Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: TheBoy on 20 August 2006, 22:37:37

Title: Oil Cooler of HG
Post by: TheBoy on 20 August 2006, 22:37:37
Seeing as sometimes water can end up in oil sometimes with oil cooler failure, is there a way to know for definate whether a failure is oil cooler or HG?
Title: Re: Oil Cooler of HG
Post by: omegaV6CD on 20 August 2006, 23:07:26
Quote
Seeing as sometimes water can end up in oil sometimes with oil cooler failure, is there a way to know for definate whether a failure is oil cooler or HG?

Given the fact that the water pressure wouldn't exceed 2bar and the oil pressure can reach 5 bar i would say that if the oil cooler is gone then you will have oil in water as well as water in the oil. So if you see water in the oil is either condesation or head gasket, or too old oil that has lost its properties.
The only way that water can enter into the oil via the oil cooler is when the engine is stopped and hot and therefore the oil pressure is 0 while you still have 0.8ish bar coolant pressure. I donno if i have been clear but what i want to say is that if there is a hole then fluids can be transferred both sides depending on pressure and sometimes viscosity.
Title: Re: Oil Cooler of HG
Post by: RonaldMcBurger on 20 August 2006, 23:25:56
Speaking entirely hyperthetically here, lets say you bought an Omega off Ebay for example. And that red 2.5v6 Omega happened to have brown gooo in the header tank, you can be 100% sure that either the oil cooler has gon, on someone at the auction house took a dump in the header tank. My money is on the oil cooler.

PM to Mark. He has just done the oil cooler on his MV6. I am sure he will know exactly what to check anfd where.

And, I am still wiating for my commission! ;) hyperthetically of course.

Title: Re: Oil Cooler of HG
Post by: omegaV6CD on 20 August 2006, 23:28:08
Quote
Speaking entirely hyperthetically here, lets say you bought an Omega off Ebay for example. And that red 2.5v6 Omega happened to have brown gooo in the header tank, you can be 100% sure that either the oil cooler has gon, on someone at the auction house took a dump in the header tank. My money is on the oil cooler.

PM to Mark. He has just done the oil cooler on his MV6. I am sure he will know exactly what to check anfd where.

And, I am still wiating for my commission! ;) hyperthetically of course.

;D ;D ;D
Title: Re: Oil Cooler of HG
Post by: tunnie on 20 August 2006, 23:38:04
Quote
Speaking entirely hyperthetically here, lets say you bought an Omega off Ebay for example. And that red 2.5v6 Omega happened to have brown gooo in the header tank, you can be 100% sure that either the oil cooler has gon, on someone at the auction house took a dump in the header tank. My money is on the oil cooler.

PM to Mark. He has just done the oil cooler on his MV6. I am sure he will know exactly what to check anfd where.

And, I am still wiating for my commission! ;) hyperthetically of course.


In this purly theoretical discussion, it might interest you to know hyperthetically speaking i spotted it first and had an offer accepted!  ;)
Title: Re: Oil Cooler of HG
Post by: Markjay on 21 August 2006, 00:45:20
Quote
Seeing as sometimes water can end up in oil sometimes with oil cooler failure, is there a way to know for definate whether a failure is oil cooler or HG?

As far as I can see all of these will point conclusively to head gasket problem - and not oil cooler issues.

1. The obvious thing to do is a cylinder compression test, looking for a single cylinder or adjacent pair with lower compression than the rest. A dry-and-wet test will confirm that any low compression isn’t the result of worn piston rings (though theoretically under rare circumstances you could have an oil cooler problem AND an unrelated leaky valve, which will look like a blown head gasket...).

2. The advice usually given by Car Mechanics Magazine is to ask an MOT testing station to lower a gas analyzer into the expansion tank (not actually touching the liquid) while the engine is running, any sign of exhaust gasses detected will indicate a definite head gasket failure.

3. I noticed in the past that when a head gasket problem becomes severe (that was on a 4-pot 8v TC Alfa-Romeo unit), if you place your hand over the exhaust you can feel condensation which is actually coolant droplets – and they will have a distinct smell of antifreeze. Also, you could sometimes smell the antifreeze on the spark plugs.




Title: Re: Oil Cooler of HG
Post by: JasonH on 21 August 2006, 21:11:13
I believe there are now chemical kits that fit to the coolant expansion tank. If exhaust gases are detected the liquid changes colour.

No idea on cost or availability - but seen them used on telly.....
Title: Re: Oil Cooler of HG
Post by: JasonH on 21 August 2006, 21:13:07
Here's one:

http://www.arrowheadradiator.com/head_gasket_or_combustion_leak_test.htm
Title: Re: Oil Cooler of HG
Post by: TheBoy on 21 August 2006, 21:14:41
I reckon its the oil cooler, as just dropped the oil out of it, and not a sign of water in it :)
Title: Re: Oil Cooler of HG
Post by: Tezray on 21 August 2006, 21:49:59
Could you not also use mileage as an indicator of HG/oil cooler failure? For example, mine had covered 158,005 miles when the headgasket went, if yours had say covered 135,000 or less wouldn't it be fairly safe to say it's most likely to be oil cooler failure?

Exhaust fumes in the header tank are a very definite sign of HG, mine STANK when it finaly kicked the bucket!!
Title: Re: Oil Cooler of HG
Post by: Timbuk on 24 August 2006, 00:03:54
Just done my oil cooler, no water in oil, brown toffee oozing ( and i mean oozing ) from header tank and just to throw a spanner in the mileage theory mine has also done 158000
Title: Re: Oil Cooler of HG
Post by: Marks DTM Calib on 24 August 2006, 08:36:06
I strongly suspect that head gasket failure will be closer related to age and servicing than mileage....