Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Spearmint on 01 August 2009, 18:51:00

Title: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 01 August 2009, 18:51:00
I changed what I perceived to be the fan switch when I removed / flushed out / refitted the rad which was the 2 pin switch that sits under the big fat hose on the passenger side of the rad.

I did the old boiling water test on the switch where the resistance didn't even drop down to below 150 Mega Ohms.

The fans still won't switch on though I know they work as I zapped them with 12v hence they spun into life.

So either I changed the wrong item or there is another switch in the system?

Any help as always is much appreciated.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: unlucky alf on 01 August 2009, 19:28:20
im the same as you & thought there was only the one fan switch, when you gave the fan 12v did you do it by bridging the two wires to that switch? i was wondering if perhaps there is a bad wire somewhere on that circuit, im also wondering if they are relay switched, i would start by shorting out the switch wires & go from there :y
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 01 August 2009, 21:23:30
yeah, chuck a paperclip in the plug wiring to prove wiring/relays/fuses
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 02 August 2009, 08:46:09
I fogot to note that I did find 12v at the plug though I didn't do any line to line checks so looks like that is next.

It make sense though with just chucking a paperclip in there. I hate trying to work out electrical gremlins with no diagrams!
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 02 August 2009, 19:02:50
Just done the check as noted above. The fans did not activate but I did hear a relay clicking over.

What else is in the circuit?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 02 August 2009, 19:10:34
Quote
Just done the check as noted above. The fans did not activate but I did hear a relay clicking over.

What else is in the circuit?
Big green (30A?) fuses near relay.

BTW, the Haynes book of 'dangle berries' does have the TD wiring diagrams in, even though it doesn't cover the engine mechanically
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 02 August 2009, 22:51:36
Cheers Theboy, looks like I had better get my ass down to Halfrauds then. :)
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 02 August 2009, 23:13:45
Quote
Cheers Theboy, looks like I had better get my ass down to Halfrauds then. :)
egay for haynes, halfrauds too expensive (unless you have trade card)
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 03 August 2009, 19:41:32
Yup, trade carded up satis though I shouldn't really have one! :D
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 03 August 2009, 19:46:59
Anyways, it was the 30amp fuse. Replaced that and the fans come to life.

The car is still running too hot for my liking. 95'c but then it just sort of hovers around that mark.

So that's:

A flushed out Rad / block etc.
A new Water Pump.
A new Thermostat.
A new Rad Fan Switch.
50/50 mix Coolant.
No leaks.
No Mayo.
Big fat pipe does become firm when the temps are that high but you can still press it.

I am at a loss. Any suggestions other than a can of petrol and a match?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: charlie on 03 August 2009, 20:45:25
dont do anything about this, i was going though the tis today looking for something else, when i found a update or mod , about 2.5td autos with air con getting to hot, something to do with the airflow though the grill.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Ghost on 03 August 2009, 20:55:27
If you look from the front ( or Back ) is your rad clean? ( ie bad airflow / cooling )
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 03 August 2009, 21:46:52
Looked ok when I had it out for flushing etc. Cleaned all the dead leaves and gunk from it anyway.

So what was this update then? I don't fancy ripping the air con rad out as that would be a little OTT.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 03 August 2009, 21:52:14
Maybe chop away all that plastic trim at the front?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 03 August 2009, 22:04:54
if it runs at the midpoint on gauge (95c for prefacelifts), then that is fine. Perfect in fact.  As long as it doesn't go anywhere near 100c
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Seth on 03 August 2009, 22:10:35
Quote
Anyways, it was the 30amp fuse. Replaced that and the fans come to life.

The car is still running too hot for my liking. 95'c but then it just sort of hovers around that mark.

So that's:

A flushed out Rad / block etc.
A new Water Pump.
A new Thermostat.
A new Rad Fan Switch.
50/50 mix Coolant.
No leaks.
No Mayo.
Big fat pipe does become firm when the temps are that high but you can still press it.

