Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: dave.h on 02 March 2020, 23:52:29

Title: 2.5 V6 Engine running cool
Post by: dave.h on 02 March 2020, 23:52:29
Hello - My 2.5V6, only just got it, seems to be running very cool.

When I collected it, I had to drive through city traffic and it seemed normal at 90 ish on the gauge.

When I got onto the motorway though, it cooled down to between 70 and 75, heat was coming through the cabin but not a lot.

My thought would be the thermostat needs changed but is there anything else that could need to be looked at?

Thanks in advance

David
Title: Re: 2.5 V6 Engine running cool
Post by: BazaJT on 03 March 2020, 08:09:24
Certainly sounds like a lazy thermostat,changing it would be my first port of call.How long does it take to get up to temperature?
Title: Re: 2.5 V6 Engine running cool
Post by: biggriffin on 03 March 2020, 11:02:10
Coolent temperature sensor.
Title: Re: 2.5 V6 Engine running cool
Post by: dave.h on 03 March 2020, 14:50:58
Thanks for the replies both.

It gets to temperature in what i'd expect is normal, but it soon cools down when the car starts moving at speed. When in town, it warms up in maybe 10 minutes.

I will also look at changing the temp sender at the same time.

I have "My Naff Code Reader" here and it hasn't raised any fault codes and the sensor voltage seems within tolerance, according to "My Naff Code Reader" at least!

I will order a thermostat and a sensor as can always send one back if it isn't needed, but genuinely, thanks for the advice.

Cheers

David
Title: Re: 2.5 V6 Engine running cool
Post by: amba on 03 March 2020, 15:26:17
If replacing the thermostat I would budget for a new transfer pipe and O rings as likelihood of separating thermostat housing is a lottery and safer having all bits to hand.

Good luck with the "B bolt" if you havent ventured into those depths before ...otherwise just lots of pulling apart to get to what should be a simpler part to replace
Title: Re: 2.5 V6 Engine running cool
Post by: Jan Suhr on 03 March 2020, 15:37:15
Well you should try to wiggle loose the transfer pipe before you unbolt the thermostat housing. It usually come off after a while. O-rings on it must be replaced. It also helps if you remove the engine lift loop that is taking up some space there.
Title: Re: 2.5 V6 Engine running cool
Post by: amba on 03 March 2020, 18:34:07
I found enlarging the hole in the lift bracket means the B Bolt is easier to position
Title: Re: 2.5 V6 Engine running cool
Post by: biggriffin on 04 March 2020, 13:49:55
Well you should try to wiggle loose the transfer pipe before you unbolt the thermostat housing. It usually come off after a while. O-rings on it must be replaced. It also helps if you remove the engine lift loop that is taking up some space there.


 This^^^^ along with a generous coating of wd40 (other brands) around the thermostat were transfer pipe goes in.
Title: Re: 2.5 V6 Engine running cool
Post by: Tick Tock on 05 March 2020, 11:44:10
I've got a lazy thermostat on my 2.5 CDX. It's been like this a while and only really gets up to temperature when driving around town and in slow traffic. Out on the open road it usually sits at around 75 to 80 degrees. It's been one of those jobs that I feel I really should do something about, but with the constant wet weather in the UK for the last 6 months or so, the time and inclination to do it are low on my list.

My heater provides a good flow of hot air when I need it, the average MPG is always around 28. Any thoughts on the detrimental effect on the engine in the long term? At 150k on the clock it still runs smoothly for a one-day-a-week driver.
Title: Re: 2.5 V6 Engine running cool
Post by: robson on 05 March 2020, 14:04:37
28MPG sounds good for a little used 2.5