Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: venom on 20 May 2011, 23:37:13

Title: Higher Temp than normal
Post by: venom on 20 May 2011, 23:37:13
I've changed my header tank with a brand new VX one & changed the old blue antifreeze with the new orange VX coolant, it has always been fine sitting at around 90/95 even when it's sitting on tick over even if it's left for a long time, but it now goes to the 100 mark for a while but then drops to between 95/100 & does creep back up but only when driving but not on tick over & I'm not losing any water it's just at where it should be.
I've re flushed it added more coolant instead of some water so must be 70/30 mix at the mo, any clues  :question :(
Title: Re: Higher Temp than normal
Post by: blackviper90210 on 20 May 2011, 23:44:28
Mines the same. Sits around 95 then climbs to 100 fan kicks in and drops to 95... Hope it's normal too, lol.
Title: Re: Higher Temp than normal
Post by: Stallion on 21 May 2011, 00:12:38
Thats pretty much normal matey!  :y
Title: Re: Higher Temp than normal
Post by: blackviper90210 on 21 May 2011, 08:11:58
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Thats pretty much normal matey!  :y
Fair enough, can stop watching the gauge as much and enjoy the drive  :) :) :) :)
Title: Re: Higher Temp than normal
Post by: venom on 21 May 2011, 15:21:22
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Thats pretty much normal matey!  :y

My only concern was that untill I changed the tank & coolant it never got above the the mark before the 100 at any time  :exclamation
Title: Re: Higher Temp than normal
Post by: kcl on 21 May 2011, 15:23:57
Air in the system ? Sounds abit like an airlock...
Title: Re: Higher Temp than normal
Post by: venom on 21 May 2011, 15:31:23
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Air in the system ? Sounds abit like an airlock...

Thats what I think but I've all I can think of & followed the guide on here, so dont know :question
Title: Re: Higher Temp than normal
Post by: TheBoy on 21 May 2011, 21:43:58
I'd say airlock, as 100C is too high.

Title: Re: Higher Temp than normal
Post by: JasonH on 21 May 2011, 22:47:50
It might do that if the aircon is off or not working. When the air con is active two great big fans on the front of the radiator run and they really help keep the car temperature stable.

I had one fan fail and the fluctuation in engine temperature became noticable.
Title: Re: Higher Temp than normal
Post by: Stallion on 21 May 2011, 22:55:11
i advised normal, as mine does the same, sometimes it goes 95 comes down, sometimes touches 100 and comes down. if it was sticking on 100c then thats a worry??
Title: Re: Higher Temp than normal
Post by: venom on 22 May 2011, 17:36:06
This is really starting to do my @#$%ing nut in been out in the car today & the only way to keep the temp down to 95 is to have to heating on HI in the cabin, then it drops down to around 95/97 but put it in low & after 10 mins it creeps back up, but we pulled in to the motorway services & I cracked open the header cap just to release some pressure but there was hardly any if any at all  >:( so if the system isn't being pressurised would it get hot or no heat ad could it be my old cap
Title: Re: Higher Temp than normal
Post by: TheBoy on 22 May 2011, 19:37:36
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i advised normal, as mine does the same, sometimes it goes 95 comes down, sometimes touches 100 and comes down. if it was sticking on 100c then thats a worry??
Only in very extreme circumstances should it get close to 100C on gauge.


Quoting any of the 'mine runs at 95C' is pointless without stating what the midpoint temp on gauge is, as that varies on Omegas ;)
Title: Re: Higher Temp than normal
Post by: TheBoy on 22 May 2011, 19:38:22
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This is really starting to do my @#$%ing nut in been out in the car today & the only way to keep the temp down to 95 is to have to heating on HI in the cabin, then it drops down to around 95/97 but put it in low & after 10 mins it creeps back up, but we pulled in to the motorway services & I cracked open the header cap just to release some pressure but there was hardly any if any at all  >:( so if the system isn't being pressurised would it get hot or no heat ad could it be my old cap
Do you get near brackley, so we can see what the 2 temp sensors read?
Title: Re: Higher Temp than normal
Post by: venom on 22 May 2011, 19:53:25
No but its just up the road so I can do cheers mate
Title: Re: Higher Temp than normal
Post by: Abiton on 22 May 2011, 20:53:50
Try draining some of your 70:30 mix and topping up with just water.  Coolant isn't as good at heat transference as water, so you want the right mix.

I wonder if your water pump isn't pumping as well as it once did?  Do you know when it was last changed?