I am at a loss. Any suggestions other than a can of petrol and a match?
Mine behaves similarly, though normal running is around the 92 mark.
Show it a climb however, and it'll quickly rise to the 100 mark, especially with the caravan in tow. Once over the climb, then the temp will quickly settle down to 92 degrees again, and I fitted a brand-new rad too! Both fans running make little or no difference, and my own opinion is that the rad is simply not man enough for the job on 2.5TDs.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 03 August 2009, 22:18:46
Sethsmate - do you have viscous one, and undertray?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 04 August 2009, 20:05:01
Theboy, would you recommend ditching the undertray?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 04 August 2009, 20:40:30
Quote
Theboy, would you recommend ditching the undertray?
For the past couple of months, I've been racking my brains as to why my tractor always stayed at midpoint, no matter how hard it was driven. Never got it above 96/97 on gauge, despite thrashing the nuts off it up and down mountain passes.

It did have a very well maintained cooling system, but others here have as well.  Mine ran without the viscous, without the dowling around the viscous, and with no undertray.

Maybe someone with a good tractor (ie sethsmate, as he has new rad on his) could try removing these, and seeing what happens?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Omegatoy on 04 August 2009, 21:39:58
mine has no undertray and at around 40 degree in spain, it runs lovely at 90ish, full bore up a long hill with i.c fan on it rises to around 95/96
as sson as i hit the top and back off it comes right back down to normal hope that helps !!
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Seth on 04 August 2009, 22:01:20
Quote
Quote
Theboy, would you recommend ditching the undertray?
For the past couple of months, I've been racking my brains as to why my tractor always stayed at midpoint, no matter how hard it was driven. Never got it above 96/97 on gauge, despite thrashing the nuts off it up and down mountain passes.

It did have a very well maintained cooling system, but others here have as well.  Mine ran without the viscous, without the dowling around the viscous, and with no undertray.

Maybe someone with a good tractor (ie sethsmate, as he has new rad on his) could try removing these, and seeing what happens?

Right J, mine's still got the viscous fitted, (though I've yet to hear it 'kick-in'), the undertray's been removed, and there's no cowl around the viscous.

Normal running is 92 on the gauge, but'll rise to the 100 mark on climbs especially with the caravan in tow. Once over the climb, it'll quickly revert to 92 again. Trusted friends in the trade suggest that this is normal. They quickly point out that as the system is pressurized, then as long as the needle doesn't get to the red (110), which it doesn't, then there's nothing to worry about. Whilst I don't disagree, 100 is still a little close for comfort for my liking.

All that said, I'm planning on removing the 'stat and water pump, and back-flushing the block via the block drain plug. I'm thinking that there could be a restriction somewhere within, such as bits of the effing water pump impeller - what say you ...... ?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 05 August 2009, 06:21:52
Right, that's next on my list when I can be arsed. Ripping out the undertray.

Skyline doesn't have one and it's running temps are phenomenal but then it does have a much larger sump / rad / oil cooler than normal for trackwork etc.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: platty on 05 August 2009, 11:53:57
Quote
Right J, mine's still got the viscous fitted, (though I've yet to hear it 'kick-in'), the undertray's been removed, and there's no cowl around the viscous.
The viscous doesn't kick in does it? It turns constantly with the engine as far as I am aware.  :-/ (sapping power and making noise along the way)

I don't run a viscous, but still have the cowl and under tray in place and I cannot get the gauge to go above 96/97 no matter how hard I try.

Never done anything to the cooling system except replace the 'stat about 6 months ago because it was running too cool.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 05 August 2009, 18:08:23
Quote
Quote
Right J, mine's still got the viscous fitted, (though I've yet to hear it 'kick-in'), the undertray's been removed, and there's no cowl around the viscous.
The viscous doesn't kick in does it? It turns constantly with the engine as far as I am aware.  :-/ (sapping power and making noise along the way)

I don't run a viscous, but still have the cowl and under tray in place and I cannot get the gauge to go above 96/97 no matter how hard I try.

Never done anything to the cooling system except replace the 'stat about 6 months ago because it was running too cool.
If your viscous runs all the time and 'roars' even when cold, its breaked.  Yes, viscous fans will always turn, but they 'lock up' when hot.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 09 August 2009, 22:22:22
Well, the car is still pushing its luck with me WRT this snag.

