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MG MGF Technical - Rising water level

Water level rose about 20mm in header tank had problems before with air lock in cooling system to radiator and HGF so I now check levels every time I get in or out of car
Bled small amount of air from radiator level back to normal car running ok no cooling problems but where is air coming from and have I a problem starting to arise does anyone have any thoughts

Thanks John
popabear134@yahoo.co.uk

Hi ,
can be several different causes;
- Faulty expansion bottle cap. Cheap and easy fix,get a new one that works properly. (Itīs a "breather" type spring valve inside the cap that is known for leaking/malfunctioning.)When the cap works OK there is a considerably pressure in the system = rubber hoses expand and almost nothing seen from the slightly increased warm water-volume.

- "Farting" head gasket. Some gas leak from the firerings. More serious... As you had a HGF, was the head skimmed or at least checked for straightness?

- Sloppy bleeding from the start... Airpockets can be trapped for some time and suddelly release. Continue to keep an eye on the waterlevel and top up if needed.

BR, Carl.
Carl

thanks Carl cap seems ok as loads of pressure if after standing a long time head skimmed and checked
also oil and water clean so i hope it is like you say just trapped air moving to rad

thanks again john
Edward John Smith

John, it would probably be a good idea to properly bleed the cooling system again so that you are confident that no air remains in the coolant system. Then, if air re-materialises, you know that you have got a problem.

Carl's already listing mechanisms that 'air' could enter the cooling system, and I don't have much to add to that. But if you are worried about the condition of the fire-rings on the head gasket, an MoT exhaust gas analyser will give you a good clue: if hydrocarbons are detected in the expansion tank, then there is a very good chance that there is a problem with the gasket.

HTH
Rob Bell


Does it misfire when you first start the car?

Leave the car for a day or two.
When you start it again... if it misfires on one (wet) cylinder then it's very likely to be the firering as Carl suggests.

I know. It's just happened to me. :o(

P.

Paul Nothard

Have you had it confirmed Paul?
Rob Bell

Confirmed by the water in the cylinder. That's pretty good evidence, but the head is not off yet due to lack of time. :-(

I'll let you know what happens tho. :o)

P.
Paul Nothard

If you have water in the cyclinder, don't run the engine.

Water does not compress very well.
Because of this fact.......bad things happen.


Cheers,
Branko

Branko

cyclinder????


Doh!

Branko

By that I assume you mean sick-linder ?
Freud

This BBS should have a spell checker!!





Branko

This thread was discussed between 16/04/2005 and 19/04/2005

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