Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: TheBoy on 23 February 2013, 10:48:04

Title: Oil leak
Post by: TheBoy on 23 February 2013, 10:48:04
Silver Bullet still has one. Buggered if I can find it. Its had one for maybe 2-3 yrs.

To resolve:
I've changed rocker gaskets, no change (old ones still soft).
Front crank seal (in desperation)
Resealed upper and lower sumps
Valley looks clear (when I did rocker gaskets)
Obviously, its had many oil/filter changes.

I cannot locate it.
Title: Re: Oil leak
Post by: Steve B on 23 February 2013, 11:21:28
looks like your going to have to break it then  :D :D :D :D :D :D :D :D
Title: Re: Oil leak
Post by: symes on 23 February 2013, 11:49:11
check cam seals and banjo seals to cooler  :y
Title: Re: Oil leak
Post by: TheBoy on 23 February 2013, 12:11:39
check cam seals and banjo seals to cooler  :y
Cam seals are fine.

As said in OP, no oil in valley when I changed cam covers a couple of years back (to cure this leak).
Title: Re: Oil leak
Post by: TheBoy on 23 February 2013, 12:12:40
God, just had a moment of doubt then, thinking I'd only checked the front ones.

Then I realised what a plonker I was being ;D. Doh!
Title: Re: Oil leak
Post by: Andy H on 23 February 2013, 13:30:53
Rear crank seal?

The cylinder head gaskets never leak oil..................

Oil level sensor plug? The design of the seal is a bit crap if IRCC.

Old dried oil sitting on the outside of the engine? becomes viscous again when hot?
Title: Re: Oil leak
Post by: YZ250 on 23 February 2013, 14:04:01
Is there a general area to narrow it down?  :-\

Seem to recall it was dipstick tube area ( reference 'O' Rings query) so presuming it's more to the front of the engine.  :-\
As you've checked the most likely culprits, could Camshaft seals be a possibility  :-\ (not the camshaft cover half moon, but the end seal itself ). 
Title: Re: Oil leak
Post by: TheBoy on 23 February 2013, 14:07:33
I seems to sit on top of sump pan.

Well, its everywhere, from undertray back ;D

But I think its on top of sump pan.

Tried cleaning it up, then seeing, but proven unsuccessful so far...
Title: Re: Oil leak
Post by: Andy H on 23 February 2013, 14:32:44
I seems to sit on top of sump pan.

Well, its everywhere, from undertray back ;D

But I think its on top of sump pan.

Tried cleaning it up, then seeing, but proven unsuccessful so far...
Level sensor plug is a push fit through a hole in the top of the sump pan. On one side there is a rubber washer, on the other there is a circlip. It relies on the rubber washer being the right thickness, and having enough elasticity, to give an oil tight seal.
Crap design, pretty much guaranteed to leak when the rubber ages IMO.
Title: Re: Oil leak
Post by: Kevin Wood on 23 February 2013, 15:24:36
That's the integrated rust-proofing system, isn't it? ;D

So, is it appearing on the lip of the sump at the front of the engine?

Could be oil pressure sensor or perhaps block-to-oil pump seal? Upper sump to block seal?

I think the trick would be to thoroughly degrease the area where it's visible then sprinkle it with talc or flour or something and see if you can spot the direction from which it starts to emerge.
Title: Re: Oil leak
Post by: car5car on 23 February 2013, 16:22:50
Pressure washer, engine degreaser spray, brake cleaner, compressed air.
It is smarter to spend a few hours, diagnosing leak, than replacing parts. Remove some parts, if you cannot see leak.
Title: Re: Oil leak
Post by: TheBoy on 23 February 2013, 16:27:50
I've tried the cleaning and waiting for it to reappear, unsuccessfully so far.  I have a feeling its pooling somewhere, and the first bit of spirited driving, it just appears everywhere.

