Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: PaulW on 18 October 2007, 17:34:27

Title: Thermostat...
Post by: PaulW on 18 October 2007, 17:34:27
How easy are these to replace on the V6??

Can drive atleast 4 miles now and the temperature gauge is still barely above the bottom, yet after its stood for a while or gone for a bit further it starts coming upto about 92...  It just takes ages to get to any sort of temperature!
Title: Re: Thermostat...
Post by: Darth Loo-knee on 18 October 2007, 21:06:48
Quote
How easy are these to replace on the V6??

Can drive atleast 4 miles now and the temperature gauge is still barely above the bottom, yet after its stood for a while or gone for a bit further it starts coming upto about 92...  It just takes ages to get to any sort of temperature!


It has been rather cold the last few mornings so I wouldn't think that would help.. 92-95 is around normal running temp.....
but I thought that if your thermostat was not opening it would over heat, and if it was stuck open it would never get hot :-?

As for getting to it I am sure you have to get right down into the "V".....
Title: Re: Thermostat...
Post by: Kevin Wood on 18 October 2007, 21:21:18
Try starting it from cold and see if you can feel warm water in the top radiator hose. This should stay pretty much cold until the engine is up to running temperature and the tnermostat opens and then it will get very hot very quickly. If it warms up slowly with the engine it could be that the thermostat is not closing.

Kevin
Title: Re: Thermostat...
Post by: PaulW on 19 October 2007, 11:54:31
Quote
Try starting it from cold and see if you can feel warm water in the top radiator hose. This should stay pretty much cold until the engine is up to running temperature and the tnermostat opens and then it will get very hot very quickly. If it warms up slowly with the engine it could be that the thermostat is not closing.

Kevin

Just started it now, left it for about 10 mins checking all the time... the top hose was warming up very slowly during this time :(
Title: Re: Thermostat...
Post by: ians on 19 October 2007, 12:30:43
That's the same as mine - I think the stat is stuck open
Title: Re: Thermostat...
Post by: PaulW on 19 October 2007, 14:10:36
Did about 4 miles, checked hoses again - luke warm...  another 10 on top, and its just about reached 93 on the dash, hoses still only just warm and not hot as they should be...
Title: Re: Thermostat...
Post by: Paul M on 19 October 2007, 14:59:06
Quote
Quote
How easy are these to replace on the V6??

Can drive atleast 4 miles now and the temperature gauge is still barely above the bottom, yet after its stood for a while or gone for a bit further it starts coming upto about 92...  It just takes ages to get to any sort of temperature!


It has been rather cold the last few mornings so I wouldn't think that would help.. 92-95 is around normal running temp.....
but I thought that if your thermostat was not opening it would over heat, and if it was stuck open it would never get hot :-?

As for getting to it I am sure you have to get right down into the "V".....

It will still get up to 95 degrees or so when driving round town, especially if you have to stop lots or go into lower gears. If the temperature drops off the bottom of the scale soon after getting up to speed on a motorway cruise then it's a sure sign of a stuck open stat.

Bit of a pig to change, need to remove the plenum and inlet bridge, it's at the front of the valley so not that difficult in terms of access. However you have to remove a few bolts and maybe move a pipe, both of which are reputed to be a nightmare, and the housing will probably break in the process so you should get a replacement one too. There is an uprated housing available, but you'll need longer bolts.

I haven't done this job myself, this is the info I get from reading posts on here. Isn't there a how-to? Certainly the oil cooler change guide will help with a lot of what needs to be done.
Title: Re: Thermostat...
Post by: Mike Collins on 19 October 2007, 17:02:48
Yes it is a bit of a struggle, the thermostat comes complete with housing, not sure about seal.
 The hardest part I found was separating the transfer pipe from the thermostat housing. The first time I ended up breaking the transfer pipe. The second one I took a Dremel type grinder to the housing and cut a groove to allow the housing to split.

You will almost certainly need to have the two O rings, they will probably be damaged.

Your symptoms sound the same as my last one, the change cured it.
Title: Re: Thermostat...
Post by: PaulW on 20 October 2007, 00:26:57
Well just did another test (was bored)

100 miles of motorway driving... Temp barely even reached 90, it was just hovering above bottom...

Parked up in a service station, just idled and it went to 95...

Back on motorway, straight down again to just above bottom :(
Title: Re: Thermostat...
Post by: Entwood on 20 October 2007, 00:36:01
pound to a pinch of poo  ... thermostat failed in fully open position :(

and I can't see a "how-to" anywhere .. looks like Mr Haynes advice needed ... :(

Have found this .. can give more info if needed..

Quote
Thermostat, Replace

Note:  For warranty reasons, the thermostat is only supplied together with the thermostat housing.

  Remove

Remove coolant pipe – see operation "Coolant Pipe, Remove and Install". Remove intake bridge – see operation "Intake Bridge, Remove and Install". Remove fastening bolts (1) from cylinder block and remove thermostat housing with thermostat.

  Install

Install new thermostat housing with new seal ring (2) in cylinder block – 20 Nm / 15 lbf. ft. Install coolant pipe – see operation "Coolant Pipe, Remove and Install". Install intake bridge – see operation "Intake Bridge, Remove and Install".

Title: Re: Thermostat...
Post by: TheBoy on 20 October 2007, 09:56:08
Sounds stat to me.  Not easiest job on V6, but not impossible - ones plenum and inlets off, all becomes clear...