Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Paulus on 11 August 2008, 09:50:02

Title: Petrol smell in Coolant
Post by: Paulus on 11 August 2008, 09:50:02
I have been having a problem with coolant dissapearing somewhere. There are no external leaks, but I have to top of the tank every 100-200 miles or-so.

Yesterday, when topping it up, I got a strong smell of petrol from the expansion tank when I took the cap off. Is that something hinting at impending doom or could it be nice and simple (like me)?
Title: Re: Petrol smell in Coolant
Post by: TheBoy on 11 August 2008, 10:31:21
Quote
I have been having a problem with coolant dissapearing somewhere. There are no external leaks, but I have to top of the tank every 100-200 miles or-so.

Yesterday, when topping it up, I got a strong smell of petrol from the expansion tank when I took the cap off. Is that something hinting at impending doom or could it be nice and simple (like me)?
Is performance down? If firerings let go, normally a lack of performance is noticible.
Title: Re: Petrol smell in Coolant
Post by: Paulus on 11 August 2008, 10:37:31
There's no noticable reduction in performance...it still hauls ass. It's been losing water for a couple of months now. It's not got any worse, there's no noticable smoke on acceleration and on the whole, it runs really well (I'd like to think that this is down to the 5K oil changes). I averaged 38mpg when crusing home from Chester yesterday at 60mph.

It's really worrying me now as I am going on holiday in a couple of weeks...driving to Lands End.
Title: Re: Petrol smell in Coolant
Post by: philhoward on 11 August 2008, 10:38:07
Start the car from cold with the expansion cap off..Look for a trickle of bubbles (like you get from a glass of coke/etc).  Bubbles = bad, alas...
Might not start bubbling straight from cold..so leave it for a couple of minutes.

Gush of bubbles = really bad...empties the header tank if you rev the engine (like i had on a BMW 318is i was trying to diagnose) = really, really bad!  ON that BMW, it only had compression on 2 cylinders, though...

A gasket to coolant leak doesn't always manifest itself in a loss of performance - water injection!
Title: Re: Petrol smell in Coolant
Post by: Paulus on 11 August 2008, 11:35:35
Oh good. So it could be the head gasket then...

I will have to test the bubbles thing at lunch time. I'll look forward to it. I know that it doesn't gush out, but as you say, there may be small bubbles.  :'(
Title: Re: Petrol smell in Coolant
Post by: philhoward on 11 August 2008, 12:08:07
As you've probably read from on here, HG issues are very rare on V6's - water loss is usually HBV/coolant bridge.

Just out of interest - does it retain pressure in the header tank overnight/standing?  BTW, it should do...
Title: Re: Petrol smell in Coolant
Post by: Paulus on 11 August 2008, 12:36:58
Quote
As you've probably read from on here, HG issues are very rare on V6's - water loss is usually HBV/coolant bridge.

Just out of interest - does it retain pressure in the header tank overnight/standing?  BTW, it should do...

Now that's a very good question. IIRC it does, but I will confirm tomorrow morning when it has had a rest.

I know that the HBV isn't leaking. I have only recently replaced it (in the hope that it was leaking). It made no difference. As for the coolant bridge, how and where do I check that?
Title: Re: Petrol smell in Coolant
Post by: philhoward on 11 August 2008, 13:05:21
I'll have to throw in the towel here, as i don't have a V6......but i gather most of the "prime suspects" are much easier to get at/see with the plenum off...awaiting help from a V6 guru (like JamesV6CDX)..
Title: Re: Petrol smell in Coolant
Post by: Paulus on 11 August 2008, 14:02:55
Well you've done a grand job so far.