DLK and I were convinced it was coming from the upper sump to block seal, so we resealled all of that last summer.
Title: Re: Oil leak
Post by: TheBoy on 23 February 2013, 16:28:57
Oil pressure sensor did have a weep at one point, but washer replaced, and thats oil tight.
Title: Re: Oil leak
Post by: symes on 23 February 2013, 17:46:01
when cam seals leak it runs behind cover onto sump=dont dismiss those seals-I did mate TBH reckon those things are the fault IMHO :y
Title: Re: Oil leak
Post by: VXL V6 on 23 February 2013, 18:01:51
when cam seals leak it runs behind cover onto sump=dont dismiss those seals-I did mate TBH reckon those things are the fault IMHO :y
Virtually always the seals on the exhaust cams that fail. No idea why.
Title: Re: Oil leak
Post by: symes on 23 February 2013, 18:06:22
when cam seals leak it runs behind cover onto sump=dont dismiss those seals-I did mate TBH reckon those things are the fault IMHO :y
Virtually always the seals on the exhaust cams that fail. No idea why.
Me too :o weird :o
Title: Re: Oil leak
Post by: Abiton on 23 February 2013, 18:11:01
when cam seals leak it runs behind cover onto sump=dont dismiss those seals-I did mate TBH reckon those things are the fault IMHO :y
Virtually always the seals on the exhaust cams that fail. No idea why.
Me too :o weird :o

Exhaust valves get much hotter than inlet valves; conduct their heat into lifters, lifters conduct heat into cam lobes, cams run hotter and perish rubber seals faster?

Just an idea.  :-\  Bit far fetched maybe?
Title: Re: Oil leak
Post by: feeutfo on 23 February 2013, 22:15:17
Not pass fluid then, given the dash oil warnings...?

What was the outcome of dip stick?

Could remove cam covers and belt to check its not running down?


Happy to fiddle from Thursday on. :)
Title: Re: Oil leak
Post by: feeutfo on 23 February 2013, 22:15:36
Not pass fluid then, given the dash oil warnings...?

What was the outcome of dip stick?

Could remove cam covers and belt to check its not running down?


Happy to fiddle from Thursday on. :)

With the car obviously. ::)
Title: Re: Oil leak
Post by: Andy B on 23 February 2013, 22:26:00
My oil leak was a rear crank shaft oil seal ........... I paid someone to do it.  ;)
Title: Re: Oil leak
Post by: tidla on 23 February 2013, 22:27:37
Live with it. Everyone else does. rather cars.

cam covers, cam seals, oil cooler seals, bridge seals.

Gona by that "Christine car" people talk about that fixes itself by the morning.
Title: Re: Oil leak
Post by: car5car on 24 February 2013, 01:37:54
when cam seals leak it runs behind cover onto sump=dont dismiss those seals-I did mate TBH reckon those things are the fault IMHO :y
Virtually always the seals on the exhaust cams that fail. No idea why.
they are lower and oil is there.
Title: Re: Oil leak
Post by: Nick W on 24 February 2013, 07:41:19
I'm with Tidla, just live with it. It's far too late to complain to Vauxhall about engines that seem to have oil leaks carefully designed in. Every Omega I've seen has had a filthy engine.
Title: Re: Oil leak
Post by: TheBoy on 24 February 2013, 10:47:35
when cam seals leak it runs behind cover onto sump=dont dismiss those seals-I did mate TBH reckon those things are the fault IMHO :y
As said, these are fine - or were when checked last year. They were specifically checked due to the oil leak.
Title: Re: Oil leak
Post by: TheBoy on 24 February 2013, 10:52:28
Not pass fluid then, given the dash oil warnings...?
Engine oil - it was black until Christmas, as I hadn't changed the oil  :-[, now its clearish

What was the outcome of dip stick?
Failed to get it out. Gave up after losing the B-Bolt, and tunnie's socket

Could remove cam covers and belt to check its not running down?
Did that last year, it was clear.


This leak has been going on a while, which is why I changed the cam cover gaskets at Guffer's bash.
Title: Re: Oil leak
Post by: TheBoy on 09 August 2013, 16:18:54
In the last couple of weeks, the amount of oil the car is using has increased dramtically.  This is noticible in the amount if drops on the floor after a run, though this may be skewed by the fact I don't have a funnel to poor fresh oil in, and the filler tube was in the garage...


Currently using about half a litre every 3 days/250 miles.

Given what had been previously checked, I'm still thinking the bottom of the dipstick tube?  I failed to get the dipstick tube out last time, and ran out of time on the day.

Does it need o rings, or just use sealer?  I did buy o rings, but they are now lost with everything else.