I have had some suggestions of others experiences on other marques with the same snag.

Rad cap? OR Viscous Fan just isn't drawing enough air through?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 10 August 2009, 08:54:28
Both suggestions are ill conceived.

If it was rap cap, it would blow its load as soon as it warmed up.  Presumably its not leaking.

The TD is absolutely fine without viscous.  Its simply not needed in this country.  No small fan can drag in as much air as a car does at 70mph.



Reasons these engine overheat is mostly down to poor maintenence:

Don't go wasting your time and money down other avenues...
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 10 August 2009, 09:18:19
Now it's mentioned it is due an oil change, last time it was done at about 111K and the car is now sat at 114.5K.

So lots of flush and new oil then.

Hopefully, next time I update this thread it'll be to say the snag has cleared. Cheers Theboy.  :y
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 10 August 2009, 13:42:13
Quote
Now it's mentioned it is due an oil change, last time it was done at about 111K and the car is now sat at 114.5K.

So lots of flush and new oil then.

Hopefully, next time I update this thread it'll be to say the snag has cleared. Cheers Theboy.  :y
You'll need some pretty strong oil flush to clear away the sludge ('black death' it seems to be known as in BMW/Range Rover forums).  Omegatoy got me some a while back, would strip skin from your bones ;D
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: DJ Pete on 10 August 2009, 14:43:46
Quote
Quote
Now it's mentioned it is due an oil change, last time it was done at about 111K and the car is now sat at 114.5K.

So lots of flush and new oil then.

Hopefully, next time I update this thread it'll be to say the snag has cleared. Cheers Theboy.  :y
You'll need some pretty strong oil flush to clear away the sludge ('black death' it seems to be known as in BMW/Range Rover forums).  Omegatoy got me some a while back, would strip skin from your bones ;D

What flush should we be using then?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 10 August 2009, 19:24:22
Quote
Quote
Quote
Now it's mentioned it is due an oil change, last time it was done at about 111K and the car is now sat at 114.5K.

So lots of flush and new oil then.

Hopefully, next time I update this thread it'll be to say the snag has cleared. Cheers Theboy.  :y
You'll need some pretty strong oil flush to clear away the sludge ('black death' it seems to be known as in BMW/Range Rover forums).  Omegatoy got me some a while back, would strip skin from your bones ;D

What flush should we be using then?
Can't remember name, but it was stuff you ran at idle for 15-20mins, then immediately drained.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Seth on 10 August 2009, 20:58:13
Quote
mine has no undertray and at around 40 degree in spain, it runs lovely at 90ish, full bore up a long hill with i.c fan on it rises to around 95/96
as sson as i hit the top and back off it comes right back down to normal hope that helps !!

Hang on a min here ........
I've not been aware of my intercooler fan working - will this cause my temp to rise to 100 on long climbs?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: platty on 11 August 2009, 13:41:07
Quote
Quote
mine has no undertray and at around 40 degree in spain, it runs lovely at 90ish, full bore up a long hill with i.c fan on it rises to around 95/96
as sson as i hit the top and back off it comes right back down to normal hope that helps !!

Hang on a min here ........
I've not been aware of my intercooler fan working - will this cause my temp to rise to 100 on long climbs?
Not sure if it will make a huge difference or not...

I removed mine about a year ago because it was seized solid and collecting muck and sh&t which was impeding the flow somewhat. I planned to un-seize it and refit it via a switch. Needless to say this has not happened as yet  :-[
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 11 August 2009, 20:14:13
Quote
Quote
mine has no undertray and at around 40 degree in spain, it runs lovely at 90ish, full bore up a long hill with i.c fan on it rises to around 95/96
as sson as i hit the top and back off it comes right back down to normal hope that helps !!