COME ON JAMESV6CDX (or similar)!!!!  ;)
Title: Re: Petrol smell in Coolant
Post by: TheBoy on 11 August 2008, 14:59:24
Usual places for v6 coolant leaks:

HBV (behind 1/3/5 bank)
Water pump seal (front of engine)
Stat housing (in the valley)
Oil Cooler plate (in valley)
coolant bridge dowty washers (in the valley)
Radiator
Transfer pipe (rear of engine)
If the hoses have gone soft, any of them, particularly one from HBV to coolant bridge
back of 2/4/6 block on 1998 3.0l, HG.
Title: Re: Petrol smell in Coolant
Post by: Paulus on 11 August 2008, 15:44:33
Thanks for the help guys. I'll have to wait till the weekend as I work away from home...currently in Swindon designing Pay-and-Display machines (don't hate me)...and I haven't got any tools here.
Title: Re: Petrol smell in Coolant
Post by: Andy B on 11 August 2008, 18:28:46
It must be in the air. My car has decided to join in losing coolant. :( I noticed it was a little low last week after we got back from a weekend up in a field near Grassington - about 50 miles away - so I topped it up. I used the car today for the first time since then, and the 'low coolant' message came up. I'm about 1" below the mark but as in other cases, no obvious signs of loss.
If any one sees a black Omega, fastened to a caravan, with the bonnet up on the hard shoulder heading south on Saturday morning .... it'll be me! :o  :y
I just have a feeling it's my water pump as I think I saw the odd bit of water 'spitting' up towards the bagpipes at the front. Oh well! Ce la vie!  ;)
Title: Re: Petrol smell in Coolant
Post by: markey mark on 11 August 2008, 18:46:21
dont leave water pump mate if it fails you will be in the $hit  ::)
Title: Re: Petrol smell in Coolant
Post by: Andy B on 11 August 2008, 18:54:49
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dont leave water pump mate if it fails you will be in the $hit  ::)

I know!  ;) I shall be under the bonnet in the morning - weather permitting - looking for where my water is escaping. A failed water pump is the last thing I want while we're so far away from home with a caravan and with no recovery  :-?
Title: Re: Petrol smell in Coolant
Post by: Andy B on 12 August 2008, 10:34:39
Can't find anything obvious, but with the bonnet up & the engine running I was very aware of the 'fan belt' tensioner bearing being as dry as a witches .... . With the belt removed to remove the roller (seal popped off & a little grease added) I can feel some play in the pump.
I eventually managed to order another pump from the dealers - had to go down there in the end  >:( - so I'll start stripping it down.  :(
Title: Re: Petrol smell in Coolant
Post by: markey mark on 12 August 2008, 10:39:55
Quote
Can't find anything obvious, but with the bonnet up & the engine running I was very aware of the 'fan belt' tensioner bearing being as dry as a witches .... . With the belt removed to remove the roller (seal popped off & a little grease added) I can feel some play in the pump.
I eventually managed to order another pump from the dealers - had to go down there in the end  >:( - so I'll start stripping it down.  :(


be best to change it andy mate  :y
Title: Re: Petrol smell in Coolant
Post by: Andy B on 12 August 2008, 12:54:56
Quote
....

be best to change it andy mate  :y

The new pump is in a box next to me, unfortunately I've run out of time before I go to work.
The old pump is definately beyond its best, play in the bearing, & there's some evidence of pink antifreeze underneath. Fingers crossed that this is the only place I'm losing water from. :-?
Title: Re: Petrol smell in Coolant
Post by: sassanach on 12 August 2008, 13:23:04
if you can smell petrol in the coolant then sooner or later you are going to have to bite the bullet  and change those head gaskets.
Title: Re: Petrol smell in Coolant
Post by: Paulus on 17 August 2008, 13:56:24
In between rain showers, I checked the compression on the engine. Here's what I got.

1. 185 PSI
2. 185 PSI
3. 185 PSI
4. 185 PSI
5. 165 PSI
6. 185 PSI

I repeated the test twice to confirm.

What's that sound like?
Title: Re: Petrol smell in Coolant
Post by: Paulus on 18 August 2008, 09:02:25
Quote
In between rain showers, I checked the compression on the engine. Here's what I got.

1. 185 PSI
2. 185 PSI
3. 185 PSI
4. 185 PSI
5. 165 PSI
6. 185 PSI

I repeated the test twice to confirm.

What's that sound like?

Anybody?  :'(
Title: Re: Petrol smell in Coolant
Post by: TheBoy on 18 August 2008, 09:04:44
Thats about 1.5bar down...  ....not massive, but I guess could be failing.  If you smell fumes in header tank though, thats fairly conclusive...
Title: Re: Petrol smell in Coolant
Post by: Paulus on 18 August 2008, 18:05:27
Well it'll have to wait a few weeks (hopefully). I'm off to Cornwall at the weekend.