You say orange coolant was used.  I've only ever heard about recent Vx coolant being red/pink.  :-/
Title: Re: Higher Temp than normal
Post by: Brikhead on 22 May 2011, 22:05:32
My first thought was an airlock but after reading through I'd check all the fans are working correctly and also re-fill with the correct grade of Vx. coolant.

Might be an idea to take TheBoy up on his kind offer to check the actual temperature readings compared with what the gauge is displaying.

Glad you made it back home safe, btw! :y
Title: Re: Higher Temp than normal
Post by: venom on 22 May 2011, 23:01:27
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Try draining some of your 70:30 mix and topping up with just water.  Coolant isn't as good at heat transference as water, so you want the right mix.

I wonder if your water pump isn't pumping as well as it once did?  Do you know when it was last changed?

You say orange coolant was used.  I've only ever heard about recent Vx coolant being red/pink.  :-/

It started off as 50/50 but then the problem started so when I was trying the bleed the system instead of adding more water to replace what I lost and watering it down I added more coolant, but before I change it I'll wait and see what the temp sensors show first  :y
The water pump was changed about 15000 miles ago when I did the cambelt and was a GM one.
The coolant is the VX one when its in the can it looks orange but when it's in the header it looks pinkish  :-/ 
Title: Re: Higher Temp than normal
Post by: venom on 22 May 2011, 23:05:57
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My first thought was an airlock but after reading through I'd check all the fans are working correctly and also re-fill with the correct grade of Vx. coolant.

Might be an idea to take TheBoy up on his kind offer to check the actual temperature readings compared with what the gauge is displaying.

Glad you made it back home safe, btw! :y

Yes mate I'm going to take TheBoy up on the offer  :y
Cheers got home fine hot but fine  ;D
If you do take the wings off let me know and I'll pop up in a couple of weeks and buy them mate  :y
Title: Re: Higher Temp than normal
Post by: venom on 24 May 2011, 13:21:30
Well started from scratch again today drained the system refilled with a new 50/50 mix & burped it for at least an hour to make sure if the was an airlock I'd get it out, so fingers crossed :-?
Title: Re: Higher Temp than normal
Post by: venom on 25 May 2011, 08:07:06
Right still no joy, so has anyone changed the water temp sensors because I'm wondering if the fan isn't cutting in at the second speed.
If I cant sort this this will be one more Mig to the big scrap yard in the sky  :'(
Title: Re: Higher Temp than normal
Post by: Gaffers on 25 May 2011, 10:31:12
Possible knackered thermostat?

I had similar symptomns with mine and found it was stuck open.  As your system is not pressurising I wonder if yours is stuck closed?
Title: Re: Higher Temp than normal
Post by: Kevin Wood on 25 May 2011, 11:38:10
Let's try to establish some facts about the problem.

Does the engine run hot when sitting in traffic or when on a run (40 MPH +), or both?

If it's got hot does a period of cruising at speed bring the temperature down again?

If you leave it idling at full working temperature for a few miuntes do both radiator hoses get piping hot? Do the fans come on periodically to control the coolant temperature? (try this with climate off, so the air con fans aren't running).

At speed, there is more than enough airflow through the radiator to keep the engine cool, so that takes the fans out of the equation and we are looking at a fault in the coolant circuit itself (thermostat, water pump, blocked radiator, airlock). If that lot is working but it gets hot in traffic, the fans and associated relays and thermoswitches come under scrutiny.

Gauges are not always accurate, as has been said. If the fans are coming on and off to control the temperature and it doesn't overheat on a run then all is well, IMHO.

Kevin
Title: Re: Higher Temp than normal
Post by: venom on 25 May 2011, 13:12:20
Quote
Let's try to establish some facts about the problem.

Does the engine run hot when sitting in traffic or when on a run (40 MPH +), or both?

If it's got hot does a period of cruising at speed bring the temperature down again?

If you leave it idling at full working temperature for a few miuntes do both radiator hoses get piping hot? Do the fans come on periodically to control the coolant temperature? (try this with climate off, so the air con fans aren't running).

At speed, there is more than enough airflow through the radiator to keep the engine cool, so that takes the fans out of the equation and we are looking at a fault in the coolant circuit itself (thermostat, water pump, blocked radiator, airlock). If that lot is working but it gets hot in traffic, the fans and associated relays and thermoswitches come under scrutiny.

Gauges are not always accurate, as has been said. If the fans are coming on and off to control the temperature and it doesn't overheat on a run then all is well, IMHO.

Kevin

Cheers Kevin

Does the engine run hot when sitting in traffic or when on a run (40 MPH +), or both?

