Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: amba on 29 April 2010, 09:58:59

Title: Strange coolant leak
Post by: amba on 29 April 2010, 09:58:59

If I top up the coolant reservoir when cold to guide level marks on side after about 100/150 miles coolant has dropped down to about an inch lower than start point.
If I top it up the same happens again and coolant leak is noticeable around bottom of gearbox(have replaced HBV so fairly sure that is not problem)
What is really strange and the point of my question is...if I don,t top up coolant level it never goes below the 1 inch lower point and I don,t see any leaks from below.
There is no cracks in the coolant reservoir and the pressure cap is new and seal intact.
It almost seems like it has enough coolant in so gets rid of the excess...but levels don,t point to that.
Coolant low warning has never appeared.
Any possible conclusions .

Title: Re: Strange coolant leak
Post by: Kevin Wood on 29 April 2010, 10:19:27

I am guessing that, with the larger air gap in the top of the expansion tank, the system is not pressurising as much, so the leak stops. If a leak's been observed there's something amiss though.

Might be worth making up an expansion tank cap with a schraeder valve fitted so you can pressurise it manually (to about 1 bar) and check for leaks when the system is cold with the plenum removed.

Kevin

Title: Re: Strange coolant leak
Post by: Zuffenhausen on 29 April 2010, 10:38:36

Heres a guide for how to do the pressure test.

http://www.omegaowners.com/forum/YaBB.pl?num=1225142864

Title: Re: Strange coolant leak
Post by: amba on 29 April 2010, 12:17:25

Thanks guys...will get on the case at some point,though as doesn,t seem to be a major issue at moment(last fatefull words !!)

Title: Re: Strange coolant leak
Post by: Zuffenhausen on 29 April 2010, 16:34:02

Last summer ours had a split in the underside of the top hose that opened up when pressurised untill the fluid level dropped enough to reduce the pressure. Much the same as yours seems to be doing.

Title: Re: Strange coolant leak
Post by: manny on 29 April 2010, 19:09:02

I had same problem with coolant dripping off the two bolts on bottom of gear box. Turned out it was leaking from thermostat and running between the cylinder heads and down back of engine . If you take plenum off and look in the area of thermo and oil cooler you should see where the leak is.

Title: Re: Strange coolant leak
Post by: markfree on 29 April 2010, 19:38:01

Quote

I had same problem with coolant dripping off the two bolts on bottom of gear box. Turned out it was leaking from thermostat and running between the cylinder heads and down back of engine . If you take plenum off and look in the area of thermo and oil cooler you should see where the leak is.

Easier to take the bag-pipes off and shine a torch into the V (or stick your fingers in  :-?) and you should see/feel if either your oil-cooler/thermo housing is leaking. :y

Title: Re: Strange coolant leak
Post by: andyc on 30 April 2010, 09:08:42

mine turned out to be the n/s head gasket :'(

Andy