Hang on a min here ........
I've not been aware of my intercooler fan working - will this cause my temp to rise to 100 on long climbs?
not much difference. Not all TDs have I/C fan either.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 11 August 2009, 20:15:58
Quote
Quote
Quote
mine has no undertray and at around 40 degree in spain, it runs lovely at 90ish, full bore up a long hill with i.c fan on it rises to around 95/96
as sson as i hit the top and back off it comes right back down to normal hope that helps !!

Hang on a min here ........
I've not been aware of my intercooler fan working - will this cause my temp to rise to 100 on long climbs?
Not sure if it will make a huge difference or not...

I removed mine about a year ago because it was seized solid and collecting muck and sh&t which was impeding the flow somewhat. I planned to un-seize it and refit it via a switch. Needless to say this has not happened as yet  :-[
Get it done.  It makes a noticibly (though not massive) difference :y


Oh yes, this is yet another reason to bin that gay viscous - it allows the leccy fans to come on a bit more (and thus i/c fan), which stops i/c fan seizing all the time
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 11 August 2009, 21:50:00
Ripped the undertray out tonight during an oil change which I couldn't complete as CAS decided to supply me with the wrong oil filter!  >:(

Anyways, once I have fresh oil in her, checked her over and hopefully eliminated my hot running issues I'll test out the removing viscous theory.

The only time these can serve a function really would be too draw air through at a standstill?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: platty on 12 August 2009, 08:51:54
Quote
Ripped the undertray out tonight during an oil change which I couldn't complete as CAS decided to supply me with the wrong oil filter!  >:(

Anyways, once I have fresh oil in her, checked her over and hopefully eliminated my hot running issues I'll test out the removing viscous theory.

The only time these can serve a function really would be too draw air through at a standstill?
The only time they serve any useful purpose is when they are in the bin!  ;D
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 12 August 2009, 20:16:14
Finished the oil change today and then took her for a short drive across town. Temp still reached 90'c but took alot longer to actually get there so I don't know if that is an encouraging result or not.

It'll get a good drive tomorrow so a good chance to check her then.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 12 August 2009, 20:17:29
Quote
Finished the oil change today and then took her for a short drive across town. Temp still reached 90'c but took alot longer to actually get there so I don't know if that is an encouraging result or not.

It'll get a good drive tomorrow so a good chance to check her then.
Did you use an oil flush?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 12 August 2009, 20:52:44
Yes, oil flush was used as well. Old oil wasn't anything exciting, no bits etc but obviously needed changing.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 12 August 2009, 21:28:13
Quote
Yes, oil flush was used as well. Old oil wasn't anything exciting, no bits etc but obviously needed changing.
Good luck :y
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 12 August 2009, 21:54:58
how high does the temp rise?
Its normal for it to rise up hills as the engine is under a lot more load. I tow a caravan and when going up long hills the temp goes right up just below the red but then drops when at the top. when driving solo it just rises slightly.
Have you tried removing the front grill and blowing the radiators out with compressed air?
I`m a hgv mechanic on bin wagons and we have to do this all the time due to dust and small debris that gets stuck in the radiator matrix. If we dont do it as soon as the truck looks at a hill the temp gauge goes into the red.
Hope this helps
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 12 August 2009, 22:31:35
Quote
how high does the temp rise?
Its normal for it to rise up hills as the engine is under a lot more load. I tow a caravan and when going up long hills the temp goes right up just below the red but then drops when at the top. when driving solo it just rises slightly.
Have you tried removing the front grill and blowing the radiators out with compressed air?
I`m a hgv mechanic on bin wagons and we have to do this all the time due to dust and small debris that gets stuck in the radiator matrix. If we dont do it as soon as the truck looks at a hill the temp gauge goes into the red.
Hope this helps
be aware, bmw's stated max 'safe' point is 110C, which is actually 100C on the omega temp gauge...
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 13 August 2009, 14:34:04
Temps still rise to the 95'c mark. It does take a little longer to get there but on my 20 mile run to work it eventually did so.

I suppose I could use an airline at work to blow through the 2 rads. Seems to be a little bit of grass collecting but nothing I would have imagined to cause such a drastic difference.

