Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: chrisdb on 01 May 2011, 07:42:07

Title: What can cause oil in water?
Post by: chrisdb on 01 May 2011, 07:42:07
A few months ago I had oil in the water caused by the oil cooler. I replaced the oil cooler but noticed a few weeks ago that I am still getting lots of oil in the water.

On checking I noticed some fresh oil around the middle left hand bolt of the oil cooler cover and some traces of oil around the oil cooler cover nut. I replaced the oil seal washers again - the new oil cooler did not seem to be leaking and I flushed the cooling system, but I'm still getting oil in the water.

The only other reason I know of for this is the head gasket but I don't think it is this because the enginge runs very smoothly. Any ideas how i can diagnode the fault?
Title: Re: What can cause oil in water?
Post by: Elite Pete on 01 May 2011, 08:29:17
Was the replacement oil cooler a new or secondhand one?
Title: Re: What can cause oil in water?
Post by: Jimbob on 01 May 2011, 09:09:15
Have you ever had definatley crystal clear water?

they take one hell of a lot of flushing, could just be your still getting the sediment out?

Try some forte biodegreaser or similar for a set of flushes?
Title: Re: What can cause oil in water?
Post by: feeutfo on 01 May 2011, 09:37:22
Needs more flushing by the sound of it, as said.
Title: Re: What can cause oil in water?
Post by: chrisdb on 01 May 2011, 09:46:39
Thanks guys. It was a new genuine VX oil cooler. I used the Holts Speedflush, but I did only flush it once so I'll give it a good flushing again.  :y
Title: Re: What can cause oil in water?
Post by: feeutfo on 01 May 2011, 10:14:16
May need several attempts over a couple of weekends to clear it. And even then....
Title: Re: What can cause oil in water?
Post by: Elite Pete on 01 May 2011, 11:39:51
As everyone else has said, it can take many many flushes to clear the system of oil, its the worst part of the job :(
Title: Re: What can cause oil in water?
Post by: chrisdb on 01 May 2011, 19:47:30
Thanks guys, will give it some good flushes. At least it sounds like nothing too bad.  :)
Title: Re: What can cause oil in water?
Post by: DTC on 04 May 2011, 22:28:05
Could someone have ever put rad weld in there? It can give an appearance like oil and there may be traces of a copper slip like sediment in the expansion tank.
i recently bought a 2.6 and was diagnosing oil cooler and all sorts. A good flushing and i mean over 9 hours whilst valeting the car including running up to temp with fresh water and completely flushing the matrix repeatedly had it crystal clear.
Title: Re: What can cause oil in water?
Post by: dragonlord on 05 May 2011, 00:09:12
may have still had some in there or stuck in heater matrix

ie had heater on while it was leaking the not having it one

plus it hard to fully drain the v6 with out getting at the coolant pipe right at back of engine
it a bugger to flush

i got court out on sticking old blue coolant in after i thort  id drained it fully and flushed it

only to find out i hadn't and spent another week end
flushing the sludge out from it mixing

it was at for 2 dat day with rad flush and keeping stciking the hose pipe on full blast in every water pipe i could
for a few days
Title: Re: What can cause oil in water?
Post by: TheBoy on 05 May 2011, 08:40:35
I would say that Holts Speedflush is absolutely no good in this case.  Can't really think of a case when it does have a use, but thats another story ;D


In this case, repeatedly flush the system with plain water, about 10 times a day for 2 or 3 days. It should start to come clearer.  Then flush through with a special oil cooler failure flushing agent - Forte do one called something like Forte Coolant Flush for oil cooler failures ;D - following instructions.

At the end, remember to get the antifreeze mix back to 50:50 to stop internal corrosion.
Title: Re: What can cause oil in water?
Post by: chrisdb on 05 May 2011, 21:09:08
Thanks everyone!

I'll do lots of flushing over the weekend. The water was always clear prior to the oil cooler failure so I'm pretty sure there's nothing nasty hiding in the radiator ;D I did not realise how much flushing it would take. It's payday next week so I might do the cambelt and water pump then as that should let a lot of water out. I've never managed to get more than around 3 literes of antifreeze/water in it so I guessed the engine retains a lot of water. Plus the front of the car is always higher than the back due to the slope on my drive!
Title: Re: What can cause oil in water?
Post by: Andy B on 05 May 2011, 21:12:02
Quote
..... Plus the front of the car is always higher than the back due to the slope on my drive!

Reverse onto your drive when you drain it  ;) ;) ;)
Title: Re: What can cause oil in water?
Post by: Entwood on 05 May 2011, 21:21:49
One of the problems that can ocur is folks "flush" incorrectly .  There is NO POINT in running a hose in the top and opening the drain valve ... all that happens is fresh water runs out..... taking the path of least resistance.

The ONLY way to flush an Omega....

**
Remove header cap and open drain valve.
Wait until water flow ceases, close drain valve
Fill with clean water to correct mark on header tank, leave header tank cap OFF
Start engine and allow to idle
Set heating/air con to max heat
Wait until thermostat opens as indicated by top hose getting warm
Squeeze top hose repeatedly (known as "burping" helps to remove airlocks)
If water level drops in header tank, top up with fresh water.
When system is at normal temperature switch engine off
Leave to stand for 30 minutes to cool down

Repeat from **

If you are trying to remove oil residue then a low suds biological detergent can be added to the fresh water to assist, but do NOT allow the water to "foam" as this will cause localised overheating as foam does not transfer heat.

It took over 20 odd repetions of this procedure to - eventually - clean a 2.5 V6 that had an oil cooler fail on my mates car.

Any other method leaves parts of the engine isolated from the process and these will remain contaminated

HTH
Title: Re: What can cause oil in water?
Post by: chrisdb on 05 May 2011, 21:33:20
That makes a lot of sense when you think about it! That would make a good How To article.
Title: Re: What can cause oil in water?
Post by: ffcgary1 on 05 May 2011, 23:11:21
If you are trying to remove oil residue then a low suds biological detergent can be added to the fresh water to assist.
Quote

 as already suggested chris.