Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Seth on 16 May 2008, 10:28:47

Title: 2.5TD RUNNING TEMPERATURE
Post by: Seth on 16 May 2008, 10:28:47
Hi all,
I've just used our 2.5TD Estate fro towing our caravan for the first time.
Performance generally was pretty satisfactory, except that the temperature went just above 100 degrees on motorway inclines. Once you cleared the summit, it quickly returned to it's usual temperature - around 95 degrees.
I note that the 'red' on the gauge is just past 110 degrees, so not much room for error!
Does anyone know if this occurrence is normal, has anyone, (especially caravanners), experienced/cured this?
Thanks chaps!
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Omegatoy on 16 May 2008, 12:05:47
its reasonably normal mate, main fans dont come on tilll it hits 100 degrees, first fans come on at 95 if your switches are working? although does it hit the hundred mark only after puling hard for a while or straight away??
Omegatoy
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Seth on 16 May 2008, 12:23:45
Thanks for replying.
It hits the 100 mark after about a mile or so of pulling hard.
You say the main fans - are these the two that are down towards the base of the radiator?
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: osealy on 16 May 2008, 17:39:51
Mines the same, rather worrying. Temp drops about 3 degrees if I turn Climate onto HI. Apparently shitty water pumps & silted rads dont help.
I couldn't undo the viscous Fan, thats as far as I've got.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: MickAP on 16 May 2008, 18:07:37
Quote
Mines the same, rather worrying. Temp drops about 3 degrees if I turn Climate onto HI. Apparently naffty water pumps & silted rads dont help.
I couldn't undo the viscous Fan, thats as far as I've got.

You may already know this but it is a LH thread.

Mick
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Omegatoy on 16 May 2008, 20:26:10
Quote
Thanks for replying.
It hits the 100 mark after about a mile or so of pulling hard.
You say the main fans - are these the two that are down towards the base of the radiator?

yep they switch onto low speed at about 95 and high speed operation at 100, you can hear them running when they do so you would know if they were not running hence the reason for the question about how long before it starts to go over the 100, slightly silted/blocked rad is
most likely cause of your hot running,
Omegatoy
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 16 May 2008, 20:41:42
Admittedly mine has an A1 cooling system now (and no viscous fan).  It had no troubles towing an Omega Estate (heavier than most vans), even on hills, never went above 96C on gauge.  Admittedly, never went faster than 60 mph either.

100C on gauge is actually nearer 110C in reality, which is the safe limit of the engine.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Seth on 17 May 2008, 10:39:23
Right then, do you think that I should try flushing the rad as a starting point?
My idea would be to use a flushing additive in the system for a few days driving - what do you think?
I'll add that there's always a 50-50 antifreeze content in my TD.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 17 May 2008, 11:33:11
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Right then, do you think that I should try flushing the rad as a starting point?
My idea would be to use a flushing additive in the system for a few days driving - what do you think?
I'll add that there's always a 50-50 antifreeze content in my TD.
Worth checking the waterpump has a full compliment of vanes left on it.

If rad is partially silted, or has blockages, replacement is only option. And they ain't cheap :(

As to flushing, I found the Forte one to be the most effective, and I followed instructions.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: philhoward on 17 May 2008, 11:37:24
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Worth checking the waterpump has a full compliment of vanes left on it.

Not sure if the same applies to the diesel as the petrol, but the BMW petrol 6-pots of the same era are known for losing waterpump vanes on a regular basis.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 17 May 2008, 11:38:17
Quote
Quote
Worth checking the waterpump has a full compliment of vanes left on it.

Not sure if the same applies to the diesel as the petrol, but the BMW petrol 6-pots of the same era are known for losing waterpump vanes on a regular basis.
Yup, their crap diesels are equally poorly designed....
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Seth on 17 May 2008, 12:33:55
Thanks again fellas,
I should be able to get hold of the Forte stuff - we've a stockist locally.
Regarding the water pump - mine's brand new - and will be changed every two years. The actual flow of the coolant is now superb!
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 17 May 2008, 15:36:00
Quote
Thanks again fellas,
I should be able to get hold of the Forte stuff - we've a stockist locally.
Regarding the water pump - mine's brand new - and will be changed every two years. The actual flow of the coolant is now superb!
In that case, might be worth removing rad and giving it a seperate flush.  I used a load on bleach in my one one.  Also, can lay flat, and pour boiling water in, and see if there are any 'cold spots' (blockages).
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: osealy on 17 May 2008, 17:22:30
If I take the rad out do I have to disconnect the tranny cooler.
My climate pump is RIP so thats not a prob?
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 17 May 2008, 19:38:23
Quote
If I take the rad out do I have to disconnect the tranny cooler.
My climate pump is RIP so thats not a prob?
yes.  won't lose much atf from it, but you'll need to redo levels afterwards
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Omegatoy on 17 May 2008, 20:04:46
OOOH BIG CLUE THERE!!!!! shagged/worn auto transmission can make the engine get really hot!!! thats what happened to me  when i melted the autobox the engine temp went skyhigh!!!
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Seth on 27 May 2008, 10:33:59
Right, I've checked - the rad fans did not cut in.
Anyone know where the thermal switch for these fans is located?
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: andyiow on 27 May 2008, 16:23:25
Highest I have seen on my manual TD is about 92/93 and that was when I was going up a longish and fairly steep hill in 2nd for about 15minutes or so fully loaded and a trailer.