End of Feb 2009 it wouldn't budge past 80'c. I go abroad for 4 months where the car remained static and I come back to this overheating issue.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 13 August 2009, 19:04:09
TheBoy,
Am I right in thinking that the red on my gauge is 105 deg c?
In which case is BMW 110? Not too sure what you mean.
Thanks
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 13 August 2009, 19:35:17
Quote
TheBoy,
Am I right in thinking that the red on my gauge is 105 deg c?
In which case is BMW 110? Not too sure what you mean.
Thanks
the gauge on the omega ties severe porkies.

when gauge reads 100c, coolant is actually at 110c.

bmw state the m51tds engine is safe to 110c


bmw engines (all of them) tend to crack heads if they go beyond their safe range
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 13 August 2009, 19:41:04
Thanks for the advise.
Think I`ll try flushing mine out.
Is it not normal for them to go that high when towing a 1.3 ton caravan up a hill?
Mine has always done it thats all since I bought it 3 years ago. only tow about 3 times a year.
on normal everyday running the temp stays pretty much the same level
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 13 August 2009, 19:42:40
Quote
Thanks for the advise.
Think I`ll try flushing mine out.
Is it not normal for them to go that high when towing a 1.3 ton caravan up a hill?
Mine has always done it thats all since I bought it 3 years ago. only tow about 3 times a year.
on normal everyday running the temp stays pretty much the same level
no idea - i've never been daft enough to own a caravan ;D

certainly, i'd be very concerned above 100c on the gauge at any point
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 07 September 2009, 18:33:08
I still have this snag so when I got back from work I had a quick look under the bonnet. Now as it's running hot, after a journey, the electric fans are heard to kick in. So, looking under and through I noticed only one was operating. After the fans stopped (and with the engine off of course!) I had a quick poke about with my keys to find the drivers side electric fan is seized.

Could this be the cause of my running temps?

Is it a bumper off job to change?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 07 September 2009, 21:06:39
Quote
I still have this snag so when I got back from work I had a quick look under the bonnet. Now as it's running hot, after a journey, the electric fans are heard to kick in. So, looking under and through I noticed only one was operating. After the fans stopped (and with the engine off of course!) I had a quick poke about with my keys to find the drivers side electric fan is seized.

Could this be the cause of my running temps?

Is it a bumper off job to change?
Might not help.

If you can't free yours off, and you pass Brackley, think I have a spare TD one in garage.


As you can imagine, rad out, possibly a/c condenser as well (doubt you be able to make enough room to slide it out)
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Omegatoy on 07 September 2009, 22:14:47
??????????? fans are only sat there not bolted to rads, whip bumper off and they should fall out easily would have thought?
maybe wrong as i only had mine out when i was checking rad!!

the obvious and really only true way to determine what your cars running temp is, is to tech 2 it live data and see what the actual temp is cos the gauges just gordon brown you all the time!! :y
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 08 September 2009, 16:34:27
Are the gauges really that bad?
Do they usually read higher than the actual temp or lower?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 08 September 2009, 19:02:17
Quote
??????????? fans are only sat there not bolted to rads, whip bumper off and they should fall out easily would have thought?
maybe wrong as i only had mine out when i was checking rad!!

the obvious and really only true way to determine what your cars running temp is, is to tech 2 it live data and see what the actual temp is cos the gauges just gordon brown you all the time!! :y
Slam panel etc in way, they have to come out through engine bay
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 08 September 2009, 19:03:10
Quote
Are the gauges really that bad?
Do they usually read higher than the actual temp or lower?
The gauge reads high up until the lower marking, and low after midpoint.  The gauges are pretty consistent.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 11 September 2009, 07:48:35
So with my constant running temps of about 95'c it's actually running at 105'c-110'c?

So that said, surely it should have blown the HG or something by now?

Wheres the sender unit for the gauge? Think I'll try swapping that.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 11 September 2009, 09:16:03
Quote
So with my constant running temps of about 95'c it's actually running at 105'c-110'c?

So that said, surely it should have blown the HG or something by now?

Wheres the sender unit for the gauge? Think I'll try swapping that.