I had hoped this would last til Newent, where I could get someone who owns tools to take pity on my misfortunes, and locate/fix the leak, but I'm not sure it will last that long.
Title: Re: Oil leak
Post by: tunnie on 09 August 2013, 16:28:26
Worth smearing some sealant around the base of the dipstick by hand?  :-\
Title: Re: Oil leak
Post by: chrisgixer on 09 August 2013, 16:32:09
If its leaking that much it would be easier to spot hopefully.

Can you run it down to your local mot man and run the engine at 3k rpm while its on a ramp or lift? Set the cruise control or something to keep the revs up..?

Or if it will make it down here..?
Title: Re: Oil leak
Post by: tunnie on 09 August 2013, 16:33:40
Oh I'm back in Brackley next weekend, so if you need a hand? Can pop it around, we can get it up in the air see whats going on?   :y
Title: Re: Oil leak
Post by: aaronjb on 09 August 2013, 16:40:57
Or if it will make it down here..?

Or here if you want to borrow a pit.
Title: Re: Oil leak
Post by: jb on 09 August 2013, 17:39:23
Very likely to be oil pump to block seal - a big job that most avoid but at your Elle of loss you may not have much option.
Title: Re: Oil leak
Post by: dbdb on 09 August 2013, 18:12:25
if you're really desperate (which you probably are 6 months on) you can get flourescent dye  http://www.ebay.co.uk/itm/111134316409  (http://www.ebay.co.uk/itm/111134316409)- add it to the oil and go around with a UV light.  It will show you the new leaking oil where before you would just see oil everywhere.  Obviously change the oil shortly afterwards, maybe twice, the dye is really aimed at diesel oil I suspect.   

You can get UV torches on ebay for couple of quid, search for 'UV flashlight' and tick the 'worldwide' box.
Title: Re: Oil leak
Post by: Gaffers on 09 August 2013, 19:27:49
The cylinder head gaskets never leak oil..................

It's not as rare as you might think.  The very first HG replacement I did on a car was pissing oil out the side of the head through the HG.  Started off slowly and got progressively worse.

On the Omega the fire rings are solid and the entire HG can disintegrate around them.  Not saying that this is the cause of the leak but I would just not write it off
Title: Re: Oil leak
Post by: tunnie on 09 August 2013, 19:31:37
The cylinder head gaskets never leak oil..................

It's not as rare as you might think.  The very first HG replacement I did on a car was pissing oil out the side of the head through the HG.  Started off slowly and got progressively worse.

On the Omega the fire rings are solid and the entire HG can disintegrate around them.  Not saying that this is the cause of the leak but I would just not write it off

Recall the bullet having a full top end rebuild at approx 180 maybe 160k?  :-\
Title: Re: Oil leak
Post by: dbug on 09 August 2013, 21:06:06
Sure the cam covers aren't warped Jaime - Big Al finally solved the oil leak on the Elite he bought off me by replacing the cam covers ;)
Title: Re: Oil leak
Post by: TheBoy on 09 August 2013, 21:28:56
The cylinder head gaskets never leak oil..................

It's not as rare as you might think.  The very first HG replacement I did on a car was pissing oil out the side of the head through the HG.  Started off slowly and got progressively worse.

On the Omega the fire rings are solid and the entire HG can disintegrate around them.  Not saying that this is the cause of the leak but I would just not write it off

Recall the bullet having a full top end rebuild at approx 180 maybe 160k?  :-\
135k, give or take, due to HGF on the passenger bank. Usual 1998 3.0l failure.
Title: Re: Oil leak
Post by: TheBoy on 09 August 2013, 21:31:56
Very likely to be oil pump to block seal - a big job that most avoid but at your Elle of loss you may not have much option.
Where does that look to leak from?

After cleaning up, although difficult to pinpoint, appears to come the top of the sump, A/C compressor side. Its possible its coming from down the upper sump to block seal, but DLK and I resealed that last year.
Title: Re: Oil leak
Post by: TheBoy on 09 August 2013, 21:33:26
Oh I'm back in Brackley next weekend, so if you need a hand? Can pop it around, we can get it up in the air see whats going on?   :y
Terbs meet next weekend.

