General 1998 Ductato - why 2 fans?

[Matt49]

Hi, I run a 1998 2.8 no turbo LWB. The engine has been running a bit hot for some time and today I replaced the radiator.

I'm confused about this vehicle having twin fans. The smaller one of the two kicks in and out when the gauge needle is vertical. The bigger fan doesn't seem to run at all.

How should the bigger fan work - same time as the smaller one? at a different temp?

Overall the engine seems to run hotter than it did up to 2 years ago (had the van 8 years) and I've got a feeling, the bigger fan not working is the reason.

any pointers at all on why 2 fans and when should they both work?

Thanks

 

[mikey72]

Hi,
I could be wrong, but I understood that the fans on some models worked at different temperatures.
And they fail as well.
It's very common for the older vans to start to run warmer, usually a new radiator and a good flush sorts it out, but it's worth replacing the switch for the fans at the same time.
Mine (1.9td motorhome) has started running hotter in recent years, usually when I put my foot down, I have wired a switch on the dash to turn on both fans by hand, until I replace the rad.
Google "Ducato overheating" and similar, there's all sorts of responses and tips.

 

[Matt49]

mines definately running hotter than it did for the first few years. I thought this was down to the rad getting on a bit. Now the rads been replaced, it runs slightly cooler but still hotter than earlier and the fan cuts in much earlier. does the main fan that isnt working on mine have a seperate relay or fuse does anyone know?

 

[Fistral fig]

I have a 1988 model with 2 fans, and wondered whether either worked or not, to check if they were working left it running for a while and one fan was kicking in and out but I too wondered about the second one, I left it a lot longer and it still didnt come on, so I clamped the top hose shut with a clamp and waited gingerly, eventually the other fan kicked in, so it has a 2 stage switch, and mine has seperate relays and fuses for each fan, hope that is of some help.FF

 

[MYTHING]

Hi

I have a 51 plate 2.8 non turbo and have replace the heater matrix (guide available under MYTHING) and main radiator, the two fans are made to come in at different temperatures, on the back of the fan mounting is a black box about 5" square, undo the four small screws and you will find two relays, because my fan had been running almost constantly one had burnt out (easy to find it was black and melted!) I have now replaced that relay and now both my fans run as they should.

If you look at the nearside of the radiator you will find two temperature switches at the bottom, they are for the fans.

Regards

MYTHING