No. Just under 95, temp (ecu and instrument) will claim to be just under 90. Just over 95, and real temp will go up dramatically, reaching 110C by time gauge hits 100C.  Its at this point things are too hot.

Sender, if you want to change it (will do jack-all) is in head (intake needs to come off).  Both engine and dash senders mounted near each other and look same, but dash one only has 1 pin when you remove connector. Soz, can't remember which way round they are - about 75% certain front one is the dash one.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 11 September 2009, 11:44:52
Well if they'll not do anything there isn't any point in changing them. What about Tech 2 plugged into the Ecu to confirm if I'm being lied to or not by the gauge? How do I go about getting hold of one?

I can't see any more options really as I've changed pretty much everything in the system.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 14 September 2009, 20:14:56
Even though I cleaned out the rad to the best of my knowledge could it still be Fubar inside?

It's as if the rad is just not man enough to cope with cooling the coolant down so maybe a rad change would solve the snag?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 15 September 2009, 09:03:30
Is it better then to run the car with the viscous fan removed? even when towing?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 15 September 2009, 12:38:44
I've not been brave enough to try that out yet. I want a fully serviceable cooling system first. :D
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Pitchfork on 15 September 2009, 15:05:10
Quote
Is it better then to run the car with the viscous fan removed? even when towing?
It's certainly a lot quieter if the Viscous as failed & is locked up! :)
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 15 September 2009, 22:25:42
I`m the same. I just want a good cooling system.
I tow quite a bit and found my temp goes right up on hills then drops when on the flat.
I thought it was ok because it never actually went into the red but after TheBoy advised that the gauges lie, I`m a bit more weary now.
Though it has never been a problem in the past and the car has done a fair few miles towing, I have still that slight bit of doubt now something is going to let go.
Don`t know what to do?
I know they put these engines in the rangerovers, surely there cooling system must be better than the Vauxhalls as these weigh nearly 3 tons
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Seth on 16 September 2009, 09:29:59
Quote
I`m the same. I just want a good cooling system.
I tow quite a bit and found my temp goes right up on hills then drops when on the flat.
I thought it was ok because it never actually went into the red but after TheBoy advised that the gauges lie, I`m a bit more weary now.
Though it has never been a problem in the past and the car has done a fair few miles towing, I have still that slight bit of doubt now something is going to let go.
Don`t know what to do?
I know they put these engines in the rangerovers, surely there cooling system must be better than the Vauxhalls as these weigh nearly 3 tons
The Range Rovers that were fitted with this engine were also prone to cooling system problems, and the hot-start issues too.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 16 September 2009, 11:41:04
Looks like there`s nothing much that can be done. Might have to strap a truck rad to the front end!!!!!
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 16 September 2009, 19:23:48
As most tractors have been abused by insufficient servicing in their previous lives (4.5k maximum oil change interval), thats a good place to start. Give it a good oil flush using a decent flushing additive.

Also, the rads tend to silt up around 120k, so the rad may need some severe treatment.

Then round it off with a good cooling system flush, using Forte or similar (Holts type products aren't much good at this).