Actually, hmmm, yes, Wycombe. Anyone taking jack and stands?
Title: Re: Oil leak
Post by: symes on 09 August 2013, 21:36:54
Oh I'm back in Brackley next weekend, so if you need a hand? Can pop it around, we can get it up in the air see whats going on?   :y
Terbs meet next weekend.

Actually, hmmm, yes, Wycombe. Anyone taking jack and stands?
yes mate-and some tools :y :y pm if anything else :y
Title: Re: Oil leak
Post by: blue_dream on 11 August 2013, 01:03:40
Hi mate
          You and me both then, my bloody mig is doing the same, oil appearing on the front lip to the sump pan, have changed the crankshaft oil seal, next is to change the oil level switch seal, cannot be cam cover seals as this would be burning on the manifolds  :( mine as only started doing this after an oil change, using 10w 40 same oil as before, i've had all the front apart to check and its clean, im deciding to clean down one more time and if i cannot pin point the leak i will put some sort of addtive in stop the mess :( :(
Title: Re: Oil leak
Post by: TheBoy on 11 August 2013, 09:46:36
Hi mate
          You and me both then, my bloody mig is doing the same, oil appearing on the front lip to the sump pan, have changed the crankshaft oil seal, next is to change the oil level switch seal, cannot be cam cover seals as this would be burning on the manifolds  :( mine as only started doing this after an oil change, using 10w 40 same oil as before, i've had all the front apart to check and its clean, im deciding to clean down one more time and if i cannot pin point the leak i will put some sort of addtive in stop the mess :( :(
I believe mine is coming from the AC compressor side of the block, so haven't changed the oil level switch seal.
Title: Re: Oil leak
Post by: sjc on 11 August 2013, 12:35:25
Watching with interest - mine has the very same symptoms.

Long story, but I changed the engine recently and cleaned the new engine before I put it in, plus fitted new cam cover seals because I knew they were leaking, also took the precaution of doing the rear crank seal because I was changing the flywheel anyway.

So I also get oil pooling on top of the sump and have changed the oil pressure switch and seal but it made no difference.

If I clean it up, then it sometimes goes for a few days with no new oil but if I take it for a thrash then the oil appears.  Top end is all dry as a bone, poked some kitchen roll behind the cam cover with a ruler and left it there for a few days - came out dry so it's not the cam seals.

Next step is to wrap some kitchen roll round the oil level sensor for a few days and see if it's coming from there.

May also try running it with the timing cover off to see if that helps to spot it.

I will find it eventually!
Title: Re: Oil leak
Post by: TheBoy on 16 August 2013, 20:08:25
I'm not convinced these o rings that the dealer provided are correct :(

Anyone taking a suitable sealant?
Title: Re: Oil leak
Post by: chrisgixer on 17 August 2013, 08:18:34
Cam over goo?
Title: Re: Oil leak
Post by: TheBoy on 17 August 2013, 09:15:43
Cam over goo?
Before my garage blew up, I would have tried Silkaflex, but its not fireproof, so I guess cam cover sealant is next best thing. Got any?
Title: Re: Oil leak
Post by: chrisgixer on 17 August 2013, 09:46:25
Yep. :y
Title: Re: Oil leak
Post by: 05omegav6 on 17 August 2013, 10:26:43
Will pop some sikaflex in the box as well, just in case :y
Title: Re: Oil leak
Post by: chrisgixer on 17 August 2013, 20:44:58
How long does it take NOT to remove the dip stick tube.


(Not the dip stick, but the tube the dip stick sits in, just to be overly clear)

Poxy thing. ::)
Title: Re: Oil leak
Post by: Big_Al on 17 August 2013, 20:48:15
How long does it take NOT to remove the dip stick tube.


(Not the dip stick, but the tube the dip stick sits in, just to be overly clear)

Poxy thing. ::)


Bad day then Mr. G . . . .  :-\     any progress at all on the leak ? :-\
Title: Re: Oil leak
Post by: TheBoy on 18 August 2013, 09:22:16
How long does it take NOT to remove the dip stick tube.


(Not the dip stick, but the tube the dip stick sits in, just to be overly clear)

Poxy thing. ::)
3 grown men about 5 hours, as a guess :P
Title: Re: Oil leak
Post by: TheBoy on 19 August 2013, 13:10:29
Well, apparently the oil level warning is back on the display, so guessing its no better or no worse than before.

