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[VXL V6]

We all know the usual misdiagnosis of HG's on V6's but there is also a growing number of 1998 (S) reg V6's that have had HG failures as well. 

[Steve s reg omega]

PM'd Mr Guffer already, Just looked at the three plugs on the drivers side and the third (nearest the Fan) has oil in the plug well and the first has a small amount, the centre is dry. Re: the cam covers the gaskets were changed this year for similar problems and I'd already changed the HBV

[octanejunkie]

Are there signs of oil mixing with water (light brown milky fluid) in the header tank, or on the oil dipstick? If its losing fluids, they have to be going somewhere..
Does the car have smelly white smoke from the exhaust, even when fully warmed up? This will indicate coolant getting into the cylinders and burning off. Drips from the exhaust back box are condensation inside the exhaust, and certainly no indication of head gasket failure.
Also, the v6's are quite prone to getting a bit of sludge around the filler cap, its quite normal.
For clarification, did you overheat the car? If so, how bad/how long?
As others have said, the oil cooler is prime candidate for oil/water mixing.
IF you have blown the head gasket, then it is quite an involved, time consuming job, but not desperately complicated. The worst bit is getting the engine timed up properly when fitting the new belt.
Costs involved will be a new gasket set, a timing belt kit, skimming the heads, spark plugs, oil and filter, fresh coolant. Lets say that lot will be somewhere in the region of £400, plus there is the labour. I personally would allow a full day, possibly longer to do this job. A garage might quote you 6-8 hours maybe..
If the heads need skimming (which is a good possibility after an overheat), you may well have to take all the valves etc out.
Plus there is the danger of snapping exhaust bolts, and other unforeseen dilemmas.
If this all sounds a bit doom and gloom, well, it should. Omegas are not worth a great deal even in great condition and full running order.
There will be those who are the type that'll keep a car forever and fork out for the job.
Then there will be those who might choose to chuck another complete, good engine in there. That is, if the rest of the car is really good with no rot and sound drive train.
It pains me to say that the most practical course of action is to perhaps buy another sound car, and maybe swap around good bits from yours and sell on parts from the other to recoup the investment.

Having said all that and depressed the hell out of you, there is still a good chance it might be something relatively simple like the aforementioned oil cooler..
How attached are you to that particular car...?

[Steve s reg omega]

Hi Guys thanks for the good reading, I 've just removed the N/S 3 plugs and found enough oil in 4 & 5 as well (nearest fan and centre) 6 was dry. Done the compression test and starting from the O/S nearest Bulk Head and working anticlockwise 1-6 the reading are as follows: 1 - 230 (15)  2 - 200 (14)  3 - 200 (14)  4 - 240 (16)  5 - 245 (17)  6 - 195 (14)
A nice range of numbers and according to Haynes book of death this doesn't necessarily mean the head(s) but they need to come off for a de-coke any way?? any ideas? Also I had the car running for about half an hour last night with a clean piece of card underneath and the oil drips are showing from the back of the engine and N/S but I need to remove the sh*t shield to double check!!

[Steve s reg omega]

Forgot to mention it's never overheated and the last long drive was from Malvern to Portsmouth!

[05omegav6]

Ok, that's a bit confusing as the cylinders are numbered differently... bank one (uk drivers side) is 1,3,5 from the front, bank 2 (uk passenger side) is 2,4,6 from the front

N/S are 2,4,6. So you have oil in the wells of 2 and 4. New cam cover gaskets needed, along with thorough breather clean. External oil leaks are almost certainly from the cam covers.

Compression ratios... actual cylinder numbers...

1. 200 (14)
2. 240 (16)
3. 200 (14)
4. 245 (17)
5. 230 (15)
6. 195 (14)

These don't actually tell you anything, as when the gaskets fail on these engines, the fire rings stay intact, so compression is unaffected. The gaskets fail at the water ways towards the back of the head, allowing coolant to escape out and down the block.

Any oil in the coolant? If so, the oil cooler is failing. Not a head gasket symptom on these engines...

[Steve s reg omega]

Hiya, I had the rocker cover gaskets changed this year and there doesn't seem to be any oil in the water. The dip stick looks clean and the only cream is in the filler cap! 

[kevinp58]

Hi Guys thanks for the good reading, I 've just removed the N/S 3 plugs and found enough oil in 4 & 5 as well (nearest fan and centre) 6 was dry. Done the compression test and starting from the O/S nearest Bulk Head and working anticlockwise 1-6 the reading are as follows: 1 - 230 (15)  2 - 200 (14)  3 - 200 (14)  4 - 240 (16)  5 - 245 (17)  6 - 195 (14)
A nice range of numbers and according to Haynes book of death this doesn't necessarily mean the head(s) but they need to come off for a de-coke any way?? any ideas? Also I had the car running for about half an hour last night with a clean piece of card underneath and the oil drips are showing from the back of the engine and N/S but I need to remove the sh*t shield to double check!!

WHY  you really don't need to do that to modern engines. 

[Steve s reg omega]

That's just what the book said, need suggestions as the Haynes is only useful sometimes for procedures

[05omegav6]

Hiya, I had the rocker cover gaskets changed this year and there doesn't seem to be any oil in the water. The dip stick looks clean and the only cream is in the filler cap! 

If you found oil in the plug wells then the cam cover gaskets need doing again, and properly 

No oil in coolant is a good thing, any coolant loss from the back of the 246 head less so, as this is probably the head gasket.

Has Guffer seen it yet?

[Webby the Bear]

Sorry not hijacking......... but Taxi, quick question....

If the HG fails behind the 246 bank would there be any other symptoms besides coolant loss? Just out of interest

[05omegav6]

Sorry not hijacking......... but Taxi, quick question....

If the HG fails behind the 246 bank would there be any other symptoms besides coolant loss? Just out of interest

Probably not, hence the continual misconception when it comes to oil cooler failures being misdiagnosed as hg failure.

MarksDTM posted a pic a while back explaining this very point... that with the angle of the V, combined with the fact that water flows on the low side, and oil on the high side and could therefore never mix. The gasket almost always rotting out on the rear corner on the exhaust side, which is where the water escapes from the join between head and block.

[Webby the Bear]

Sorry not hijacking......... but Taxi, quick question....

If the HG fails behind the 246 bank would there be any other symptoms besides coolant loss? Just out of interest

Probably not, hence the continual misconception when it comes to oil cooler failures being misdiagnosed as hg failure.

MarksDTM posted a pic a while back explaining this very point... that with the angle of the V, combined with the fact that water flows on the low side, and oil on the high side and could therefore never mix. The gasket almost always rotting out on the rear corner on the exhaust side, which is where the water escapes from the join between head and block.

So basically if the HG fails on a V6 Omega you wont get the standard coolant in the oil because of what you've just explained ?

Cheers mate

[05omegav6]

Zactly

[Steve s reg omega]

Love the conversations going on. After the kids thing in the morning and if the weather lets me the inlet manifold's going to come off so I can look further. I've never done a V6 so this will be interesting As I'm not using it at the moment I've got the time