Lastly, if applicable, ensure intercooler fan isn't seized!!
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 16 September 2009, 22:19:55
My intercooler fan is seized!
Would it be better to just ditch this as I can`t really see it actually doing much when it is working.
I might give the rad a good steam clean out.. I`ve given the engine a good flush out, and I change my oil for fun as I get it free from work ;D.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: platty on 17 September 2009, 08:12:06
Quote
My intercooler fan is seized!
Would it be better to just ditch this as I can`t really see it actually doing much when it is working.
I whipped mine out and it was solid. If you can get the circlip off the outside and knock the fan off then you are able to drip some oil down the shaft and leave it to soak over night.
Next day, hold the shaft in a vice and with some oil just keep rocking it back and forth until it is unseized.
Once it spins more freely, then run it across a battery for a while and it will get faster and faster until it is fully operational again.
I have just done this to mine, will hopefully have it back on the car in a week or so and see if there is any difference - or if it ever comes on for a start!
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Omegatoy on 17 September 2009, 08:43:06
the boy was wih me when i ran diagnostic live on the inlet temps with fan off and fan on(mine is wired through a switch on dash for better control) and the difference with it switched on is very noticeable, i.e. try 20degrees difference!!! so when the car is approaching a long hill or something i switch mine on and obviously the ecu detects the cooler incoming air and adds more fuel, the car sails up the hill no probs!! also makes a difference at low revs when has been in trafic etc!!where the i.c. is not being cooled by airspeed through it,
in my book its definetly worth having it !! :y
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 17 September 2009, 09:49:19
That sounds a good idea wiring it into a switch as I have heared people say that they have never known them cut in at all in normal operation.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 17 September 2009, 11:03:18
Quote
That sounds a good idea wiring it into a switch as I have heared people say that they have never known them cut in at all in normal operation.
One of the probs with running viscous is the electric fans don't cut in at slow speed, meaning the intercooler fan doesn't either, resulting in it seizing (poor location)
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 17 September 2009, 12:01:43
so would you remove the viscous or the intercooler fan?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 17 September 2009, 17:46:38
Quote
so would you remove the viscous or the intercooler fan?
Errr, guess what I'd remove ;)
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 17 September 2009, 19:41:30
I don't think I have an intercooler on my car so the 2 fans at the front must be aircon?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Omegatoy on 17 September 2009, 19:53:19
Quote
I don't think I have an intercooler on my car so the 2 fans at the front must be aircon?

Its bolted to the rear of the intercooler, under a rubber shroud that sits between the i.c. and the front bumper! pull the shroud off anf you will see it, but would guess the 99 car would have it, only the very early ones didnt!! :y
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Pitchfork on 17 September 2009, 20:45:41
Quote
Quote
I don't think I have an intercooler on my car so the 2 fans at the front must be aircon?

Its bolted to the rear of the intercooler, under a rubber shroud that sits between the i.c. and the front bumper! pull the shroud off anf you will see it, but would guess the 99 car would have it, only the very early ones didnt!! :y
My 96 one has it because I replaced the seized fan
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: smokingomega on 17 September 2009, 22:08:48
The intercooler is on the drivers side behind the vent on the front bumper. the oil cooler is at the other side
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Pitchfork on 19 September 2009, 16:15:52
Following the Sage advice from TB I have removed my Viscous Fan which was permanently engaged.
Normal running temperature with it on was 92.5, now its 95 (but a lot quieter)
In addition when I stop, the radiator & intercooler fans run on (I did not get that before)
I understand that the 2 radiator fans & the intercooler are switched on by the ECU. My question is: are they on the same circuit or separate ones, because if I was to switch the intercooler on manually (as has been suggested on the forum), if on the same circuit, it would switch on the radiator fans at the same time wouldn't it?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Seth on 19 September 2009, 17:33:35
I'm sure it's possible to connect the intercooler fan so that it runs independently of the rad fans.
Depends on where you 'break into' the wiring loom. Anyone .... ?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Omegatoy on 19 September 2009, 20:21:41
Quote
Following the Sage advice from TB I have removed my Viscous Fan which was permanently engaged.
Normal running temperature with it on was 92.5, now its 95 (but a lot quieter)
In addition when I stop, the radiator & intercooler fans run on (I did not get that before)
I understand that the 2 radiator fans & the intercooler are switched on by the ECU. My question is: are they on the same circuit or separate ones, because if I was to switch the intercooler on manually (as has been suggested on the forum), if on the same circuit, it would switch on the radiator fans at the same time wouldn't it?

not if you run seperate wire as i have to the i.c. fan, TB suggested this may happen if using existing circuits!!!
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 20 September 2009, 21:23:01
Quote
Following the Sage advice from TB I have removed my Viscous Fan which was permanently engaged.
Normal running temperature with it on was 92.5, now its 95 (but a lot quieter)
In addition when I stop, the radiator & intercooler fans run on (I did not get that before)
I understand that the 2 radiator fans & the intercooler are switched on by the ECU. My question is: are they on the same circuit or separate ones, because if I was to switch the intercooler on manually (as has been suggested on the forum), if on the same circuit, it would switch on the radiator fans at the same time wouldn't it?
Not ecu controlled, simply from fan switches in rad.

