Might be a stupid question but just wondering what the loud fan noise is that goes on for a couple of minutes after the engine has started and it does it no matter if the engine is hot or cold. It sounds a bit like a really loud US army jeep when setting off after the engine has been switched off for a while. Maybe other makes do it too but I’ve only ever driven volvos.
dave75:
Might be a stupid question but just wondering what the loud fan noise is that goes on for a couple of minutes after the engine has started and it does it no matter if the engine is hot or cold. It sounds a bit like a really loud US army jeep when setting off after the engine has been switched off for a while. Maybe other makes do it too but I’ve only ever driven volvos.
Only thing I can think of is ours run at higher engine revs when cold to warm up so the adblue can work.
its the viscos fan running up, stops when it goes in freewheel after a couple of minutes, then cuts in and out as required 
I’m in a Renault and it does the same.
Maybe it’s a similar engine?
That’s because it’s a Volvo with a Renault cab on it. Same engine, same gearbox, same chassis.
206doorman:
I’m in a Renault and it does the same.Maybe it’s a similar engine?
Renault has got a volvo engine. No idea why it does that. I know its the engine fan but why it needs to do it while the engine still cold I dont know.
damoq:
206doorman:
I’m in a Renault and it does the same.Maybe it’s a similar engine?
Renault has got a volvo engine. No idea why it does that. I know its the engine fan but why it needs to do it while the engine still cold I dont know.
the idea is to get the engine up to running temp faster
Moose:
damoq:
206doorman:
I’m in a Renault and it does the same.Maybe it’s a similar engine?
Renault has got a volvo engine. No idea why it does that. I know its the engine fan but why it needs to do it while the engine still cold I dont know.
the idea is to get the engine up to running temp faster
But how can it get up to temp faster if the cooling fan is on. 
damoq:
Moose:
damoq:
206doorman:
I’m in a Renault and it does the same.Maybe it’s a similar engine?
Renault has got a volvo engine. No idea why it does that. I know its the engine fan but why it needs to do it while the engine still cold I dont know.
the idea is to get the engine up to running temp faster
But how can it get up to temp faster if the cooling fan is on.
as the thermostat wont be open below running temp the coolant wont be going through the radiator in any great amount so the fan wont be cooling owt anyway!!!
the idea is the extra effort to spin the fan at full speed is what will warm the engine faster!!
hope this helps
moose
Every modern truck on earth does it, it’s just the fan cutting in and it does it qute often when running, you just don’t notice it.
I can’t believe some of the questons I see on here 
Cheers for the sensible answers, thought I’d get slated. I’ve been on a new motor with I-shift for the last few weeks and noticed it more than with the last motor which had a manual box so thought it might be something to do with that- until I saw an old knackered volvo coming off a ferry making the same noise. I started wondering what it was after taking a 15 min break after 3 hours of driving so didn’t think the engine had cooled enough to warrant the use of the fan.
Pat Hasler:
Every modern truck on earth does it, it’s just the fan cutting in and it does it qute often when running, you just don’t notice it.I can’t believe some of the questons I see on here
I didn’t know what it was so I asked, no shame in that.
Don’t let 'em get to you bud! 
I thought that a viscous fan works the opposite way around.
When cold the fluid is liquid and sends no drive to the fan, when hot the viscous fluid hardens up and sends the drive to the fan.
cerainly on Mercs you can hear the fan cut in when the engine gets hot.
I don’t see any point in having a drive to the fan when the engine is cold as this will only increase (fractionally) fuel consumption and todays engines do everything possible to avoid this.
No idea what else it could be though
Moose:
damoq:
Moose:
damoq:
206doorman:
I’m in a Renault and it does the same.Maybe it’s a similar engine?
Renault has got a volvo engine. No idea why it does that. I know its the engine fan but why it needs to do it while the engine still cold I dont know.
the idea is to get the engine up to running temp faster
But how can it get up to temp faster if the cooling fan is on.
as the thermostat wont be open below running temp the coolant wont be going through the radiator in any great amount so the fan wont be cooling owt anyway!!!
the idea is the extra effort to spin the fan at full speed is what will warm the engine faster!!
hope this helps
moose
You learn something new every day. Thanks. 
dave75:
Cheers for the sensible answers, thought I’d get slated. I’ve been on a new motor with I-shift for the last few weeks and noticed it more than with the last motor which had a manual box so thought it might be something to do with that- until I saw an old knackered volvo coming off a ferry making the same noise. I started wondering what it was after taking a 15 min break after 3 hours of driving so didn’t think the engine had cooled enough to warrant the use of the fan.Pat Hasler:
Every modern truck on earth does it, it’s just the fan cutting in and it does it qute often when running, you just don’t notice it.I can’t believe some of the questons I see on here
I didn’t know what it was so I asked, no shame in that.
Exactly. Does anybody know if the Kerax now uses a Volvo engine?
del949:
I thought that a viscous fan works the opposite way around.
When cold the fluid is liquid and sends no drive to the fan, when hot the viscous fluid hardens up and sends the drive to the fan.
cerainly on Mercs you can hear the fan cut in when the engine gets hot.
I don’t see any point in having a drive to the fan when the engine is cold as this will only increase (fractionally) fuel consumption and todays engines do everything possible to avoid this.
No idea what else it could be though
you can also hear volvo fans cut in and out when the engine gets hotter!, you may well be right about the fuel consumption as it takes a fair bit of power to spin the fan at full speed, but volvo have never been the best on fuel economy!
i have only ever ran volvo’s myself and know more about them than say daf,merc,iveco etc
just another point some operators in this area are finding the fuel returns better on renault trucks with the volvo engine than the fh/fm the volvo engine was intended for in the first place!!!
Happydaze:
dave75:
Cheers for the sensible answers, thought I’d get slated. I’ve been on a new motor with I-shift for the last few weeks and noticed it more than with the last motor which had a manual box so thought it might be something to do with that- until I saw an old knackered volvo coming off a ferry making the same noise. I started wondering what it was after taking a 15 min break after 3 hours of driving so didn’t think the engine had cooled enough to warrant the use of the fan.Pat Hasler:
Every modern truck on earth does it, it’s just the fan cutting in and it does it qute often when running, you just don’t notice it.I can’t believe some of the questons I see on here
I didn’t know what it was so I asked, no shame in that.
Exactly. Does anybody know if the Kerax now uses a Volvo engine?
I think the 11 litre is a Renault lump, 13 litre Volvo unit.
starfighter:
Happydaze:
dave75:
Cheers for the sensible answers, thought I’d get slated. I’ve been on a new motor with I-shift for the last few weeks and noticed it more than with the last motor which had a manual box so thought it might be something to do with that- until I saw an old knackered volvo coming off a ferry making the same noise. I started wondering what it was after taking a 15 min break after 3 hours of driving so didn’t think the engine had cooled enough to warrant the use of the fan.Pat Hasler:
Every modern truck on earth does it, it’s just the fan cutting in and it does it qute often when running, you just don’t notice it.I can’t believe some of the questons I see on here
I didn’t know what it was so I asked, no shame in that.
Exactly. Does anybody know if the Kerax now uses a Volvo engine?
I think the 11 litre is a Renault lump, 13 litre Volvo unit.
the 11 litre is also a volvo unit
Is that the one that started out as a Volvo 9 and got bored out and fettled by Renault and proved surprisingly good, and was then adopted by Volvo too? Or are there two 11 litre engines?
Cheers chaps 