Given the amount of yanking, I guess the dipstick to block seal is fine.

What next?


Given that jb and Taxi Al have both suggested oil pump, is this likely?  Given I have zero tools or anywhere to work, is this doable in a field near Newent?
Title: Re: Oil leak
Post by: Kevin Wood on 19 August 2013, 15:17:14
IIRC it's due a cam belt anyway?

I would suggest removing the cam belt, then pulleys and backplate. That should give you enough visibility of the oil pump to block interface to decide if it's leaking. I suspect the oil pump is sealed to the block with a gasket, so that might be all you need to cure it. Maybe someone with an engine out of the car could comment on what else might need to be removed to get at the oil pump? Crank pulley needs to come off, so the correct tools required there. Maybe the upper sump would have to be dropped? :-\

I assume that the feed from the oil pump goes straight to the oil filter. That means it must pass down an oil gallery in the passenger side of the block, so the output of the pump must pass into the block in that region. That's backed up by the location of the relief valve on the pump, so yes, a possibility that it'd leak there, I'd say.

I had a troublesome coolant leak a couple of years back. It kept emerging forwards from that little channel in the top of the sump pan, just to the passenger side of the block. In the end it was the water pump seal, so leaks from the front do seem to be able to track back down the block and emerge there as if they come from further back. :-\
Title: Re: Oil leak
Post by: TheBoy on 19 August 2013, 18:16:28
OK, sounds like a plan.  Anyone bringing a V6 cam lock kit to Newent? Its way overdue anyway  ::)
Title: Re: Oil leak
Post by: Entwood on 19 August 2013, 18:18:02
OK, sounds like a plan.  Anyone bringing a V6 cam lock kit to Newent? Its way overdue anyway  ::)

If I can get mine back from Joff I'll bring it along for you  :)
Title: Re: Oil leak
Post by: Gaffers on 19 August 2013, 19:55:48
OK, sounds like a plan.  Anyone bringing a V6 cam lock kit to Newent? Its way overdue anyway  ::)

I'll bring mine :y

But someone else can do the work, I cant risk it so close to the race ;)
Title: Re: Oil leak
Post by: 05omegav6 on 19 August 2013, 22:08:13
IIRC it's due a cam belt anyway?

I would suggest removing the cam belt, then pulleys and backplate. That should give you enough visibility of the oil pump to block interface to decide if it's leaking. I suspect the oil pump is sealed to the block with a gasket, so that might be all you need to cure it. Maybe someone with an engine out of the car could comment on what else might need to be removed to get at the oil pump? Crank pulley needs to come off, so the correct tools required there. Maybe the upper sump would have to be dropped? :-\

I assume that the feed from the oil pump goes straight to the oil filter. That means it must pass down an oil gallery in the passenger side of the block, so the output of the pump must pass into the block in that region. That's backed up by the location of the relief valve on the pump, so yes, a possibility that it'd leak there, I'd say.

I had a troublesome coolant leak a couple of years back. It kept emerging forwards from that little channel in the top of the sump pan, just to the passenger side of the block. In the end it was the water pump seal, so leaks from the front do seem to be able to track back down the block and emerge there as if they come from further back. :-\

No need :y have to remove the sump retaining bolts from either side of the crank, (and obviously the other oil pump bolts), should pull forward straight off the crank, no need to remove the crank seal either :y

Only three key points are...

1. Wind the crank splines with tape prior to removing the pump.
2. Be sure to clean and reseal the Oil Pump to Sump mating surfaces carefully and thoroughly.
3. Pay attention to the specific Oil Pump to Block gasket, as they vary, and be sure to apply sealant to the gasket where specified. Between the Book of Blocks and TIS, that should be plain enough.

Don't forget Tea either :y
Title: Re: Oil leak
Post by: Entwood on 20 August 2013, 20:49:49
Joff has kindly returned my Cam locking kit .. it will accompany me to Newent... if anyone wants to use it they will be welcome .. :)
Title: Re: Oil leak
Post by: VXL V6 on 20 August 2013, 20:54:40
I'll try and remember mine as well... And the 30mm spanner!