How dirty did diesel fan discs/blades get in service?

[Dr Al]

Hi,

I think the topic title says it all - playing with some weathering and wondering if the red fan disc on some diesels should be toned down at all - my instinct says no as presumably most roof muck (i.e. primarily exhaust is lifted clear of this area in running). Any thoughts from the weathering experts out there?

Cheers,
Alan

[Mr PJ]

I tend to agree with what you say Dr Al. One problem is that there are not many clear photos of locomotives fans grills to get an idea of how weathered they become.

One memory I have from about 30 years ago is of a 47 at Harwich Parkestone Quay - which I was watching from the overbridge - was just how comparatively clean the fan-blades were as they slowly rotated. And this was a rather grubby freight loco! My feeling is that the red should still be visible, and maybe just a subtle wash of dark grey etc.
Regards,
Paul

[Chris]

! No longer available

Skip to 32 mins 20 secs (unless you want to wach half an hour of diesel action!) 

[MJKERR]

I would agree, very light weathering as the fan would only be affected by either long term dirt build up or extreme oil contamination

I used to stand on the overbridge at Aberdeen station sometimes to look at the fans of locos as they went underneath
It was rare to see a very dirty one, but equally rare to see one completely clean

However, I can remember one that was BLACK and coated in oil, as was the side of the loco (which I am ironically modelling)

[Mr PJ]

Ha, ha - the fan on the 37 in the video is extremely well-worn with paint etc flaking! I do remember back in BR days though the radiator fans would get attention with a lick of paint every few years or so being easily accessible, so it was probably rare to see them in this poorer condition.

I'm not sure with 47's (with the exception of 47401-420) which unusually had hydraulic driven fans whether the hydraulic oil - which was under considerable pressure - might occasionally spray upwards and contaminate the fan blades, but could well be possible.

Cheers,
Paul

[acko22]

Dr AL,

From what I have seen of them up close they tend to fade a bit going outwards due to the friction with the air but as for grime they dont seem to get that bad as a whole although the centre can get a bit mucky.

[DELETED]

If it helps here's a screen grab as I was interested myself.  I've fitted some pretty big industrial fans and they always collect surprising amounts of muck by virtue of the airflow -always amazed how much dust / things like dandelion seeds manage to stick to the trailing edge in my cases.  We used to clean blades at least once a week if not twice and they were blades behind filters. Maybe not when it comes to locomotives?...

[Dr Al]

Just a quick one to say thanks to all those who responded - it seems safe to assume they will stay fairly clean and fade to a similar level as the rest of the loco 

Thanks all,
Alan