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Discussion Starter #1
Hello,
Haven't located an answer to these questions when searching the threads, so here goes.
Firstly, it's a T4 2003 V6 auto gearbox we're talking about.
My two radiator fans have shattered and vibrate the front end a bit too violently for my liking when they engage.

Q1- do they vibrate because the outer circle is broken or is there a bearing/balancing issue to consider (all blades are intact, just that outer ring missing pieces)?

So, Im about 150km from my home mechanic. I'd very much like to disconnect the fuse for the fans and drive (highway drive) home. However, according to the fuse card, that fuse caters for the "engine coolant blower motor control module, engine coolant pump motor.
Now I didn't know I had an engine coolant pump. So then

Q2 Do I risk damaging the engine if I drive with that pump fuse disconnected?

It is summer, and unusually warm, but I can wait until nightfall to get a cooler highway drive.
Any thoughts or ideas?
In addition to that - how hard is it to replace those fans? I saw another user ask that question 5 years back and receive no answer.
Thanks in advance,
Slick
 

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The fans rotate at high speed...the smallest amount of imbalance will cause vibration (and bearing wear).

If you have aircon, do NOT use it....it NEEDS those fans running.

Engine coolant pump is a water pump that runs on AFTER the engine is stopped....to prevent "hot-spots" in the system.
LOADS of people never knew they had one, and almost as many later found the pump was seized!
In MY opinion, you can drive, keep an eye on temp gauge (back off a little if it rises over mid), and AFTER your journey, leave the engine to idle for 5-10 mins to allow the water to circulate.
Avoid (as if you can) as many mountain passes as possible, even taking a few extra km on "level" roads will help. (Or drive as slow as possible up the hills.)
If/when you need to take a ferry, try to get there early, and again let the engine idle for a few mins.
Not the time of year to want this, but putting the interior heating/fans on high will help (Praise Odin for windows!)

OK, it's finally "summer" in Norway, but not exactly the tropics,

A little insight, many years ago I knew some "people" who ran an inport/warehouse for electronic goods (UK CB Boom) and each made a fortune.
2 of the guys bought "performance" cars (Lambo, etc) b ut the 3rd just bought a Porsche.
HE used to laugh at them, as arriving at work, they had to sit in the carpark, engines idling, to cool down.
He went inside and drank his coffee!!!

I would say, 150km, taking it careful, should NOT be a problem....just watch that temp gauge!
 

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Lol Odin :ROFLMAO:

To answer the question about swapping the fans, its easy peasy & they have to be removed to replace your radiator core. They come out with the plastic shroud surrounding them. 8 screws if I remember rightly. The bottom 3 will likely be rusty though.
 

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Discussion Starter #4
I'm very much obliged for those quick responses!
Gaz: the 150kms are reasonably gentle (for Norway), no ferries. Not the tropics, but the heat is lingering and is pretty much as hot as gets around here.
Bingley: I actually had the shroud out today (6 bolts, 1 previously rusted/snapped, managed to lose another).
If these fans are as finely balanced as Gaz suggests, should I be looking to replace the entire unit (motor+fans), or begin with fans only and work on from there?
Background story to this situation: I changed the spark plugs yesterday. After finishing, van ran perfectly. Took a long drive to test it and after about 25 kms it began vibrating ...engine light came on. I figured something came loose (that I was quite disappointed at the time is an understatement). Against my better judgement I went further, pulled over and did some shopping, and in the carpark 40 minutes later, restarting the motor and turning on the AC, a great shuddering and then fan damage. It seems one of the clips to the plug lead didn't secure all the way. After rechecking the leads this morning and resetting the engine light, drives smooth without issue. Except the fans now (sigh). But, is it possible the rough running could have caused the imbalance of the running fans?
I'm trying to understand how/why these fans shattered.
Thanks again.
Slick
 

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This is a rare problem. I don't think I've seen it mentioned before. This means a second hand shroud with fans should be a reliable fix. I suspect they must of been damaged physically by an unknown object. I've got a spare set it's just a shame you are so far away from me.
 

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Just thought of another wild possibility. The fan bearing may of collapsed? Causing the blades to catch the shroud/Radiator core?
 

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Discussion Starter #7
That's an interesting thought to consider.
When I had the radiator tilted for 2 hours when changing the plugs perhaps something else gave (bearings?), but it seems unlikely. I drove a while with that rough motor before the fans shattered, so perhaps they simply couldn't take the imbalance.
But I'm still not convinced. I should mention the van has LPG installed, and the gas lines feed into the jets between the fans and the block. My own guess is that the already tight space in there was somehow disturbed by my plug change and perhaps those lines caused the obstruction, but a rudimentary check didn't show any damage or signs of impact on the gas lines. Still, that seems the more likely reason, scary as it seems.
With the outer circle rim only damaged on both fans (no blades) the source of impact/shatter still a mystery.
The shroud seems fine to me, no cracks or anything visibly amiss. Is there another reason I should be considering changing this? I ordered a pair of fans that I hope will be simple enough to install and then - fingers crossed - the whole system runs smooth again. I'll keep this thread posted when the job is done.
Incidentally, the 150km drive went very smooth, thanks again for the advice. It was a midnight run, cool night, so managed to drive the whole way with windows half open and heater full power.....surprisingly pleasant. Not a single obstruction or traffic light from departure to parking (kept her at 2800 rpm/90 km/h all the way), and sat 10 minutes on idle with heaters running at destination. Hopefully no problems.
Cheers again,
Slick
 

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Discussion Starter #8
So, just to add a happy ending to this thread - and for the benefit of anyone else in a similar predicament, the case is closed.
I replaced the fans with a couple I'd found on autodoc. 45 pounds all up for both delivered to Oslo. I took another good look around the motor when the shroud was out. I still can't figure out what the fans hit to shatter. There were a few impact spots on the radiator, probably from the pieces that went flying about post-shatter, but nothing substantial. I notice the LPG installer had to cut some grooves into the shroud frame to accommodate the LPG lines (that's how tight it is in there).
Again, I can only conclude I'd moved a line slightly and the vibrating due to rough misfiring caused the obstacle for the fans. Nothing else makes sense (and I know I didn't leave a tool in there - another good theory).
The fans were a simple swap job and everything purring hunky dory now, much to my relief.
Thanks again for all the help and feedback.
Slick
 

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I notice the LPG installer had to cut some grooves into the shroud frame to accommodate the LPG lines (that's how tight it is in there).
I think there's your answer. The fins on the fan twist in operation to allow more air flow. When fully extended they almost touch the shroud. Hopefully you double check the LPG lines don't interfere with your new fans when extended or it will happen again.
 

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Discussion Starter #10
Thanks for that. I've placed strips on these lines in a bid to keep them from wandering, hopefully that will do the trick. The driving so far has gone well, although admittedly when the fans engage I feel and hear a droning hum. Could be the new type of fans replacing the old, or my imagination, but never used to even notice when those fans engaged previously.
 

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Thanks for that. I've placed strips on these lines in a bid to keep them from wandering, hopefully that will do the trick. The driving so far has gone well, although admittedly when the fans engage I feel and hear a droning hum. Could be the new type of fans replacing the old, or my imagination, but never used to even notice when those fans engaged previously.
They may break again if the gas lines are not moved from the shroud area. The angle of the fan blades increase as the radiator gets hotter. The mechanism works like a thermostat. You shouldn't hear any noise above the engine sound unless the van isn't moving in traffic & you have the windows down. The guy who fitted your lpg may know gas but doesn't know these vans. I'd personally kick him in the ass. :LOL:
 
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