Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: amba on 07 July 2008, 20:14:36

Title: Cool running
Post by: amba on 07 July 2008, 20:14:36
Since last Friday the temeprature gauge has been reading very low.Prior to issues temp would always reach mid point within about 5 mins driving and would never go above slightly over mid way or slightly below mid way.
Now after 20 mins driving needle only just goes above 87 and when stood in traffic with air con off to stop extra cooling only just reaches 90.
Whilst I know this may be great as far as not over heating is concerned can any body suggest what has gone wrong and how to fix it?The gauge does work and the car is not loosing water.Thanks
Title: Re: Cool running
Post by: markey mark on 07 July 2008, 20:16:06
i would start with thermostat bud  :y
Title: Re: Cool running
Post by: amba on 07 July 2008, 20:22:46
But wouldn,t the thermosat have open after an hour on the motorway or sitting in London rush hour traffic,even in this weather??
Title: Re: Cool running
Post by: Big_Mart on 07 July 2008, 20:23:53
Agree with mark sounds like thermostat.
Title: Re: Cool running
Post by: Big_Mart on 07 July 2008, 20:26:22
Quote
But wouldn,t the thermosat have open after an hour on the motorway or sitting in London rush hour traffic,even in this weather??
the problem with the thermostat is its stuck open mate hence the reason why it takes a long time to heat up and cools down on the motorway or with the a/c on. :y
Title: Re: Cool running
Post by: amba on 07 July 2008, 20:30:20
Was hoping it wasn,t that.Think will drain down in morning and do full flush through just in case..thermostat does seem strange as engine feels up to temperature and no resistance in water pipes.Hoped it might just be a lazy gauge and would correct its self but been the same all day.Temp does move up slightly with A/C off so is registering a temperature.The thermostat replacement is not a job I would look forward to.
Title: Re: Cool running
Post by: amba on 07 July 2008, 20:32:08
Will it be a problem if left as is for the summer or should it be done sooner than later,as no worries about heat in car at moment?
Title: Re: Cool running
Post by: Mike Collins on 07 July 2008, 21:02:14
I've had this on two V6's, changing the thermostat is an instant cure. Well instantish, takes a while to do.

What was interesting is that there was no visible defect on the removed thermostats.

If it's not getting up to temperature, fuel consumption may suffer and condensation may not be evaporated from the oil. More frequent breather cleaning may be needed.
Title: Re: Cool running
Post by: amba on 07 July 2008, 21:34:10
Thanks guys. A side from slightly higher fuel usage will car be ok to use through summer months with stat open as have just spent ££££s recently and could do with rebuilding the Omega fund prior to costly stat replacement,as really don,t like the look of replacing it myself and think I can live without heat,although tried heater today and was as hot as always so am hoping coolant flush might do the trick.  
Title: Re: Cool running
Post by: amba on 07 July 2008, 22:42:00
Before I think about replacing the stat,would it be worth replacing the "coolant temperature sensor" as I have had the plenum ect on/off several times doing the cam cover seals,and unsure if these can become damaged.
For the cost of a sensor ?? might be a simpler fix than stat.
Title: Re: Cool running
Post by: Lazydocker on 07 July 2008, 23:02:08
I'm afraid you're just grasping at straws... There are classic symptoms of a failing thermostat and that is the only part that will cure the problem if replaced. You may mask the symptoms slightly with other action but you wont cure it!
Title: Re: Cool running
Post by: amba on 07 July 2008, 23:05:30
Thanks Lazydocker.Should listen to what I always say and cure the problem not the symptoms.
Looks like stat change in order,so better search for part numbers and see if I can find a write up on "how to ".
Title: Re: Cool running
Post by: Entwood on 07 July 2008, 23:28:01
Agreed ^^^   straw clutching at its best !!  :)

Seriously, a quick and easy thermostat test :

Open bonnet, start engine from cold, hold top hose of radiator, record feeling of heat.

If hose remains constantly cold then has a sudden noticeable "burst" of heat, then goes cold again, followed by another "burst" of heat then thermostat is working, it is now neccesary to find out at what temperature.

If hose temperature very slowly rises with no noticeable "bursts" then thermostat is stuck open.

HTH