Fan blade bent and catching radiator

[FEP]

I fitted a new genuine fan about 4 years ago on my M20 325i.

Opened the bonnet today to investigate a rattle on start up and found that one fan blade had broken off and the one next to it was twisted and bent forward at the tip and beginning to cut a groove in the radiator fins.

Any ideas as to what has gone on here?

The water pump is fairly new and the bearing on it is good without any play. The rad is also reasonably new - aftermarket item and it is firmly secured and doesn't move around.

The other fan blades have at least 5mm clearance from the rad.

Thoughts?

FEP

[e30topless]

Hows your engine mounts ?

[FEP]

I reckon they're OK but good thought. I'll give the engine a good push to see what the fore and aft movement is like.

[aimlessrock]

check the fan is bolted onto the viscous coupling the correct way round.

[FEP]

check the fan is bolted onto the viscous coupling the correct way round.

It is!

I'd have much bigger problems if it was on the wrong way.

[xavier]

I had the same issue a few months back. I checked all the mounts for the engine and gear box. they were all good. I changed the fan and the issue was resolved. I never found the cause. My fan was very old though. I think it may just have been the plastic going brittle due to heat and age. A did spend a bit of time when I put it all back together making sure the radiator had plenty of distance between the itself and the new fan.

[FEP]

I had the same issue a few months back. I checked all the mounts for the engine and gear box. they were all good. I changed the fan and the issue was resolved. I never found the cause. My fan was very old though. I think it may just have been the plastic going brittle due to heat and age. A did spend a bit of time when I put it all back together making sure the radiator had plenty of distance between the itself and the new fan.

Thanks for that xavier. How did you adjust the distance between fan and rad? Doesn't seem to be any scope for adjustment.

[daimlerman]

I would 'think' that the fan ageing is the root cause of your problem.

Assuming that the engine is not throwing it's self around,of course!
I fitted a pair of engine mounts from Burton,the Ford tuning place,a while back...I have no engine movement issues.

[FEP]

I would 'think' that the fan ageing is the root cause of your problem.

Assuming that the engine is not throwing it's self around,of course!
I fitted a pair of engine mounts from Burton,the Ford tuning place,a while back...I have no engine movement issues.

Ageing? It's only 4 years old Malc.

[xavier]

My car had a knackered Air con system, with the air con radiator in front of the engine radiator. When I replaced the fan I took both the radiators out. I threw the Air con one in the bin. I think with this out I managed to get the drivers (RHS) top mounting point back a bit. I will take a look at the weekend. Cant remember exactly what I did with the mounting point.

[daimlerman]

I would 'think' that the fan ageing is the root cause of your problem.

Assuming that the engine is not throwing it's self around,of course!
I fitted a pair of engine mounts from Burton,the Ford tuning place,a while back...I have no engine movement issues.

Ageing? It's only 4 years old Malc.

4 years old or 24 years old,your fan is buggered,it's lost one blade and bent another!

So why?
Fan can only belt the radiator if the engine moves forward or the radiator moves back,or if the waterpump bearing is buggered,or if the fan is not fixed properly.
Which is your problem?

[FEP]

I would 'think' that the fan ageing is the root cause of your problem.

Assuming that the engine is not throwing it's self around,of course!
I fitted a pair of engine mounts from Burton,the Ford tuning place,a while back...I have no engine movement issues.

Ageing? It's only 4 years old Malc.

4 years old or 24 years old,your fan is buggered,it's lost one blade and bent another!

So why?
Fan can only belt the radiator if the engine moves forward or the radiator moves back,or if the waterpump bearing is buggered,or if the fan is not fixed properly.
Which is your problem?

Well I must admit, I'm beginning to think that one blade broke off just because these things can happen, and in doing so, it bent the next blade enough for it to catch the rad.