Missing fan

[mjb]

I've just noticed today that only one of my fans is working! I've tested all the engine bay fuses and they're fine. Does anyone know:

1) Where the connector for the fans lives
2) Where the fan relays live

Number 1 is more important at this stage, as I intend to just shove 12v down it and see if it's the fan itself that's shot

If it is, is there any way of replacing the fans without faffing around taking the radiator out?

[Harshan]

few questions to clarify..
1. does this fan rotates slowly or rapidly
2. when you looking at the fan assembly from front which side fan isn't working. it should be left one.

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one thing to keep in mind that is both fans should hv the connectivity to run at lower speed because in lower speed fans run in serial mode. and most of the time its impossible to run a single fan in lower speed.

if a single fan works in high speed then the reasons might be
-------
1. relay for the fan (check the center cover between two fans) not working
2. 50 amp fuse for the fan blown

[mjb]

few questions to clarify..
1. does this fan rotates slowly or rapidly
2. when you looking at the fan assembly from front which side fan isn't working. it should be left one.

The one on the right (ie. closest to the battery) ain't spinning at all. I have no idea if the one on the left is running slowly or quickly in relation to other 406s as it only spins at one speed, but it does chuck a heck of a lot of air through the radiator.

one thing to keep in mind that is both fans should hv the connectivity to run at lower speed because in lower speed fans run in serial mode. and most of the time its impossible to run a single fan in lower speed.

Ahh I thought the slow fans business was a D9-only thing... That would explain stuff! I've just got 'off' and 'bloody racket' (accompanied by a hefty drop in revs while it spins up) which kicks in at 95c or intermittently earlier with a/c o. Guess it's never worked on mine then

if a single fan works in high speed then the reasons might be
1. relay for the fan (check the center cover between two fans) not working
2. 50 amp fuse for the fan blown

[/quote]

The fuses are fine, that's why I asked about the location of the relays. What centre cover? You mean the slam panel? Any idea how it comes off? If memory serves it looks like it's held on by a pair of plastic studs or something?

[jameslxdt]

is the other fan working at full speed?
99.9% of the time its the fan itself, though there is a set of modified relays that are needed when you replace the fan, ive had this problem on both my saloon '6s

[mjb]

The other fan's either off or on. It's only ever spun at one speed so I can't say if it's fast or slow, but it is bloody loud... Interestingly enough the fuse for the broken fan is a different brand. Looks like the previous owner saw the problem and just tried the easy fix before giving up on it. The fuses are definitely OK though.

According to Haynes the only way to get at the fans is to take the radiator out. Please tell me this isn't so :/

[jameslxdt]

it can be done without removing the rad but you have to be very careful and your hands will be cut to shreds, remove the badge grill, slam panel, you can then CAREFULLY push the rad/intercooler/condenser towards the engine and pull the fan shroud away from it (there maybe some nuts/screws securing it), i know how little room you get on the turbo, try doing this on a 1.9td, there are 3 10 mm nuts holding the fans to the shroud, you need a small 3/8" ratchet and an intermediate length socket, you can squeeze your hand in the gap and undo the nuts and take the fan(s) out, the relays are in the centre between the two fans at the top, the cover for them just pulls off

[mjb]

I think I'll leave this job for a while ;)

[Harshan]

hi mjb.. for me most probably the fan .. it can't be relays if the fan comes at 95 and in 95 normally it comes in low speed.. in my 1.8 petrol the relay box is right behind the front shell. there are 4 knobs to remove and three securing clips 'n then you can take the shell out.. then you can see two fans and fan blades. make sure they're not running 'n the ignition switch off. in between the two fans and on top of the fan guard cover you'll find the relay box kinda trapezoid shape and there are 2 screws which holds the box cover. once you remove that you'll find 3 relays. one bottom and 2 on top in a row. bottom one is the relay which operates both fans at once. right one is the bypass relay which passes current to the bottom relay in the off mode. and when needed to engage in high speed, both top relays engages and this will cut the current to the bottom relay and then the serial mode goes off and each gets full current and both fans start spinning rapidly. better to check these three relays.