I have noticed that the temperature also has a habit of going up and staying warmer when the oil is nearing changing time. Have yet to actually have any of the fans on, but do check and clear the fan areas every month or so to clear any debris out such as leaves and the occasional small bird.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: platty on 27 May 2008, 16:30:08
My TD always sits around 90 degrees with the viscous fan on. During the winter I take the viscous off and it still stays about the same, when you welly it it make 95 absolute maximum as the fans come straight on then.

Its worth removing the viscous to check that the electric fans come on when they should - with the viscous on they never get a chance!!

Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 27 May 2008, 21:34:12
Quote
Right, I've checked - the rad fans did not cut in.
Anyone know where the thermal switch for these fans is located?
2 of them, top and bottom of rad, passenger side (non A/C models on have 1 switch).
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 27 May 2008, 21:36:00
Temp wise, mine has a good cooling system, and it sits just below 93/95, creeping up to 96 sometimes before electric fans do the business.

I run without a viscous fan.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Seth on 16 June 2008, 21:02:13
I've now changed the rad.
It's made hardly any difference, although the old rad was considerably heavier than the new one. I've temporarily wired-up the two electric rad fans to run constantly - again, little difference.
What d'you think, should I try a new thermostat?
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 16 June 2008, 21:07:20
Have you checked waterpump still has a full compliment of vanes?
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: osealy on 16 June 2008, 21:31:49
I see this with interest. I think he said earlier that he had a new pump.
I can manage fine mostly. but in heavy traffic or on long inclines I have to turn the heating on to keep it below 100.
However I hope to tow 1200Kg skiboat 120mls for hols & dont want to have to do it at night.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Omegatoy on 16 June 2008, 21:37:40
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I see this with interest. I think he said earlier that he had a new pump.
I can manage fine mostly. but in heavy traffic or on long inclines I have to turn the heating on to keep it below 100.
However I hope to tow 1200Kg skiboat 120mls for hols & dont want to have to do it at night.

well out here the day temp is around 31/32 and we come up some long hard steep inclines and my temp never gets above 98 even when really revving engine to beat the spaniard boy racers up the hills, :o even towing the big caravan up the hills it doesent get over 99 and that weighs around 2 ton!!
so something is really wrong somewhere!!!
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 16 June 2008, 21:39:56
I have my theories about the oil, but want to ensure the cooling system is A1 before going down that line
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Omegatoy on 16 June 2008, 21:41:45
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I have my theories about the oil, but want to ensure the cooling system is A1 before going down that line


hehe you had a good teacher!!!! :y
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 16 June 2008, 21:44:22
Quote
Quote
I have my theories about the oil, but want to ensure the cooling system is A1 before going down that line


hehe you had a good teacher!!!! :y
It cured mine. Shame head was already shafted :(
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: osealy on 16 June 2008, 21:45:02
My electric fans come on occaisionally. vicous i think is coasting, Faulty temp sender??? Can I use the Lidl oven meat prod to check like I did on small block boat eng which was reading double the truth, I stuck it through a cork stuck in the sender hole. replaced sender so guess guage is faulty, (boat that is)
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 16 June 2008, 21:47:56
Quote
My electric fans come on occaisionally. vicous i think is coasting, Faulty temp sender??? Can I use the Lidl oven meat prod to check like I did on small block boat eng which was reading double the truth, I stuck it through a cork stuck in the sender hole. replaced sender so guess guage is faulty, (boat that is)
Could be faulty temp sender, though TD ones normally good.  If a 1998 onwards, could also be a config error on instrument panel.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: Seth on 16 June 2008, 22:19:37
Thanks so far for replies chaps!
I'll change the thermostat tomorrow, and I'll let you all know what happens.
Incidentally, regarding prices of parts:
QH water pump - £38, QH thermostat - £10, Valeo rad - £156, all these include VAT. Vx quoted £270 for rad - other quotes for rad were as high as £330 inc.
Good value here in South Wales - if you deal with the right guy!
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: osealy on 16 June 2008, 22:21:37
97 P reg , will run all day at 120kph but if it's a hot afternoon and a long incline heads towards the red.
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: platty on 17 June 2008, 09:24:53
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QH thermostat - £10

I've got a new genuine one here (inc. rubber seal)  for £20 delivered if you are interested!!
Title: Re: 2.5TD RUNNING TEMPERATURE
Post by: TheBoy on 17 June 2008, 20:02:39
Just to give you some idea, I've floored mine - foot right on the boards - for several minutes at a time, and never gone above 96C. Got it up to 97C going up Hardknot pass a few months ago - 4 up and a bit of lugguage.

I gave it some large today, then had to come to a screaming halt, but still, got to 96C whilst sat in traffic, never higher....