After I've flushed or tried to bleed the system & it's on tickover it keeps at normal running temp, yesterday it sat for 1.5 hours running at normal with no probs  :-/, later we had to run down to Surrey to pick up my daughter & after 20 mins of driving it went up to just below 100  >:( put the heater on it comes down.

If it's got hot does a period of cruising at speed bring the temperature down again?

No just driving doesn't bring it down

If you leave it idling at full working temperature for a few miuntes do both radiator hoses get piping hot? Do the fans come on periodically to control the coolant temperature?

Well when on tickover yes but have not checked them after a run as didnt think of checking when we get in as I thought if they did on tickover they would be both hot  :-[ & yes the fan kicks in at around the 90 & middle mark & can hear it kick in when driving & the same temp, but as to whether it steps up to the 2nd speed I dont know :question
Title: Re: Higher Temp than normal
Post by: Andy B on 25 May 2011, 13:19:19
I wonder if your radiator is partially blocked ie there's enough flow though it while it's idling, but under load it can't get enough flow through it to disipate the heat.  :-/
My car never had any overheating problems until we stuck a caravan on the back & towed up a long hill near home. The temp got higher & higher - I didn't realise there was a high temp red warning light  ::) - until we levelled out. A new radiator cured it, even towing in the heat of France (33o/34o) the last couple of years.
Title: Re: Higher Temp than normal
Post by: Kevin Wood on 25 May 2011, 13:25:27
Quote

Does the engine run hot when sitting in traffic or when on a run (40 MPH +), or both?

After I've flushed or tried to bleed the system & it's on tickover it keeps at normal running temp, yesterday it sat for 1.5 hours running at normal with no probs  :-/, later we had to run down to Surrey to pick up my daughter & after 20 mins of driving it went up to just below 100  >:( put the heater on it comes down.

If it's got hot does a period of cruising at speed bring the temperature down again?

No just driving doesn't bring it down

If you leave it idling at full working temperature for a few miuntes do both radiator hoses get piping hot? Do the fans come on periodically to control the coolant temperature?

Well when on tickover yes...

Sounds to me like the radiator might be partially blocked perhaps? Possibly thermostat not opening fully, although they normally fail open. :-/

Maybe worth taking the rad. out and giving it a thorough flush with Fernox / dishwasher powder or something, and blow the core clear of insects with an airline?

It doesn't sound fan related to me. Worth a look with the Tech 2 just to make sure the temperature is being indicated correctly though.

Kevin
Title: Re: Higher Temp than normal
Post by: venom on 26 May 2011, 06:52:16
Quote
Quote
Let's try to establish some facts about the problem.

Does the engine run hot when sitting in traffic or when on a run (40 MPH +), or both?

If it's got hot does a period of cruising at speed bring the temperature down again?

If you leave it idling at full working temperature for a few miuntes do both radiator hoses get piping hot? Do the fans come on periodically to control the coolant temperature? (try this with climate off, so the air con fans aren't running).

At speed, there is more than enough airflow through the radiator to keep the engine cool, so that takes the fans out of the equation and we are looking at a fault in the coolant circuit itself (thermostat, water pump, blocked radiator, airlock). If that lot is working but it gets hot in traffic, the fans and associated relays and thermoswitches come under scrutiny.

Gauges are not always accurate, as has been said. If the fans are coming on and off to control the temperature and it doesn't overheat on a run then all is well, IMHO.

Kevin

Cheers Kevin

Does the engine run hot when sitting in traffic or when on a run (40 MPH +), or both?

After I've flushed or tried to bleed the system & it's on tickover it keeps at normal running temp, yesterday it sat for 1.5 hours running at normal with no probs  :-/, later we had to run down to Surrey to pick up my daughter & after 20 mins of driving it went up to just below 100  >:( put the heater on it comes down.

If it's got hot does a period of cruising at speed bring the temperature down again?

No just driving doesn't bring it down

If you leave it idling at full working temperature for a few miuntes do both radiator hoses get piping hot? Do the fans come on periodically to control the coolant temperature?

Well when on tickover yes but have not checked them after a run as didnt think of checking when we get in as I thought if they did on tickover they would be both hot  :-[ & yes the fan kicks in at around the 90 & middle mark & can hear it kick in when driving & the same temp, but as to whether it steps up to the 2nd speed I dont know :question

The mrs came home last night after a good 2 hour drive & she had the heat on HI & fan speed on 1 & the temp stayed down to just over the half way mark & checked the top & bottom hoses were red hot & quite hard  :-/