[mjb]

in my 1.8 petrol the relay box is right behind the front shell. there are 4 knobs to remove

Those black plastic studs? How do you remove them? I couldn't figure it out...

If the relays are accessible without major surgery then I'll yank 'em out and test them by hand

[steve_earwig]

D'oh! Another thread ended with no result. Did you suss it mjb?

I'm just going to chip in here my own findings because I had a real fight with mine, maybe it'll help someone.

The three relays are really good at catching all the sh!t that's going so the terminals get rather corroded (mine did and they don't even salt the roads here). Unfortunatly you can only get to the fan connections once you've taken the fans off

To get the grill off, those four clips need their centres carfully pulling up & removing (a bit hard for fingernails, maybe a couple of small screwdrivers), then gently lever the top of the grill up around the clips just enough to give you enough to get your digits round them. To get the grill off there's a clip behind the lion, you need to push it straight down with a long screwdriver while pulling the shroud forward of the car, it should be quite easy so don't force it.

Those fans, that has to be the most annoying of designs going, you have to take so much apart to get to the bluddy things! However, if you undo the clips holding the radiator/condensor/shroud behind the slam panel then you get just about enough clearance to get to the 10mm nuts holding the fans on. Use a 10mm socket on a 3/8 ratchet and tape the fecker on so it doesn't keep falling off all the time!! I also took the middle section out of the slam panel but I don't think it helped much (& while I wasn't looking one of the cables for the bonnet release fell off too but that's another story). This took me about an hour or so to get one fan off and my hands really were a state afterwards.

The screws holding the fans onto the motor are LEFT HAND THREAD The motors themselves are held together by staked tabs around the outside where the flange is, you'll need to stick one in the vice and carefully tap them back with a small cold chisel or similar, you'll also need to (gently) force the two halves apart with something like a thin bladed screwdriver. Once it's in two bits you can tip all the sh!t that's inside out and have a look at the brushes.

If you're lucky it's just all the brush dust & rubbish inside that's been stopping them, if not then you'll have to change the brushes or get one that works from the breakers. New ones were about £80 last time I enquired. I got my brother to bring me a 2nd had one from GB in his luggage - probably wouldn't get away with it now. When it got here we realised mine were different - my car has hot weather fans. We also managed to mangle the shaft trying to fit it and we ended up just using the brushes (which we had to file down). 2 years later it still works though. Don't bother staking the casings back together, clean up the joint and use epoxy resin. It'll make it easier to take apart again... Once it's in one piece again give it a test, mind you put your foot on it or something as it'll try to jump out of your hands!

While you have your vice handy, stick the motor in it and chisel/drill/butcher those studs off so you've just got holes. Buy half a dozen or more (you're bound to drop some!) 10mm nuts and bolts (mine were about 20mm long but the longer the better, within reason) and, with that tube of epoxy, glue the bolts behind the shroud so you have threads sticking out to mount the fan motors on. It's fiddly and you will end up with the epoxy on your fingers, just try to keep it off the threads. I used stiff thin wire to pull the bolts into the holes from behind and applied the epoxy as late as possible. Once it's dry you just need to offer up the fan motors onto the these bolts and just stick the nuts on (preferably with washers). Not too tight or you'll upset the epoxy.

Now see if it works. Good luck!

[mjb]

Been wanting to have a crack at it for a while, but the weather's been a huge limiting factor I'll definitely be using your reply to help though - thanks

[Nandad]

Magic information. Damm right about multiple lacerations. Useful trick strap forearm with gaffer tape. And use an old broomstick to hold down cowl away from radiator and a gopher to put pressure on it.
Check bonnet release BEFORE replacing top scuttle. Saves hours of fun.