basics are that a headgasket has only one high pressure area for oil (to feed oil to the cam bearings and followers) and its very well protected by integrated rings and seals, to get oil into the water jacket would require this high pressure oil feed area to fail and get into the above atmospheric pressure coolant (which it is most of the time).
The one place oil can get into the coolant is the oil cooler
MarkDTM did a pretty detailed post regarding the V6 HG failure.You're a champ for the recap, thank you very much. Dreading to pull it apart in a parking lot though, but what can one do...
Basically, when it fails on the Omega it does so in such a way that coolant leaks out of the gasket rather than mixing with oil. When the HG failure gets worse, the failure point allows water into the #6 cylinder but not the oil passages because where the gasket fails first is between the water passage and the back of the engine and, then secondly, between the water passage and the cyinder. This means that it leaks coolant externally as the mode of failure and in to the cylinder only when the engine is running and at no point do the water and oil passages become connected.
This is in contrast to the oil cooler fail which sees the oil pump force oil into the cooler without allowing coolant into the oil, even though this is often misdiagnosed as HG failure.
Once the head comes off, the point of failure will be immediately obvious, at on the back left corner.
In which case there's some good news and some bad news.Double up the bad news, only got outside parking. On a crossroad, either i fix it (dyi) or I put it aside and wait for a time to place another engine in. Lovely machine except the engine at this moment.
The good news is that you know what the problem is
The bad news?
Well, you know what the problem is...
Third time's a charm, it's most likely not the HBV as I've allready changed the piece. Checked all hoses and non is wet, while there were liquid around the block/head. Running down the left side of the gearbox.Panic not, that's usually a weep.Oil cooler failure is typically seen by oil in the coolant[but not the other way round]swapping one is not a particularly difficult job and I believe there's a guide on here in the maintenance section on how to do it.Said to the one having a 98 mv6 with leakage at pressure behind the head/block. BAH
I understand that some cars[about 1998?] had a problem with head gaskets leaking to the outside of the head/block towards the rear but others would know better about this than me.
When the HBV fails it will dump coolant as fast as the waterpump can supply it. As you've recently discovered.
Oil cooler failure is typically seen by oil in the coolant[but not the other way round]swapping one is not a particularly difficult job and I believe there's a guide on here in the maintenance section on how to do it.Said to the one having a 98 mv6 with leakage at pressure behind the head/block. BAH
I understand that some cars[about 1998?] had a problem with head gaskets leaking to the outside of the head/block towards the rear but others would know better about this than me.