Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: lou on 13 November 2009, 00:29:18

Title: Cleaning of oil breather box
Post by: lou on 13 November 2009, 00:29:18
As I have become paranoid about the breathing system I would like to find out when a suitable drill size is used on the small pipe (with small hole) on the metal box whether the drill should go right through or just a little way. I am sure the last time I cleaned it, it did not go in very far.
Title: Re: Cleaning of oil breather box
Post by: duggs on 13 November 2009, 07:39:32
Fear not my friend...You are NOT alone.
I too am also paronoid about EXACTLY the same thing.

I use an opened up paper clip and wiggle it around in said hole !!!!
Title: Re: Cleaning of oil breather box
Post by: Marks DTM Calib on 13 November 2009, 10:27:26
It goes in a fair long way.......
Title: Re: Cleaning of oil breather box
Post by: Andy H on 13 November 2009, 11:45:59
(http://images.omegaowners.com/images/guides/BreatherBodyV6/VaderPictures014.jpg)

When I first got my last v6 it had done 130,000 miles (allegedly). I had the cylinder heads off when a head gasket failed and so took the breather box off the engine to inspect it. It was totally caked up inside. I got about a cup full of hard black rubbish out of it before giving up and buying a new one from VX.

Poking a paperclip in the top would have been a complete waste of time. If I had managed to shift all the crud it would have fallen into the sump (& possibly blocked the oil strainer......).

If you are concerned (and you should be) find a way of removing it from the engine to clean it.
Title: Re: Cleaning of oil breather box
Post by: Gaffers on 13 November 2009, 12:46:24
Is it possible to take it off without removing the head?
Title: Re: Cleaning of oil breather box
Post by: Andy H on 13 November 2009, 13:02:02
Quote
Is it possible to take it off without removing the head?
It is held on by four 6mm bolts. I already had my engine out and on an engine stand so I didn't look to closely at what might be in the way with the engine in the car.

(http://homepages.nildram.co.uk/~aholter/DSCF0804.jpg)
Title: Re: Cleaning of oil breather box
Post by: Gaffers on 13 November 2009, 13:04:56
Quote
Quote
Is it possible to take it off without removing the head?
It is held on by four 6mm bolts. I already had my engine out and on an engine stand so I didn't look to closely at what might be in the way with the engine in the car.

(http://homepages.nildram.co.uk/~aholter/DSCF0804.jpg)


Great pic, looks doable although fiddly :y
Title: Re: Cleaning of oil breather box
Post by: lou on 13 November 2009, 16:33:25
Ok, thanks for the advice. I will try papar clip first.....
Title: Re: Cleaning of oil breather box (update)
Post by: lou on 15 November 2009, 15:43:06
Just used paper clip in hole so to speak and it was well blocked after a little bit of pushing and wiggling I could push it throughall the way. My question is would that have done any lasting damage being blocked?
Title: Re: Cleaning of oil breather box (update)
Post by: PhilRich on 15 November 2009, 16:57:17
Quote
Just used paper clip in hole so to speak and it was well blocked after a little bit of pushing and wiggling I could push it throughall the way. My question is would that have done any lasting damage being blocked?


Lou, I think Andy H has just answered your querie. If the box is gunged up, then pushing a paperclip in isn't going to do any good at all by the sound of it? :-/
Title: Re: Cleaning of oil breather box
Post by: Andy H on 15 November 2009, 17:05:08
The Omega has plastic cam covers. If pressure builds up, due to blocked breathers, the pressure causes the gaskets to start weeping oil.

Once they have started leaking the cam cover gaskets don't seem to stop until new gaskets are fitted. A nuisance but not the end of the world.

I have heard that Vectra V6's have aluminium cam covers. Because they can take more pressure before flexing the crankshaft seals start leaking first. To replace the crankshaft seals you need to remove the flywheel and the oil pump which is quite a harsh penalty for not keeping the breathers clean...
Title: Re: Cleaning of oil breather box (update)
Post by: Andy H on 15 November 2009, 17:19:58
Quote
Quote
Just used paper clip in hole so to speak and it was well blocked after a little bit of pushing and wiggling I could push it throughall the way. My question is would that have done any lasting damage being blocked?


Lou, I think Andy H has just answered your querie. If the box is gunged up, then pushing a paperclip in isn't going to do any good at all by the sound of it? :-/
It is a shame that the breather box is so hidden away. I have just bought myself a replacement Omega with 116,000 miles on the clock. I should follow my own advice and clean the breather box right now but I haven't done it yet ::)

I think the Omega is typical in having two breather pipes.

The little one is connected to a small port on the throttle body, after the throttle butterflies, which sucks a small quantity of crankcase fumes out of the crankcase at tick over.

The larger one is connected to two larger ports on the throttle body, before the butterflies. This one isn't subjected to any suction at tick over (but will be at full throttle). It is the big one that is really important because this is where the bulk of fumes due to blow by past the piston rings will escape from the crankcase.

The gunge in the small pipe is an indicator of how blocked up the breather box is. Without taking it off you can't really tell whether the flow up the big pipe is restricted.
Title: Re: Cleaning of oil breather box
Post by: lou on 15 November 2009, 17:26:51
Just checked again and all pipes and ecotec are clear, held hand on top of oil filler at idle and reving it and it feels like a slight sucking definitely no pressure even after a run. Yet it still weeps from the bottom of the filler neck at times.I have tried two (old "O" rings). Idle and running are very smooth. Could the leak just be that it does not seal properly and perhaps I can use some silicone sealant?
Title: Re: Cleaning of oil breather box
Post by: Andy H on 15 November 2009, 17:36:03
Quote
Could the leak just be that it does not seal properly and perhaps I can use some silicone sealant?
Has your filler neck got the two ears on (like the ones on the filler cap) that engage with the hole in the cam cover?
Title: Re: Cleaning of oil breather box
Post by: feeutfo on 15 November 2009, 17:51:54
The filler neck is removeable. just lift the tab off the torx nut and twist. Cap can then be screwed in in its place. Might seal better. I guess next thing to try would be a new O ring.
Title: Re: Cleaning of oil breather box
Post by: lou on 15 November 2009, 17:52:13
yes i think so...just twist and turn