I remember looking at wiring diagram to manually control i/c fan, and remembering it looked simple enough to do, so just dig out wiring diags (haynes covers wiring for TDs)
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 21 September 2009, 13:37:45
Right then, my next job will be to sort a switch out for the intercooler fan and replace the seized rad fan.

I think I'll be best to replace the rad anyhow as the symptoms are as if the rad just isn't big enough.

Put it this way. Car behaved itself with it being sat at 80'c no matter how hard she was pushed. I go away for 4 months spotting penguins and she first nearly overheats but with a good flush she doesn't overheat but she does run to warm.

As if some of the rad is still blocked?
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Seth on 21 September 2009, 13:51:29
Quote
Right then, my next job will be to sort a switch out for the intercooler fan and replace the seized rad fan.

I think I'll be best to replace the rad anyhow as the symptoms are as if the rad just isn't big enough.

Put it this way. Car behaved itself with it being sat at 80'c no matter how hard she was pushed. I go away for 4 months spotting penguins and she first nearly overheats but with a good flush she doesn't overheat but she does run to warm.

As if some of the rad is still blocked?
When I've got a chance, I'm looking at removing the air-con rad from mine, basically to see if a full flow of air makes any difference. (We never use the air-con anyway!).
Everything else has been done to it, so other than a bigger rad, (which I reckon 2.5TDs really need), I've run out of options with this 'getting too hot' mullarkey!
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Pitchfork on 21 September 2009, 17:56:12
Quote
Right then, my next job will be to sort a switch out for the intercooler fan and replace the seized rad fan.

I think I'll be best to replace the rad anyhow as the symptoms are as if the rad just isn't big enough.

Put it this way. Car behaved itself with it being sat at 80'c no matter how hard she was pushed. I go away for 4 months spotting penguins and she first nearly overheats but with a good flush she doesn't overheat but she does run to warm.

As if some of the rad is still blocked?
What size brush did you use & what colour were the spots?
Assume you used gloss paint given that Penguins tend to get a bit wet & Emulsion would not last ;)
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: chartz on 22 September 2009, 14:05:42
Hi,

The intercooler fan and the aircon fans all work together, there's nothing you can do about it!

About the aircon radiator, it can be really badly obstructed with all sorts of bugs you know, but anyway it's always seemed absurd to me that a radiator could be in front of another one...

As for  the b****y viscous fan clutch, I now think you can't really do without. I've seen my temp gauge reach more than 100°C without it, really frightening isn't it, but it never passes the 92.5 limit with it.
But then I live in France, and I spend some of my summer holiday in the deep south!

I'm on my fourth defective new viscous: I have to run it at 3000 rpm for a few seconds to disengage it every day. But it does remain silent for the rest of the day!
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 13 October 2009, 07:50:21
New rad ordered (£191 inc VAT!  :o) so we'll see if that makes a difference or not.
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: TheBoy on 13 October 2009, 20:30:33
Quote
Hi,

The intercooler fan and the aircon fans all work together, there's nothing you can do about it!

About the aircon radiator, it can be really badly obstructed with all sorts of bugs you know, but anyway it's always seemed absurd to me that a radiator could be in front of another one...

As for  the be ****y viscous fan clutch, I now think you can't really do without. I've seen my temp gauge reach more than 100°C without it, really frightening isn't it, but it never passes the 92.5 limit with it.
But then I live in France, and I spend some of my summer holiday in the deep south!

I'm on my fourth defective new viscous: I have to run it at 3000 rpm for a few seconds to disengage it every day. But it does remain silent for the rest of the day!
easily modified ;D
Title: Re: 2.5TD (BMW Engine) Fan switch location
Post by: Spearmint on 14 October 2009, 13:50:38
'New' rad turned up from a company called 'Applied Radiators' and they are taking it back as well as it's turned up with a few too many dinks on it with two large fresh cuts in the bottom and top sections.  >:(